@knunne1 Thanks for that great comment, I'm actually looking into going back to Airtex to do some more of these videos so that is one request I hope to fill.
Very detailed explanation. I’m sure there are a people who are interested to learn all about electric fuel pumps. It’s hard to look for videos like these so thank you for uploading it and satisfying people’s curiosities.
@brian5446 Either that or you can just cycle the key before you crank the engine when you go to start the car, I did that for years on a car that I used to have as the pump still worked fine.
@TheTexasCoder That is very true, I like to get my info from the source whenever I can and this guy is about as close to the source as you can get from what I've seen. Thanks for the comment.
This video defiantly confirms that I have a fuel injector problem with my truck and not a fuel pump check valve problem because of the bleed off time that my fuel pressure gauge was showing. When I tested my truck the pressure bled off immediately after shutting the truck off.I'm looking at getting new injectors and I know now its not the pump.Great video Eric and thanks for all the info.
Great video. It was nice to see the actual disassembled pump and to hear about the check valve, as that is something I needs attention on one of my vehicles.
@alundrasrt No need to worry about that as the pump is submerged in the gas in the tank which is what 'lubricates' (if you could call it that) and cools the assembly, priming it is not necessary at least with the pumps I've installed.
Eric this video has come in handy. I'm in the middle of a GM fuel pressure diagnosis and just how he explained the check valve and everything else has given me such a better understanding of the pump. Thanks and I'm literally still dirty...
Thanks to Airtex and ETCG for a great video. I am amazed at how, what is basically plastic and a motor can deliver combustible fluid so reliably. Hats off to Airtex's Engineering & Production's teams and their quality! I am guilty of not recognizing how hard and trouble free fuel pumps work. I enjoyed seeing how the Car's trouble symptoms related to the components in the pump and the various versions made as well as how they are tested. Again Great Video, more please!
@Begbucks Yes they did have a very extensive diesel section at the facility, I didn't spend a whole lot of time there on this trip, perhaps the next if I get the opportunity.
@MrOne2watch It does sound like a possible check valve issue but use a fuel pressure gauge to confirm it. As for Airtex pumps I've never had a problem with them. I don't have a video on that particular replacement at this time sorry.
@Bushougoma No, in fact the fuel flows right through the pump. Remember in order for combustion to take place you need O2 and if the pump is full of fluid there is no O2 for combustion to occur.
This guy is such an engineer. When he's talking to Eric he's looking at the disassembled fuel pump while answering the question and not even looking anywhere near Eric. The machines interest him more.
@tinydx95t2 I wouldn't condemn an injector right off if you don't have a problem with the way the engine runs, normally if an injector is that bad you will have a very wet spark plug and a misfire on the effected cylinder. You might want to try your test with the return line pinched off as it could be a fuel psi regulator problem. Good luck.
awesome video. I have been trying to find out why my 02 jeep wont start on the first try. people kept telling me its the fuel regulator that has the check valves. even the dealer couldnt tell me for sure, they just tell me to change everything 650.00! I will buy the airtex pump assy and put it in. Thanks for the great video Eric!
@paul06660 If it's the original pump it's not likely that it's bad, in fact OE Honda pumps hardly ever go bad. You say the pressure is 40psi, but have you checked it during the extended crank? If not you might as the pump may be good but the check valve may be stuck not keeping pressure on the system after shut off. Lastly I HATE aftermarket distributors as I've seen nothing but problems with them, you may want to check your timing.
@lol123321123321 That sounds like a check valve issue. Normally when pumps go bad they just don't run and cause a condition of no fuel pressure. I actually have another video with Airtex covering that procedure, How To Diagnose A Fuel Pump Failure.
Great video! Thank you AirTex and EricTheCarGuy...I love technical shows like this. Eric, all I have to say, after watching Curt's reactions to your questions, that man has FORGOTTEN MORE ABOUT FUEL PUMPS then you and I will ever learn :-)
Goodness, that's extremely complex! Its amazing these things don't fail more often. I've never owned a car that had a fuel pump fail until recently my 92 Astro van fuel pump started working intermittently. Kick the gas tank once or twice and it works again. Finally decided to change it. See this is why people want electric cars. wayyyyyyy fewer parts to fail lol.
I find it fascinating and a little counterintuitive that the brushes are submerged in gasoline with the rest of the pump. The brushes on most motors show visible spark, and those brushes on the fuel pump look smaller but similar. The only thing missing seems to be oxygen, and when the tank runs dry there will be air in the tank, too. Am I missing something?
Great clip,thanks. Is anyone able to answer a question which comes to mind while watching this; the float /level rheostat and the motor brushes and armature setups both appear to have active voltage circuits and (to me) apparent potential for arching or sparking.the fuel even passes THROUGH the motor ! Obviously this is a completely safe feature ,but I can't quite understand how these functions are included IN the actual tank,with no regard for a possible ignition of the fuel? Any explanation would be appreciated. Thanks in advance.
Notes: In many of these fuel pumps, there are a PAIR of one-way check valves. One is to maintain fuel pressure in the downstream fuel lines so as to keep from having long cranking times when you come back in the morning. The other check valve is for pressure relief in case the system is building up too much pressure for normal operation, it just bleeds off through the check valve which is oriented to release the excess pressure just below the normal system operating pressure. However, if a piece of debris gets caught in the rubber "seat" of the check valve, or the rubber of the check valves seat deteriorates over time sufficiently, the fuel pressure will bleed off in a certain amount of time when the vehicle is not in use. When you look at the top of the fuel pump and you see two different electrical connectors, one is of course for the power supply and the instrument cluster gauge, and the other is likely the electrical connect for the vapor sensor for the fuel tank.
Sure would be nice if you guys made a pump that mounted OUTSIDE the fuel tank, perhaps inside a metal cage to protect it. The fuel could still flow-through for cooling. The ability to replace these things is now limited to few diys or an expensive trip to the shop. Airtex guy did a beautiful presentation. Wish I was that good !
Cool video. Not something you usually think might be stopping your car from starting, until you see this and cross reference it with the symptoms your car is having. Luckily mine is still OK, but not fun to replace if yours is in need of repairs. Thanks for teaching me another thing about cars I might need if it stops working. :-)
Thank you so much for sharing Eric! Wow, I believe the pressure relief valve went bad in my factory fuel pump. (2001 Chevy Cavalier 2.2). I hope you don't mind me sharing this but - I have never seen this before or I have not found any information on this type of fuel pump failure. I'm having a no start condition. I have spark everywhere spark should be. Testing the pump; the pump sound was normal, I could hear the pump running just fine. I found very low fuel flow, pressure at the filter, but not much fuel volume, I found it pumped about 1/2 quart in 5 minutes, when it should flow about 1 quart in 30 seconds. I very carefully removed the fuel pump and energized the fuel pump motor, the gas pressure was shooting out of the motor's top housing hole and barely going through the fuel line. I guess I have to replace either the pump or the fuel pump assembly.
Can't be just me, I have had several of these in a suburban, I drip the tank, clean the tank, replaced with a life time warranty Airtex ( I bought it when there was still lifetime warranties on these thank goodness) worked great for about 5 months and poof, gotta get a new one. 1997 suburban, 5 airtex pumps before I sold the truck off. 4 failures in 4 years not counting the last one I sold the truck off with or the first one that was OEM. I didn't have to clean the tank after that 1st time since it was clean as can be. the filters were not clogged, the just quit working. I am currently working in a GMC Yukon and decided to try a AC Delco. I am curious to see if it's works better.
@beefystik well that's what i understand from your comment , we all like the guy and i can tell you i have watched most of his videos maybe excepts the FATR's and i never remember he ever asked this or complained from repeated questions ! On the Contrary !! he always answer comments no matter how silly or lean or repeated they are! he even answers comments after while that makes you think he will never get back to them but he always does ! .
they know alot about pumps for people that can't build one that works. I had one doa. pushed 12psi new out of the box. second one I used lasted 25 miles and broke down on the side of the highway. I laid in gravel and broken glass to replace it with pos Carter pump that cost half as much and lasted 6 months. first two times I just needed to get by a few days, and they didn't even last that long. the Carter pump was the only one I could get same day where I was broke down. BTW, airtek pumps were both all plastic drive mechanisms with thinner teeth then the brass assembly in the OEM Bosch and Carter pump. the airtek that lasted 25 miles was also really loud and pulled nearly 20 amps, the Carter pulled 9.6 amps while actually pumping. even though the airtek couldn't start the car, it did have enough left in it to pump 10 gallons out of my full tank before I smashed it with a rock and left it with the broken glass. this time I'm special ordering a walbro. the first one lasted 28 years and 320k miles, not minutes.
I have a problem with in tank pump I want to use for inline pump. The bottom of pump has a large intake hole. There's also a very small hole in bottom plastic that is pressurized when pump runs. If I plug small hole pump fails and no fuel flow. Small hole open pump works but fuel comes out small hole & normal outlet on top. Obviously can't have fuel spraying all over from small hole. What's happening?
Great video! Very informative. That's why I never try to drive my vehicles passed 1/4 if I can prevent it. Driving towards flat E is the primary reason fuel pumps fail prematurely!
I wonder if We change that "bag" or filter pick up it would help our pumps last longer since it wouldn't have to work so hard as it gets dirty...nice vid man! Im looking for your coolant vid haha
Is there a quality pump (motor) I can swap into my sending unit (airtech doesn't seem to be in business anymore)? Backstory, I really thought OEM would have been great but seems it's not what it used to be. I'm having a HELL of a time with a factory / OEM replacement fuel pump. I swapped out simply cause was old, preventative maintenance. I'm on my second OEM pump in 2 years. I keep going back and forth with the manufacturer that wants me to check various things but I've went through the line set, electrical circuit, regulator, injectors, rail, cannot find any other faults anywhere. Long story short, it's running 7 PSI lower than spec.
If the check valve is bad, then the hot engine starting gets difficult. The fuel pressure is lost quickly and with a hot engine, this results in fuel vapours forming in the fuel lines. This leads to hot engine restart a little longer.
Great video. Is there a way to test a used fuel pump motor to see how strong it is? I guess put it in the tank, do KOEO and KOER pressure tests at the rail then leave it over night to see if the check valve holds the pressure?
I have a 96 F250 w 60,000mi it has dual tanks. I'm experiencing low fuel pressure on both tanks. Front tank @18 psi and rear tank @ 28 psi. Both tanks hold pressure for awhile but not over night. Should I replace both pumps or is there a way to find out which pump is the problem? Great video by the way!
@donbehatin I have. I did a test with a fuel pressure gauge and I performed the test 6 times in a row and 4 out of the 6 times I performed the fuel pressure test the pressure leaked off.Plus I have been changing my oil about once a month because the oil smells like gas. I have great compression so its not rings.and I've looked at the rest of the fuel system and everything is good.The only 2 things that would cause readings like what I got is a faulty check valve or injectors.
@EricTheCarGuy What if you had an empty tank with just vapor in it? Couldn't that be an explosion hazzard if you get a spart or arc from the pump motor?
It helps to have a visual representation like this, and a "plain english" explaination of each component. I can't learn shit from just a bunch of text, a have to at least see a video like this, but I prefer to actually get my hands on it at some point.
Now I see why modern designs incorporate a fuel filter proximal to the pump, to keep debris from clogging the pump turbines. Too bad the new fuel filters are so hard to get to....
good video. last week i destroyed two of this type of motors to know what is there inside mees how it pumps fuel when it submerged in fuel. but you given good description about this motors. thanks.
none of my cars have any of those stupid fuel pump modules. they simply have the fuel pump that he is holding in his hand hanging from the fuel pump sending unit. i dont know why they went to the module setup but they are very expensive to replace, somewhere around 300 bucks. another reason why i like older cars, parts are allot cheaper and things are generally simpler to work on
i have a 2005 Chevy equinox the fuel pump went out does the electrical pump come with the fuel pump also or does it have to even be replaced? or just the fuel pump
"I have a question about fuel pump design. I was wondering why fuel pumps are designed to use the fuel itself as a lubricant and coolant. Why is this so? Most other electric motors I've seen don't need any cooling to operate continuously. Also, since fuel is going through the motor brushes, wouldn't there be a spark there while the electric motor is spinning? Wouldn't that ignite the fuel? I don't know much about these things..." most electric motors have a lubricant inside them, unfortunately gasoline acts as a solvent and washes off the lubricants. So the pumps are designed to use gasoline as a lubricant instead. Many fuel pump motors are quite powerful for their size, and run at 100% duty cycle (the run continuously) and will overheat without a constant flow of cool fuel. Most electric motors that run for extended periods with 100% duty cycle have some form of cooling. also keep in mind some electric motors are air cooled without a fan and may or may not use a heat sink to aid in cooling depending on how much heat they put out. Liquid gasoline and diesel is non flammable. In fact assuming there is no vapors sitting on top of the fuel you can throw a lit match into a bucket of gasoline and it will put out the match. Gasoline VAPOR on the other hand is highly flammable when combined with oxygen. To burn 1 liter of VAPORIZED gasoline it needs to be mixed with approximately 15 liters of air to provide the requisite oxygen for complete combustion. For these reasons there is no concern of igniting the fuel from the spark caused by the electric fuel pump.
YEAH like i think i have the situation where a debris is caught in the check valve because mine bleeds out overnight, like i can park the car and start it 2 hours later and its still fine but when parked overnight then the cranking time is longer. so question is that is there anything i can use to flush the debris out of the check valve ? i probably got it like this because i am too cheap and my gas is always on low and so i am sure dirt from the tank has gone and blocked the check valve, and this pump is relatively brand new. bought and installed like 6 month ago so i know it cant be broken yet.
Thanks for this. I just replaced a fuel pump. Old one had definitely failed. After 20 perfect kilometers on the new pump it started running rough, no power, slow to build revs and hard start. I have 55psi at the rail but an almost instant pressure drop. There are no leaks and I've checked the pressure regulator and its working. I assumed a failing pressure check valve in the pump but after this Im thinking maybe the regulator only looks like its working... hmmmmmmmmmm
I bought a new pump and when I checked it to see if it was actually pumping since I do hear it but nothing comes out... I noticed a small factory hole near the filter and its shooting a yet stream of gasoline out.. What should I do? Is it broken or I need to push something back in place? The pump is actually just like the video.
how long do the brushes last ? After how many hours / miles does it make sense to think about replacing the pump to prevent it to fail when you don´t need it ?
in the beginning of November I replaced the gas tank fuel hanger and pump on my chevy s10 pickup. December 6 my truck died. It refuses to start. When I turn the key on I can hear the pump run. but the truck won't start. If I dump gas into the throttle body the truck starts right up and then When the gas runs out it dies. How does a new fuel pump go bad in a month? I also replaced the gas filter and oil pressure sending unit and a new distributor. previous owner had installed a new fuel pump. Why does my truck hate fuel pumps?
it might be the fuel injectors are being disabled by the ecm this might happen if you have a problem with the security systems on the s10 and later model blazers there are video's here on u tube that explain about how to go about diagnosing this type of problem that is located inside the ignition switch contacts the security system on the s 10 and later models blazers can disable the fuel injectors but the pump will still run but the truck wont cause the fuel inectors are not enabled.
Most interesting video on the internet right now. I just can't find one about the transistor fuel pumps and why a universal on an 85 Nissan pickup keeps loosing fuel pressure from the tank up to the engine. I'm almost 100 percent sure it needs an inline check valve after the pump. I really think the auto parts store forgot that some filters used to double as a check valve. I don't understand why it's a discontinued part either it seemed to have a good purpose
Have a question. I think my fuel pump may be bad car hardly runs. So I test it with water and it only will pump if water is in the resovoir it's self and will hardley push any when trying to pump from screen inlet.. Does this mean my pump is bad?
@Bushougoma It may spark but because it is all immersed in the fuel, there is no oxygen present to burn the fuel with so if it was to spark, it would not ignite.
@EricTheCarGuy Well that's it Eric the truck hesitates horribly at times then it takes off like a bat out of hell.I pm you about that before and made sure it wasn't a timing chain. My next step is to start pulling plugs and to try and find the bad injector.
Thx alot Eric! I have an older saab, and I've found the most notorious part in my car is the fuel pump. I have been getting longer starts - about 6 seconds now - so its good to get some evidence of the fp from someone who knows them. Does a defect in the check valve mean replacement?
![ILLSLICK X YOUNGOHM - We're The same [Official Video]](http://i.ytimg.com/vi/yUJNkobYR0E/mqdefault.jpg)
You explained all components and functionality in under 10 min, and most importantly you answered all my questions.... Well done sir!
@knunne1 Thanks for that great comment, I'm actually looking into going back to Airtex to do some more of these videos so that is one request I hope to fill.
This is why I love your channel - very educational stuff, and you don't try to dumb it down like some other shows do.
Very detailed explanation. I’m sure there are a people who are interested to learn all about electric fuel pumps. It’s hard to look for videos like these so thank you for uploading it and satisfying people’s curiosities.
@1967800 That is the exact reason for these videos. Thanks very much for your comment.
@brian5446 Either that or you can just cycle the key before you crank the engine when you go to start the car, I did that for years on a car that I used to have as the pump still worked fine.
@TheTexasCoder That is very true, I like to get my info from the source whenever I can and this guy is about as close to the source as you can get from what I've seen. Thanks for the comment.
@aodhanof90 It's nice to get information direct from the source. Thanks for the comment.
This video defiantly confirms that I have a fuel injector problem with my truck and not a fuel pump check valve problem because of the bleed off time that my fuel pressure gauge was showing. When I tested my truck the pressure bled off immediately after shutting the truck off.I'm looking at getting new injectors and I know now its not the pump.Great video Eric and thanks for all the info.
@pathosbedlam Your most welcome and thank YOU for the comment.
Great video. It was nice to see the actual disassembled pump and to hear about the check valve, as that is something I needs attention on one of my vehicles.
@alundrasrt No need to worry about that as the pump is submerged in the gas in the tank which is what 'lubricates' (if you could call it that) and cools the assembly, priming it is not necessary at least with the pumps I've installed.
@barrioalto100 Glad you like them, thanks for the comment.
Eric this video has come in handy. I'm in the middle of a GM fuel pressure diagnosis and just how he explained the check valve and everything else has given me such a better understanding of the pump. Thanks and I'm literally still dirty...
Thanks to Airtex and ETCG for a great video. I am amazed at how, what is basically plastic and a motor can deliver combustible fluid so reliably. Hats off to Airtex's Engineering & Production's teams and their quality! I am guilty of not recognizing how hard and trouble free fuel pumps work. I enjoyed seeing how the Car's trouble symptoms related to the components in the pump and the various versions made as well as how they are tested. Again Great Video, more please!
@95ACM It's a common problem but as you can see the pump will still function without it but it will cause extended crank times.
Mr. Ulm is well spoken. I especially liked how he described the actual components in detail.
Interesting... If there were more people like you the world would be a better place... I like your passion and dedication... Keep it up
@Begbucks Yes they did have a very extensive diesel section at the facility, I didn't spend a whole lot of time there on this trip, perhaps the next if I get the opportunity.
@MrOne2watch It does sound like a possible check valve issue but use a fuel pressure gauge to confirm it. As for Airtex pumps I've never had a problem with them. I don't have a video on that particular replacement at this time sorry.
EricTheCarGuy z
@Bushougoma No, in fact the fuel flows right through the pump. Remember in order for combustion to take place you need O2 and if the pump is full of fluid there is no O2 for combustion to occur.
@nightmathzombieethan Indeed there is, thanks for the comment.
@1PossumJenkins Great information thanks for your comment.
@Filmaker25 That sure does help but the #1 cause of failure according to the people that I talked to was contamination of the pump with debris.
This guy is such an engineer. When he's talking to Eric he's looking at the disassembled fuel pump while answering the question and not even looking anywhere near Eric. The machines interest him more.
@tinydx95t2 I wouldn't condemn an injector right off if you don't have a problem with the way the engine runs, normally if an injector is that bad you will have a very wet spark plug and a misfire on the effected cylinder. You might want to try your test with the return line pinched off as it could be a fuel psi regulator problem. Good luck.
@TeDuaMalakie Remember it's immersed in gas so no air can get to it, you can't have combustion without O2.
@DrJerryrigger I do what I can, thanks for the comment.
@xmtc87x I love what I do so it's not hard at all. Thanks for the comment.
awesome video. I have been trying to find out why my 02 jeep wont start on the first try. people kept telling me its the fuel regulator that has the check valves. even the dealer couldnt tell me for sure, they just tell me to change everything 650.00! I will buy the airtex pump assy and put it in. Thanks for the great video Eric!
This video was very helpful in understanding the function of the electric fuel pump and how each component works.
@chopywatersofmantuki I'm sure there are but you should be able to clean it out, at least that's what I've done in the past.
@sbakar Hard to say, perhaps the clearances are at their limits or it's got contamination of some kind.
@Jx1x3 I don't think that would make much difference really but I've never tried it so I don't know.
@paul06660 If it's the original pump it's not likely that it's bad, in fact OE Honda pumps hardly ever go bad. You say the pressure is 40psi, but have you checked it during the extended crank? If not you might as the pump may be good but the check valve may be stuck not keeping pressure on the system after shut off. Lastly I HATE aftermarket distributors as I've seen nothing but problems with them, you may want to check your timing.
Now I don't need to take mine apart to see how it works. You saved me a afternoon and maybe a fuel pump! Thanks
@lol123321123321 That sounds like a check valve issue. Normally when pumps go bad they just don't run and cause a condition of no fuel pressure. I actually have another video with Airtex covering that procedure, How To Diagnose A Fuel Pump Failure.
@30GB No I don't think you can as it was not designed to move a fluid that thick or that hot.
@Sum2021 That's why I'm here, thanks for the comment.
@tookimonster333 I actually asked that very question in the other video the Engineering Tour.
Great video! Thank you AirTex and EricTheCarGuy...I love technical shows like this. Eric, all I have to say, after watching Curt's reactions to your questions, that man has FORGOTTEN MORE ABOUT FUEL PUMPS then you and I will ever learn :-)
Goodness, that's extremely complex! Its amazing these things don't fail more often. I've never owned a car that had a fuel pump fail until recently my 92 Astro van fuel pump started working intermittently. Kick the gas tank once or twice and it works again. Finally decided to change it. See this is why people want electric cars. wayyyyyyy fewer parts to fail lol.
I find it fascinating and a little counterintuitive that the brushes are submerged in gasoline with the rest of the pump. The brushes on most motors show visible spark, and those brushes on the fuel pump look smaller but similar. The only thing missing seems to be oxygen, and when the tank runs dry there will be air in the tank, too. Am I missing something?
spelunkerd my same concern or question,, how does that dont ignite the fuel??
@dandroz240 They make those there too, I hope to go back and show how those work next time.
Great clip,thanks. Is anyone able to answer a question which comes to mind while watching this; the float /level rheostat and the motor brushes and armature setups both appear to have active voltage circuits and (to me) apparent potential for arching or sparking.the fuel even passes THROUGH the motor ! Obviously this is a completely safe feature ,but I can't quite understand how these functions are included IN the actual tank,with no regard for a possible ignition of the fuel? Any explanation would be appreciated. Thanks in advance.
Notes: In many of these fuel pumps, there are a PAIR of one-way check valves. One is to maintain fuel pressure in the downstream fuel lines so as to keep from having long cranking times when you come back in the morning. The other check valve is for pressure relief in case the system is building up too much pressure for normal operation, it just bleeds off through the check valve which is oriented to release the excess pressure just below the normal system operating pressure. However, if a piece of debris gets caught in the rubber "seat" of the check valve, or the rubber of the check valves seat deteriorates over time sufficiently, the fuel pressure will bleed off in a certain amount of time when the vehicle is not in use. When you look at the top of the fuel pump and you see two different electrical connectors, one is of course for the power supply and the instrument cluster gauge, and the other is likely the electrical connect for the vapor sensor for the fuel tank.
Very clear description of all the parts and what they do
Sure would be nice if you guys made a pump that mounted OUTSIDE the fuel tank, perhaps inside a metal cage to protect it. The fuel could still flow-through for cooling. The ability to replace these things is now limited to few diys or an expensive trip to the shop.
Airtex guy did a beautiful presentation. Wish I was that good !
Eric, Great video, very informative. Thank you for all your hard work in shooting these videos, we need more like you in this business.
Cool video. Not something you usually think might be stopping your car from starting, until you see this and cross reference it with the symptoms your car is having. Luckily mine is still OK, but not fun to replace if yours is in need of repairs. Thanks for teaching me another thing about cars I might need if it stops working. :-)
Eric your channel is top-notch.
Thank you so much for sharing Eric! Wow, I believe the pressure relief valve went bad in my factory fuel pump. (2001 Chevy Cavalier 2.2). I hope you don't mind me sharing this but - I have never seen this before or I have not found any information on this type of fuel pump failure. I'm having a no start condition. I have spark everywhere spark should be. Testing the pump; the pump sound was normal, I could hear the pump running just fine. I found very low fuel flow, pressure at the filter, but not much fuel volume, I found it pumped about 1/2 quart in 5 minutes, when it should flow about 1 quart in 30 seconds. I very carefully removed the fuel pump and energized the fuel pump motor, the gas pressure was shooting out of the motor's top housing hole and barely going through the fuel line. I guess I have to replace either the pump or the fuel pump assembly.
Can't be just me, I have had several of these in a suburban, I drip the tank, clean the tank, replaced with a life time warranty Airtex ( I bought it when there was still lifetime warranties on these thank goodness) worked great for about 5 months and poof, gotta get a new one. 1997 suburban, 5 airtex pumps before I sold the truck off. 4 failures in 4 years not counting the last one I sold the truck off with or the first one that was OEM. I didn't have to clean the tank after that 1st time since it was clean as can be. the filters were not clogged, the just quit working. I am currently working in a GMC Yukon and decided to try a AC Delco. I am curious to see if it's works better.
Thanks! Now I know where the check valves at. Always informative!
@beefystik well that's what i understand from your comment , we all like the guy and i can tell you i have watched most of his videos maybe excepts the FATR's and i never remember he ever asked this or complained from repeated questions ! On the Contrary !! he always answer comments no matter how silly or lean or repeated they are! he even answers comments after while that makes you think he will never get back to them but he always does ! .
they know alot about pumps for people that can't build one that works. I had one doa. pushed 12psi new out of the box. second one I used lasted 25 miles and broke down on the side of the highway. I laid in gravel and broken glass to replace it with pos Carter pump that cost half as much and lasted 6 months. first two times I just needed to get by a few days, and they didn't even last that long. the Carter pump was the only one I could get same day where I was broke down.
BTW, airtek pumps were both all plastic drive mechanisms with thinner teeth then the brass assembly in the OEM Bosch and Carter pump. the airtek that lasted 25 miles was also really loud and pulled nearly 20 amps, the Carter pulled 9.6 amps while actually pumping.
even though the airtek couldn't start the car, it did have enough left in it to pump 10 gallons out of my full tank before I smashed it with a rock and left it with the broken glass.
this time I'm special ordering a walbro. the first one lasted 28 years and 320k miles, not minutes.
Yeah a whole lot of plastic in this video. Nobody cares about making stuff last anymore... Or perhaps they design them to fail.. more likely IMO.
I have a problem with in tank pump I want to use for inline pump. The bottom of pump has a large intake hole. There's also a very small hole in bottom plastic that is pressurized when pump runs. If I plug small hole pump fails and no fuel flow. Small hole open pump works but fuel comes out small hole & normal outlet on top. Obviously can't have fuel spraying all over from small hole. What's happening?
@s0nnyburnett I've been guilty of paying attention to machines instead of people myself so I guess I know how he feels.
@Ibringthetruth1 Feel free to stop by anytime.
Great video! Very informative. That's why I never try to drive my vehicles passed 1/4 if I can prevent it. Driving towards flat E is the primary reason fuel pumps fail prematurely!
I wonder if We change that "bag" or filter pick up it would help our pumps last longer since it wouldn't have to work so hard as it gets dirty...nice vid man! Im looking for your coolant vid haha
Great VID!!!!! Always wondered how a fuel pump works.
Marc
Is there a quality pump (motor) I can swap into my sending unit (airtech doesn't seem to be in business anymore)? Backstory, I really thought OEM would have been great but seems it's not what it used to be. I'm having a HELL of a time with a factory / OEM replacement fuel pump. I swapped out simply cause was old, preventative maintenance. I'm on my second OEM pump in 2 years. I keep going back and forth with the manufacturer that wants me to check various things but I've went through the line set, electrical circuit, regulator, injectors, rail, cannot find any other faults anywhere. Long story short, it's running 7 PSI lower than spec.
Awesome video, very good explanation of how fuel pump works.
Good job Eric, that's really cool
If the check valve is bad, then the hot engine starting gets difficult. The fuel pressure is lost quickly and with a hot engine, this results in fuel vapours forming in the fuel lines. This leads to hot engine restart a little longer.
Great video. Is there a way to test a used fuel pump motor to see how strong it is? I guess put it in the tank, do KOEO and KOER pressure tests at the rail then leave it over night to see if the check valve holds the pressure?
I have a 96 F250 w 60,000mi it has dual tanks. I'm experiencing low fuel pressure on both tanks. Front tank @18 psi and rear tank @ 28 psi. Both tanks hold pressure for awhile but not over night. Should I replace both pumps or is there a way to find out which pump is the problem?
Great video by the way!
Great video! Always wanted to know whats inside.
@donbehatin I have. I did a test with a fuel pressure gauge and I performed the test 6 times in a row and 4 out of the 6 times I performed the fuel pressure test the pressure leaked off.Plus I have been changing my oil about once a month because the oil smells like gas. I have great compression so its not rings.and I've looked at the rest of the fuel system and everything is good.The only 2 things that would cause readings like what I got is a faulty check valve or injectors.
@EricTheCarGuy What if you had an empty tank with just vapor in it? Couldn't that be an explosion hazzard if you get a spart or arc from the pump motor?
It helps to have a visual representation like this, and a "plain english" explaination of each component. I can't learn shit from just a bunch of text, a have to at least see a video like this, but I prefer to actually get my hands on it at some point.
Now I see why modern designs incorporate a fuel filter proximal to the pump, to keep debris from clogging the pump turbines. Too bad the new fuel filters are so hard to get to....
good video.
last week i destroyed two of this type of motors to know what is there inside mees how it pumps fuel when it submerged in fuel.
but you given good description about this motors.
thanks.
none of my cars have any of those stupid fuel pump modules. they simply have the fuel pump that he is holding in his hand hanging from the fuel pump sending unit. i dont know why they went to the module setup but they are very expensive to replace, somewhere around 300 bucks. another reason why i like older cars, parts are allot cheaper and things are generally simpler to work on
i have a 2005 Chevy equinox the fuel pump went out does the electrical pump come with the fuel pump also or does it have to even be replaced? or just the fuel pump
"I have a question about fuel pump design. I was wondering why fuel pumps are designed to use the fuel itself as a lubricant and coolant. Why is this so? Most other electric motors I've seen don't need any cooling to operate continuously. Also, since fuel is going through the motor brushes, wouldn't there be a spark there while the electric motor is spinning? Wouldn't that ignite the fuel? I don't know much about these things..."
most electric motors have a lubricant inside them, unfortunately gasoline acts as a solvent and washes off the lubricants. So the pumps are designed to use gasoline as a lubricant instead. Many fuel pump motors are quite powerful for their size, and run at 100% duty cycle (the run continuously) and will overheat without a constant flow of cool fuel. Most electric motors that run for extended periods with 100% duty cycle have some form of cooling. also keep in mind some electric motors are air cooled without a fan and may or may not use a heat sink to aid in cooling depending on how much heat they put out.
Liquid gasoline and diesel is non flammable. In fact assuming there is no vapors sitting on top of the fuel you can throw a lit match into a bucket of gasoline and it will put out the match. Gasoline VAPOR on the other hand is highly flammable when combined with oxygen. To burn 1 liter of VAPORIZED gasoline it needs to be mixed with approximately 15 liters of air to provide the requisite oxygen for complete combustion. For these reasons there is no concern of igniting the fuel from the spark caused by the electric fuel pump.
YEAH like i think i have the situation where a debris is caught in the check valve because mine bleeds out overnight, like i can park the car and start it 2 hours later and its still fine but when parked overnight then the cranking time is longer. so question is that is there anything i can use to flush the debris out of the check valve ? i probably got it like this because i am too cheap and my gas is always on low and so i am sure dirt from the tank has gone and blocked the check valve, and this pump is relatively brand new. bought and installed like 6 month ago so i know it cant be broken yet.
@dalix1951 Thank you!
great question about check valve symptoms!
Very cool. Very detailed and helpful. Thanks Eric!
Thanks for this. I just replaced a fuel pump. Old one had definitely failed. After 20 perfect kilometers on the new pump it started running rough, no power, slow to build revs and hard start. I have 55psi at the rail but an almost instant pressure drop. There are no leaks and I've checked the pressure regulator and its working. I assumed a failing pressure check valve in the pump but after this Im thinking maybe the regulator only looks like its working... hmmmmmmmmmm
Can you ask him please what is the white cover on the rotating armature that covers the wires
I bought a new pump and when I checked it to see if it was actually pumping since I do hear it but nothing comes out... I noticed a small factory hole near the filter and its shooting a yet stream of gasoline out.. What should I do? Is it broken or I need to push something back in place? The pump is actually just like the video.
how long do the brushes last ? After how many hours / miles does it make sense to think about replacing the pump to prevent it to fail when you don´t need it ?
How come the motor brushes don't arc and ignite the fuel? I never thought about that until now. Is is because there is no air in there?
in the beginning of November I replaced the gas tank fuel hanger and pump on my chevy s10 pickup. December 6 my truck died. It refuses to start. When I turn the key on I can hear the pump run. but the truck won't start. If I dump gas into the throttle body the truck starts right up and then When the gas runs out it dies. How does a new fuel pump go bad in a month? I also replaced the gas filter and oil pressure sending unit and a new distributor. previous owner had installed a new fuel pump. Why does my truck hate fuel pumps?
it might be the fuel injectors are being disabled by the ecm this might happen if you have a problem with the security systems on the s10 and later model blazers there are video's here on u tube that explain about how to go about diagnosing this type of problem that is located inside the ignition switch contacts the security system on the s 10 and later models blazers can disable the fuel injectors but the pump will still run but the truck wont cause the fuel inectors are not enabled.
Most interesting video on the internet right now. I just can't find one about the transistor fuel pumps and why a universal on an 85 Nissan pickup keeps loosing fuel pressure from the tank up to the engine. I'm almost 100 percent sure it needs an inline check valve after the pump. I really think the auto parts store forgot that some filters used to double as a check valve. I don't understand why it's a discontinued part either it seemed to have a good purpose
So if i have a working fuel pump, but its not giving me enought pressure, what is the part that i have To replace In that motor?
That guy knows his pumps!
very good break down
Have a question. I think my fuel pump may be bad car hardly runs. So I test it with water and it only will pump if water is in the resovoir it's self and will hardley push any when trying to pump from screen inlet.. Does this mean my pump is bad?
maybe
Good video.
@Bushougoma It may spark but because it is all immersed in the fuel, there is no oxygen present to burn the fuel with so if it was to spark, it would not ignite.
@EricTheCarGuy Well that's it Eric the truck hesitates horribly at times then it takes off like a bat out of hell.I pm you about that before and made sure it wasn't a timing chain. My next step is to start pulling plugs and to try and find the bad injector.
If you keep your fuel level up is that all you need to do to keep the fuel pump going? How many miles should you get with any fuel pump?
Very good video.
Eric, how to "load" the new pump if it's new in order to lubricate at the first rpms? Any tips? Cheers.
Thx alot Eric! I have an older saab, and I've found the most notorious part in my car is the fuel pump. I have been getting longer starts - about 6 seconds now - so its good to get some evidence of the fp from someone who knows them. Does a defect in the check valve mean replacement?
Wish you would have done a video between a good airtex pump and a cheap pump found from a random seller on ebay or amazon.
Get a Delphi or Carter, not Airtex!
Hey that was a great video Eric, thanks for putting that together :-)