I am not experienced with RC vehicles yet but am thinking of getting a 4 channel plane with a live feed video camera on it. Extremely good video work to whoever did this video. Wow. Quality camera, good video editing, clear step by step instruction, clear words, necessary equipment, ect.... Very good video. I'm into drag racing but it was very interesting to see how similar these engines are to full size units.
Thanks for responding so quickly. I'll give it a try. I got the cover off but the cam is stuck good. The cam followers were a bear to get out. A heavy magnet helped after I worked them up and down a while. I'll check out your site, Thanks again.
There is no side load on the wrist pin so no wear of the pads. The pads used to be brass many years ago and worked without issue. OS made a FS-26 and FS-40 specifically for cars. The FS-26S-CII is still made but not sold in the US. People have modified other airplane engines for car use.
@7bikerboy7 I happen to have an FS-120S-III apart and it does have two gaskets. I didn't measure, but one looks like 0.2mm and the other 0.4mm. The listing on Tower shows two gaskets as well as the OS manual.
@MaxwellForce That happens sometimes due to tolerances or corrosion. The the flame can unevenly heat the housing and may not expand correctly to release the bearing. Thought the 91VRDF with it's bolt on front end shouldn't be a problem. The worst thing that can happen by hitting the case heard is distorting it or the mating surfaces. It's probably fine. Only time will tell.
I too have a 120 pumped and It's been sitting for quite a while, really gummed up. Any suggestions on a soaking solution to loosen things up? I don't want to force anything but I can't even get the cam cover off, and yours slipped right off. I'm seriously bummin'. I have lots of carbon in the combustion chamber and junk all over the crank and cam followers. Nothing moves hardly at all. Any help I really appreciate. Good vidoe by the way, lots of help right there. Thanks.
thanks, so there are just a couple of plastic caps on each end of the pin to keep it in place, does they wear out due to friction with the cylinder liner? well, about the parts my crappy force two stroke 0.15 has about 20 pieces less than that four stroke but is 20 times less reliable as well, i would reallyl ike to try a four stoke conversion for my 1/10 buggy :)
@7bikerboy7 Many use airtool oil. In the FS-120S-III there isn't actually any contact between the crankcase and regulator. The diaphragm in the pump should handle it as it's mylar or something. Incompatible oils can turn to sludge in the crankcase. People have been using engine and airtool oil as after-run oils for years, seemingly without issue, other than pumped engines, in particular YS.
@Luvtoflyhelis Use the drywall screw or a screw extractor to get the wrist pin out. If that doesn't work grind a fine taper on the drywall screw to get a better grip. If that doesn't work, heat the piston, there is oil residue or corrosion holding it in. If it's badly corroded it might not be possible to get it out and the only option will be cutting the rod. I've only had to cut one rod out of probably 30 engines.
Nice Video Greg. Have never attempted to take apart a 4 stroke; used to race RC cars & have plenty of experience disassembling 2 strokes. I have a pumped OS 155@ engine that has been sitting for 3yrs & will attempt disassembly sometime soon. Is there any info you can give me before I tackle it ? Can you tell me where you purchased your torque wrench, & what are the torque values for most of the screws ?
I disassembled my OS91 VRDF engine to change the main bearing. I had a lot of trouble with the main bearing. It just wouldn’t budge. I used an open flame and gently heated the crank case of course. I eventually got it out, but I had to use more then a slight tab. I really had to knock it really hard before the bearing got lose. Now I am worried that I might have damaged the engine, is there any way to know or see if any damage has occurred. The engine seems to run just fine afterwards.
This engine is pristine and very easy to disassemble try one that has got some run time and residual fuel and castor oil in it helpful in showing how it comes apart but in reality most are not that easy.
hi, is there a quick solution if the rocker arms are not moving and there is no compression on the engine?? or does it mean a complete dissemble? great video
The cam followers are stuck. You can push on the rod side of the lifter and if followers loosen easily ,I'd say you're fine. If still stuck, try heating the engine or putting fuel or solvent down the pushrod tubes to free the followers.
Cheers thanks mate!!! Ten minutes of repetition and the rockers are moving freely!! OS 26 running like a charm.. Way better than a complete disassembly!!
Great video. However I have one problem and I hope you have a solution. The piston wrist pin on my 52 is old and will not come out. The pad came right out. I have tried heating the pin with a heat gun and I have soaked it in wd-40. Any suggestions you have will be greatly appreciated.
If a heat gun wasn't hot enough, the next step is a torch. It doesn't take a big flame. If congealed oil is holding it, this will work. For soaking, acetone does an excellent job cutting oil and castor.
hi, great vid! can you please tell me more about your little heater thing. I have lots of rc engines and have never seen one like it. aside from very specific bearing pullers this technique was fantastic!
hi, question..i have an os fs 120III with pump. Do you know if this engine has 2 head gaskets or one, cause when i was cleaning i couls swear i only took off one but later found 2 on the napkin.
To degum and clean an Rc engine…get an old slowcooker. Disassemble the engine as far as possible. Place the parts in the slowcooke. Cover the parts in 100% auto antifreeze - the green stuff without water. Cook for 12 to 24 hours on low. Clean with a toothbrush and repeat as necessary. I saw this on another Internet forum and I kwow others that have cleaned auto Caribs the same way.
Procedures will have to be changed some for anything other than an almost new engine. Any engine with some use will have varnish and other contamination holding the parts together. That makes disassembly more difficult. Will need at least an arbor press and some experience. If you have an old engine that you want to rebuild, buy a junk motor and learn on that so you don't ruin your good motor.
Josiah Aston I almost always disassemble to clean. Heat will soften old oil and you can remove the rocker cover and back plate and add fresh fuel or acetone to dissolve the old oil residue.
Josiah Aston Yes, any engine oil will work. In theory methanol soluble oil would be better, but most after run oil is just common oil, and many people use ATF. Maybe a teaspoon total. Lube the rockers separately as oil doesn't have a direct path from the crankcase.
Fine. Now show how to take apart a gummed up, used and abused engine, with stuck wrist pin, damaged bolt heads, cam cover glued in place, etc, not a brand new one just out of the box!
If you have trouble with a sticky engine, heat/solvent will solve virtually all issues. The wrist pin can be a pain, I but have never had trouble with anything else. I typically drill to remove a damaged screw head.
I was trying to find out why my OS .82 four stroke wont start after 6 months of sitting and I found this. Great disassembly vid.
I am not experienced with RC vehicles yet but am thinking of getting a 4 channel plane with a live feed video camera on it.
Extremely good video work to whoever did this video. Wow. Quality camera, good video editing, clear step by step instruction, clear words, necessary equipment, ect....
Very good video. I'm into drag racing but it was very interesting to see how similar these engines are to full size units.
Finally! an engine rebuilder on youtube that knows what he's doing! and has great camera work! Thank you! and btw i love these small 4 stroke engines
Thanks for responding so quickly. I'll give it a try. I got the cover off but the cam is stuck good. The cam followers were a bear to get out. A heavy magnet helped after I worked them up and down a while. I'll check out your site, Thanks again.
There is no side load on the wrist pin so no wear of the pads. The pads used to be brass many years ago and worked without issue.
OS made a FS-26 and FS-40 specifically for cars. The FS-26S-CII is still made but not sold in the US. People have modified other airplane engines for car use.
@7bikerboy7 I happen to have an FS-120S-III apart and it does have two gaskets. I didn't measure, but one looks like 0.2mm and the other 0.4mm. The listing on Tower shows two gaskets as well as the OS manual.
@MaxwellForce That happens sometimes due to tolerances or corrosion. The the flame can unevenly heat the housing and may not expand correctly to release the bearing. Thought the 91VRDF with it's bolt on front end shouldn't be a problem. The worst thing that can happen by hitting the case heard is distorting it or the mating surfaces. It's probably fine. Only time will tell.
I too have a 120 pumped and It's been sitting for quite a while, really gummed up. Any suggestions on a soaking solution to loosen things up? I don't want to force anything but I can't even get the cam cover off, and yours slipped right off. I'm seriously bummin'. I have lots of carbon in the combustion chamber and junk all over the crank and cam followers. Nothing moves hardly at all. Any help I really appreciate. Good vidoe by the way, lots of help right there. Thanks.
thanks, so there are just a couple of plastic caps on each end of the pin to keep it in place, does they wear out due to friction with the cylinder liner? well, about the parts my crappy force two stroke 0.15 has about 20 pieces less than that four stroke but is 20 times less reliable as well, i would reallyl ike to try a four stoke conversion for my 1/10 buggy :)
@7bikerboy7 Many use airtool oil. In the FS-120S-III there isn't actually any contact between the crankcase and regulator. The diaphragm in the pump should handle it as it's mylar or something. Incompatible oils can turn to sludge in the crankcase. People have been using engine and airtool oil as after-run oils for years, seemingly without issue, other than pumped engines, in particular YS.
@Luvtoflyhelis Use the drywall screw or a screw extractor to get the wrist pin out. If that doesn't work grind a fine taper on the drywall screw to get a better grip. If that doesn't work, heat the piston, there is oil residue or corrosion holding it in. If it's badly corroded it might not be possible to get it out and the only option will be cutting the rod. I've only had to cut one rod out of probably 30 engines.
Nice Video Greg. Have never attempted to take apart a 4 stroke; used to race RC cars & have plenty of experience disassembling 2 strokes. I have a pumped OS 155@ engine that has been sitting for 3yrs & will attempt disassembly sometime soon. Is there any info you can give me before I tackle it ? Can you tell me where you purchased your torque wrench, & what are the torque values for most of the screws ?
I disassembled my OS91 VRDF engine to change the main bearing. I had a lot of trouble with the main bearing. It just wouldn’t budge. I used an open flame and gently heated the crank case of course. I eventually got it out, but I had to use more then a slight tab. I really had to knock it really hard before the bearing got lose. Now I am worried that I might have damaged the engine, is there any way to know or see if any damage has occurred. The engine seems to run just fine afterwards.
Amazing how they make these little engines almost like car engines with the valves and head, all those little precision parts!
Nice. Make other part of it for refitting it.which scroodriver n key required for opening it.please reply
I have reassembly videos. Being Japanese, these require metric tools.
Awesome tuto! How do i extract the little bearing from camshaft?
@rcdieselrc ok thank you, i used oil used for air tools, what do you think?
This engine is pristine and very easy to disassemble try one that has got some run time and residual fuel and castor oil in it helpful in showing how it comes apart but in reality most are not that easy.
The hardest part to remove will be the wrist pin.
Very interesting seeing how these things are built, thank you :)
hi, is there a quick solution if the rocker arms are not moving and there is no compression on the engine?? or does it mean a complete dissemble? great video
The cam followers are stuck. You can push on the rod side of the lifter and if followers loosen easily ,I'd say you're fine. If still stuck, try heating the engine or putting fuel or solvent down the pushrod tubes to free the followers.
Cheers thanks mate!!! Ten minutes of repetition and the rockers are moving freely!! OS 26 running like a charm.. Way better than a complete disassembly!!
nice vice did you make that?
Great video. However I have one problem and I hope you have a solution. The piston wrist pin on my 52 is old and will not come out. The pad came right out. I have tried heating the pin with a heat gun and I have soaked it in wd-40. Any suggestions you have will be greatly appreciated.
If a heat gun wasn't hot enough, the next step is a torch. It doesn't take a big flame. If congealed oil is holding it, this will work. For soaking, acetone does an excellent job cutting oil and castor.
hi, great vid! can you please tell me more about your little heater thing. I have lots of rc engines and have never seen one like it. aside from very specific bearing pullers this technique was fantastic!
The heater is a small lab type hot plate, nothing special.
hi, question..i have an os fs 120III with pump. Do you know if this engine has 2 head gaskets or one, cause when i was cleaning i couls swear i only took off one but later found 2 on the napkin.
Where did you get that little vice? I could so use one of those.
To degum and clean an Rc engine…get an old slowcooker. Disassemble the engine as far as possible. Place the parts in the slowcooke. Cover the parts in 100% auto antifreeze - the green stuff without water. Cook for 12 to 24 hours on low. Clean with a toothbrush and repeat as necessary. I saw this on another Internet forum and I kwow others that have cleaned auto Caribs the same way.
god, this is a really complicated rc engine. so basically there are no snap rings to hold the wrist pin inside the piston?
@tycomypuppy1 There are only a few more parts. once you learn how it all works and goes together, no problem at all.
wow that looks way more complicated than my 2 stroke.. or are looks decieving?
You are a real genius :) thanks for the vid, i'm looking for the same but for a 2 strokes version (OS-55 AX) :)
Where can I get engines like that?
cara, muito bom o seu video. me ajudou muito. parabens.
guy, very good your video. helped me a lot. congratulations.
How does the cam turn? I've been trying to figure that out.
The cam is driven off the crank by helical gears.
Thank you!! very nicely explained. Too bad though that older engines put up much more of a fight.
Procedures will have to be changed some for anything other than an almost new engine. Any engine with some use will have varnish and other contamination holding the parts together. That makes disassembly more difficult. Will need at least an arbor press and some experience. If you have an old engine that you want to rebuild, buy a junk motor and learn on that so you don't ruin your good motor.
has that engine ran
Great video...good job..new subscriber
How do you fix seized up engines because I have one that has not Ben run in years and it moves just VERY tight?!
Josiah Aston I almost always disassemble to clean. Heat will soften old oil and you can remove the rocker cover and back plate and add fresh fuel or acetone to dissolve the old oil residue.
Ok. And another thing one of the screws on the carb has a striped head and I need to get it off what should I do now?
Josiah Aston Use a file or dremel tool with a cut off disk to grind a slot in the head
Do I need to lubricate when I reassemble it if so what kind of oil and how much
Josiah Aston Yes, any engine oil will work. In theory methanol soluble oil would be better, but most after run oil is just common oil, and many people use ATF. Maybe a teaspoon total. Lube the rockers separately as oil doesn't have a direct path from the crankcase.
@pipes81111 This was a new engine I disassembled for modifications.
Where did you get the vice? Thanks
Just a cheapo China 2" grinding vise.
A four stroke engine does have many more parts than a two stroke engine. No snap rings in this engine. The plastic pads serve the same purpose.
It's a machinist's grinding vise. A Chinese import costs under 40USD.
what you parsul me engine palees?
Fresh fuel into the crankcase and heat from a heat gun will loosen things up. Please contact me through my website for further questions.
very informative ..thanks
thanks for the vid now i know a 4 stroke looks like apart
Thanks for the comments everyone. I'm getting ready to do a series on Saito four strokes soon.
berapah harga untuk mesin seperti itu boss,,,
No. It's just a 2" grinding vice.
Nice Video a verry thanks
Reassembly videos are also up.
nice job!!
@rcdieselrc thank you
think ill invest in one thanks good vid
very good ,muito bom.
very cool :)
gulp... gulp... remove the pushrods... gulp... the valve keepers... gulp... hehehe... gulp... kinda like this video... gulp!
Kheyle mr30
??
Fine. Now show how to take apart a gummed up, used and abused engine, with stuck wrist pin, damaged bolt heads, cam cover glued in place, etc, not a brand new one just out of the box!
If you have trouble with a sticky engine, heat/solvent will solve virtually all issues. The wrist pin can be a pain, I but have never had trouble with anything else. I typically drill to remove a damaged screw head.
Kitanaka ha