This was very informative and explained well. My Jeep dealer found two loose/worn wrist pins on my 2001 Cherokee xj 4x4 at 188 k miles. I've drove it another thousand with no change in sound or performance. Bought it with 187 and the sound was present then. Saving up for a rebuild.
Floating pins have a retaining device keeping the pin in the piston. Snap rings, spiro-locks bushings etc. if you take one end loose and you can slide the pin out then, you have floating pins
@@FabRaceModRepeat I have a set of rods and pistons but the wrist pin does not slide into the rod. Even with some pressure with my hand. The pistons do have c clips with them. The rods do have 2 oil passages in the bottom of the small bore and the bronze/ copper insert. Im not sure if the small bore needs to get bored a bit or if they should come perfect and ready to go. Is it possible a rod can be press fit and the piston still have the c clips? Thanks. I appreciate your input im pretty stuck on this for a few days.
@Bullikid If they are new or the rods and pistons came from 2 different sources. It sounds like you need to have the bronze rod bushing honed to size. New ones are usually a bit tight.
@@FabRaceModRepeat the rod and piston came together from the same company as a set. I micd the oem pin and new pin and new pin is .025 bigger. The oem pin floats nice and smooth with the new rod. So I’m not sure if I should heat and and try installing or go to machine shop to hone/ bore out to spec. Weird never thought this would be a issue. Building my first motor.
nice video, clear explanation on fully floating piston pins. worth noting that press fit piston pins as shown in this video as also known as semi floating pins. fixed or stationary pins would be when the piston is fixed to the piston but is able to turn/spin in the connection rod.
Good morning, Thanks, glad you enjoyed the video. Yes that is the third type piston pin. I’ve seen that set up in very early engines and some industrial applications.
Thank you for the explanation. I recently experienced the problem of press fit piston pin that slided till scratching the cylinder. What are the probables causes of the sliding movement?
Thanks for watching! Typically when the pin slides over like that the rod has lost its grip (press fit) on the pin. When this happens the pin slowly walks over to one side or the other, eventually contacting the cylinder wall. High RPM and hard driving can contribute to this situation. Possibly the pin fit could’ve pin a bit loose when the pistons were installed.
Thank you for the explanation. In fact, it is possible that the marinization of my onboard 17hp/3600rpm engine, principally desined for agricol machines like tractors, has some limitations in terms of materials resistance throughout the use in marine conditions. The former same engine lasted 14 years (previous owners) and this one is currently aged 14 and 800h. Btw, I decided to repair. My mechanic suggested me to modify the piston and the rod to put seegers and change from a press fit pin to a full floating one. I wish good luck to myself 😊👋🤞
Great info vid ,,,I wonder if you can help me out ? If I keep my engine at a steady 2000 RPM and accelerate to like 2500 2700 RPM its like a hear a faint slight growl would that be the wrist pin ?,,, The engine is a 6.0 LQ9
Can you explain the installation for a press fit piston and floating rod installation? I have this arrangement on my Onan generator and I have the new rod ready for installation
Morning Don, Thanks for watching. I have only done that style once many years ago, on a hit an miss boat engine. The procedure for that on was: First clearance the rod bushing to fit the pin. The pin then pressed into the piston (without heating piston) to the specified depth. It used small cotter pins to insure the piston pins didn’t work back out. With all that said doing a google search for Onan piston installation would be worth while.
I’m going to use push in pins so should I use clips in order to prevent the pin from working it’s way to the side and scarring the cylinder? Or is it okay to not use a retaining clip if it is a press in pin.
The press pin set up doesn’t require a retaining clip. I never really thought about adding a clip to a press setup. If I was going to have the added weight of the clips I’d go full floating pins.
What the difference in the from a pin that floats and one that's pressed? ...other than how they are assembled and work. Can the same pin be used as floater or pressed?
Great question. How they’re retained is the main differences. The same pin can be used for both application (Varys by manufacture). The floating pins are usually a bit shorter than press in.
Very informational, thank you. I had my pistons ceramic coated but during the process, the wrist pins were not marked to each piston. Does it matter which piston the wrist pins go back in? They are full floating.
Michael Matagrano Thanks for watching. If you have not had the pins fit yet it doesn’t matter. If they have been fit, either at the factory or by the engine builder it most likely does matter. This would be a good time to do some clearance checking.
@@FabRaceModRepeat They are the original pins and rods (LS 5.3 Gen IV) and the pins slide in just fine with no binding. They were all fine before the rebuild and have about 160,000 miles on them.
Michael Matagrano As a general rule it’s best to keep used parts together and in the same orientation. If you have the measuring equipment, I would check the clearance of both the pins and the hole in the pistons. It’s cheap insurance. Then put the pins in the piston they fit best.
If you ask me, I would say, Yes, it does matter. Every part of an engine has been warn to its specific place. This is what happens when you break -in an engine for the first time. The piston pins will be worn to the specific piston and connecting rod. So it's important to put them back into the same place and direction where they came out of the piston and connecting rod.
I got new pistons and going to reuse stock rods stock is pressed and the new pistons are floating ones they come with the wrist pin am I ok to use the new ones
I'm working on a '56 Pontiac with full floating pistons.I want to reuse my pistons but I noticed on one piston the wrist pin won't rotate on the rod and on another one it won't rotate in the piston.I tried soaking them with lube,letting them sit and then working them again but they won't budge.What do you suggest?
I have an engine with a floating wrist pin setup however the con rod is severely scored and uneven so the wrist pin just binds in it, making the only pivot point in the piston. Do you think it’s okay to run like that?
Morning By “52 series” I assume you mean JE Piston, wrist pins. With that said JE makes a great product. I would check their website or call the tech line about the best pin for the application. Pins vary greatly between applications, for example: a very lite rotating assembly in a 2bbl late model stock car and a BIG power adder outlaw 10.5. car.
![Button Pistons | What Do YOU Know About Wrist Pin Retainers [TECH TALK]](http://i.ytimg.com/vi/h5E7es7uOTs/mqdefault.jpg)
![Button Pistons | What Do YOU Know About Wrist Pin Retainers [TECH TALK]](/img/tr.png)
As someone going through school and studying piston related information at the moment, this is a perfect explanation of it all.
Glad you enjoyed it.
love all the explanations of this guy, very informative
This was very informative and explained well. My Jeep dealer found two loose/worn wrist pins on my 2001 Cherokee xj 4x4 at 188 k miles. I've drove it another thousand with no change in sound or performance. Bought it with 187 and the sound was present then. Saving up for a rebuild.
Glad it helped
Thanks for watching
Thank you. It helped me understand full-floating Piston Pins for my Aviation class.
That’s great!
Thanks for watching
How can you physically tell the difference between pressed vs floating rod
Floating pins have a retaining device keeping the pin in the piston. Snap rings, spiro-locks bushings etc. if you take one end loose and you can slide the pin out then, you have floating pins
@@FabRaceModRepeat I have a set of rods and pistons but the wrist pin does not slide into the rod. Even with some pressure with my hand. The pistons do have c clips with them. The rods do have 2 oil passages in the bottom of the small bore and the bronze/ copper insert. Im not sure if the small bore needs to get bored a bit or if they should come perfect and ready to go. Is it possible a rod can be press fit and the piston still have the c clips? Thanks. I appreciate your input im pretty stuck on this for a few days.
@Bullikid
If they are new or the rods and pistons came from 2 different sources. It sounds like you need to have the bronze rod bushing honed to size. New ones are usually a bit tight.
@@FabRaceModRepeat the rod and piston came together from the same company as a set. I micd the oem pin and new pin and new pin is .025 bigger. The oem pin floats nice and smooth with the new rod. So I’m not sure if I should heat and and try installing or go to machine shop to hone/ bore out to spec. Weird never thought this would be a issue. Building my first motor.
@BulliKid
Use the pins that came with the pistons.
Go to the machine shop it’s typically $50-80 to fit the pin.
PS
It’s money well spent
nice video, clear explanation on fully floating piston pins.
worth noting that press fit piston pins as shown in this video as also known as semi floating pins.
fixed or stationary pins would be when the piston is fixed to the piston but is able to turn/spin in the connection rod.
Good morning,
Thanks, glad you enjoyed the video. Yes that is the third type piston pin. I’ve seen that set up in very early engines and some industrial applications.
Simple and efficient explanation, thank you
Glad you enjoyed it.
Thanks for the comment
thank you very much for explaining. this was very helpful.
Thanks for watching glad I could help
great explanation!
@@OldSchoolNoe Thanks!
Thank you for the explanation. I recently experienced the problem of press fit piston pin that slided till scratching the cylinder. What are the probables causes of the sliding movement?
Thanks for watching!
Typically when the pin slides over like that the rod has lost its grip (press fit) on the pin. When this happens the pin slowly walks over to one side or the other, eventually contacting the cylinder wall. High RPM and hard driving can contribute to this situation.
Possibly the pin fit could’ve pin a bit loose when the pistons were installed.
Thank you for the explanation. In fact, it is possible that the marinization of my onboard 17hp/3600rpm engine, principally desined for agricol machines like tractors, has some limitations in terms of materials resistance throughout the use in marine conditions. The former same engine lasted 14 years (previous owners) and this one is currently aged 14 and 800h. Btw, I decided to repair. My mechanic suggested me to modify the piston and the rod to put seegers and change from a press fit pin to a full floating one. I wish good luck to myself 😊👋🤞
Great info vid ,,,I wonder if you can help me out ? If I keep my engine at a steady 2000 RPM and accelerate to like 2500 2700 RPM its like a hear a faint slight growl would that be the wrist pin ?,,, The engine is a 6.0 LQ9
Growling sound in the acceleration curve is usually a rocker trunion going bad.
@@FabRaceModRepeat Thank you for the reply ,,I was worried it was a wrist pin
Can you explain the installation for a press fit piston and floating rod installation? I have this arrangement on my Onan generator and I have the new rod ready for installation
Morning Don,
Thanks for watching.
I have only done that style once many years ago, on a hit an miss boat engine. The procedure for that on was:
First clearance the rod bushing to fit the pin. The pin then pressed into the piston (without heating piston) to the specified depth. It used small cotter pins to insure the piston pins didn’t work back out.
With all that said doing a google search for Onan piston installation would be worth while.
I would imagine clips are not generally used with press-fit rods, as the pin would wear/bind torsionally on the clips. Is this a correct assumption?
The press fit holds the pin in. No clips required.
can I put gen 4 LS floating pistons on my gen 3 press fit rods?
Are the pins ever pressed into the piston and float in the small end of the rod?
Thanks for watching!
In some industrial and early automotive applications, the pin is pressed in the piston with a floating rod.
Thanks so much for the solid info!
Commie Killer
Thanks for watching! Glad it helped.
So in the full floating type the pin can move freely in the piston and around the pin?
Yes
The pin spins freely in both the piston and the rod. It can also walk right left a bit in most cases.
I’m going to use push in pins so should I use clips in order to prevent the pin from working it’s way to the side and scarring the cylinder? Or is it okay to not use a retaining clip if it is a press in pin.
The press pin set up doesn’t require a retaining clip. I never really thought about adding a clip to a press setup. If I was going to have the added weight of the clips I’d go full floating pins.
I have sum d16a1. High Compression piston I'm trying to put on my d16y7 rods how can I remove the rods to put my high compression piston on ???
I believe you have a Honda?
What the difference in the from a pin that floats and one that's pressed? ...other than how they are assembled and work. Can the same pin be used as floater or pressed?
Great question.
How they’re retained is the main differences. The same pin can be used for both application (Varys by manufacture). The floating pins are usually a bit shorter than press in.
@@FabRaceModRepeat thanks
Very informational, thank you. I had my pistons ceramic coated but during the process, the wrist pins were not marked to each piston. Does it matter which piston the wrist pins go back in? They are full floating.
Michael Matagrano
Thanks for watching.
If you have not had the pins fit yet it doesn’t matter. If they have been fit, either at the factory or by the engine builder it most likely does matter.
This would be a good time to do some clearance checking.
@@FabRaceModRepeat They are the original pins and rods (LS 5.3 Gen IV) and the pins slide in just fine with no binding. They were all fine before the rebuild and have about 160,000 miles on them.
Michael Matagrano
As a general rule it’s best to keep used parts together and in the same orientation. If you have the measuring equipment, I would check the clearance of both the pins and the hole in the pistons. It’s cheap insurance. Then put the pins in the piston they fit best.
If you ask me, I would say, Yes, it does matter. Every part of an engine has been warn to its specific place. This is what happens when you break -in an engine for the first time. The piston pins will be worn to the specific piston and connecting rod. So it's important to put them back into the same place and direction where they came out of the piston and connecting rod.
What do you think is a better solution?
Floating or heated?
I go for the floating setup on 99% of my builds.
Thank you sir
You’re very welcome. Thanks for watching.
I got new pistons and going to reuse stock rods stock is pressed and the new pistons are floating ones they come with the wrist pin am I ok to use the new ones
Great question.
I have seen this done. However, If I were doing the build; I would have the rods bushed and make it a full floating set up.
I'm working on a '56 Pontiac with full floating pistons.I want to reuse my pistons but I noticed on one piston the wrist pin won't rotate on the rod and on another one it won't rotate in the piston.I tried soaking them with lube,letting them sit and then working them again but they won't budge.What do you suggest?
Chief 1
Sounds like your going to have to press them out.
Can you use a press for press fit wrist pins also
Joe Alfaro
Good morning and great question,
It’s not recommended because a “cold” press is not as tight as a “hot press”.
I have an engine with a floating wrist pin setup however the con rod is severely scored and uneven so the wrist pin just binds in it, making the only pivot point in the piston. Do you think it’s okay to run like that?
@mondude9754
Thanks for watching however, NO do not run your engine with a rod in that condition!
Can the pin be a little loose when cold, in my motorcycle?
Loose as in pin wiggles in the hole?
@@FabRaceModRepeat yes there is a little play and wear.
I’d replace it.
It’ll start to pin knock, and that will tear up the piston
301st subscriber here 🎉
Davis John
Happy New Year!
Welcome to the channel
R the 52 series wrist pins any good?
Morning
By “52 series” I assume you mean JE Piston, wrist pins.
With that said JE makes a great product. I would check their website or call the tech line about the best pin for the application. Pins vary greatly between applications, for example: a very lite rotating assembly in a 2bbl late model stock car and a BIG power adder outlaw 10.5. car.
Good video
Michael Cuffee
Thanks for watching.
@@FabRaceModRepeat not a problem,very useful cause im getting into racing myself.
Michael Cuffee
Glad to hear it!
It’s a great and fun sport.
gudgeon pin
What is another name for wrist pin?
Looks like a stroker piston
Kevin Humphrey
Yes indeed.
347, customer ended up going big block instead.
It's spelt groove not grove
The occasional fat finger happens, it’s been out there this long. It’ll be ok
Thanks for watching