The Stovebolt Site Forums The Shop Area Driveline Clutch pilot bushing vs roller bearing

I'm getting ready to transplant a recently rebuilt 235 into my 49 3/4 ton. It'll be bolted up to the original truck flywheel, bellhousing and granny gear 4 speed. The donor motor came from a 1957 210 series car with a manual 3 speed. I'm pretty sure that motor originally came with a bronze pilot bushing in the end of the crank but it now has a roller bearing.

I'll be replacing the old bearing before the transplant. My question, is there any advantage to replacing it with another roller bearing, or should I go back in with a bushing?


Thanks in advance,
Steve

Using a needle bearing in that application is like putting lipstick on a pig- - - - -there's no real reason to do it, and the result might have some real downsides. There are too many moving parts that can fail in a roller bearing setup, so I can't imagine any good reason to substitute it for the old reliable oilite bushing that has worked for decades in untold millions of vehicles.
Jerry

Bushing less likely to damage imput shaft v.s. bearing if it fails.

Why some applications use a ball/roller bearing, and others use a bushing is something I have wondered about for along time.

Awhile back, I bumped into a retired driveline engineer, so I asked him that question. He said that some engineers would specify a bearing, if it was anticipated that the vehicle might be used in situations that required the clutch to be disengaged for extended periods of time. He did not elaborate of any specific applications and I kind of got the feeling that the choice was more subjective, than driven by any hard data.

I have also read that some transmissions need a more precise alignment of the input shaft, requiring a bearing. But that is just internet chatter, and I have no personal experience along those lines.

I am in the bushing camp. I have seen a number of input shafts damaged by bearings. None by bushings.

Edit: Actually, just happen to have transmission in my garage now, with a damaged input shaft...

Take a pass on the roller bearing. They are generally harder then the input shaft and will always cause damage. Use a real oilite bronze bushing, not a cheap bronze version, but the real deal impregnated bushing.

https://www.stovebolt.com/ubbthreads/ubbthreads.php?ubb=showflat&Number=988781

On my 39 216 it uses a roller bearing. The diameter hole in the back of the crank is larger than a bronze bushing diameter. Do any of you know of a manufacturer of a larger diameter bushing?

Rick

Like Dragsix says, buy the good bronze bushing, NOT the one that a magnet will stick to.

Rick, drop me a PM- - - - -I can either make you a bushing from a piece of oilite round stock, or a reducer sleeve to make a standard bushing fit your crankshaft. All I need is an accurate measurement of the trans snout and the hole in the crankshaft.
Jerry

Isn’t there 2 different sizes?

What years?
0.649 bearing 1939-1957 (or to 1966 or 1987 in some applications), except Powerglide.

Did the Powerglide engine/crankshaft have no busing bearing?
I recall seeing vendors sell such a bearing for Powerglide 235 engines later used with a manual transmission (I'll post a link, if/when I find it - Dorman 690-034).

The early 216's used a roller bearing instead of a bronze bushing, and the counterbore in the crankshaft is an oddball size. Rick would either need a custom made bushing or an adapter sleeve to reduce the crank counterbore enough to accept either one of the readily available bushings sold by most vendors.
Jerry

What year 216 Stovebolt engine had a standard roller bearing?

I believe it was 1937-40 or somewhere in that range.
Jerry

1937 to early 1939 used a ball bearing.
Late 1939-46 used a roller bearing, but it has the same dimensions as the oilite bushing, so most have been replaced with that by now.

Thanks, Dave

31-39 for the bearing?
33-46 for the retainer?

1929-1957 parts manual
also listed here - 1929-1941

Did GMC 6’s use a bearing or bushing?

My 49 gmc 228 has the bronze bushing. John

The military 270s used a ball bearing. (PN: 907109)

Best Regards..

Thanks, Bob

[img]https://www.oldsobsolete.com/produc...nkshaft-clutch-pilot-bearing-nos-907109/[/img]

It looks like that bushing/bearing (New Departure # 7109) could/can be used on many vehicles (up through about 1956 - up to 47 for GMC/Chevrolet)?

The one in my truck looked just like that. It was an NDH.

Timken, SKF and others offer the same bearing - although they are not made in the US.

Not sure how accurate it is, but if you pull up the "applications" for these on a site like Rock Auto, you get hundreds of hits ranging from like 1936 Buicks to 1979 Pontiacs, with a few Internationals and Kaiser-Frazers thrown in as well.

However, wonder if this means this bearing was originally used in all of these vehicles, or rather could have been used originally, or as a replacement for the bushing?

Best Regards...

That 7109 bearing was only used up to early 1939.
It has a much larger OD than the bushing.

1931 to early 1939 used the 7109 ball bearing (1.379"OD x .593" ID).

Late 1939-46 used a roller bearing(GM part #142655, Hyatt#99004).

The retainer (GM #836713) was only used with the roller bearing.

(This roller bearing/retainer setup was also used on 1933-34 Standard, but this is a truck forum).