Bell housing run out

[Steve L.]

How many of you check runnout when changing bell housings?

[Domenic T.]

Re: Bell housing run out

Steve,
You must mean the 2 line up pins and bearing retainer opening. never saw them wear but saw the wrong sized bearing retainer hole such as using a 63 munci in a later bell housing.

Dom

[Steve L.]

Re: Bell housing run out

I mean checking the runout between the crank and the large bellhousing pilot hole that the tranny locates onto. This is done by placing a magnetic mount on the crank with a dial gauge following the bellhousing pilot hole. Any misalignment over 0.010 is adjusted by getting off center alignment pins.

Doing this looks like a PITA proceedure.

[Domenic T.]

Re: Bell housing run out

Steve,
Now I'm on the same page. I doubt that that is done much, most trust the factory there. Good idea but the fix would not be easy.

Dom

[Domenic T.]

Re: Bell housing run out

Steve,
Misunderstood the pin thing. Did you mean there are pins available or is that something that has to be machined?

Dom

[Michael C.]

Re: Bell housing run out

My experience is that most factory bell housings are within spec. Aftermarket housing are another story. They all should be checked while you are doing the trans. R&R anyway.

Mike C.

[Edward B.]

Re: Bell housing run out

A lot of bell housings aren't in tolerance. Read THIS for more info.

Ed

[Steve L.]

Re: Bell housing run out

Steve,
Misunderstood the pin thing. Did you mean there are pins available or is that something that has to be machined?

Dom

Check Edwards link.

[Paul D.]

Re: Bell housing run out

The old 3spd and 4spd transmissions using the oiled bronze bushings seem much more forgiving to any SLIGHT alignment issues when changing or R&R of bellhousings. The problem seems to be critical when running the newer 5 and 6 speeds, which usually dictate the use of a needle bearing pilot to replace the old oiled bronze bushings. I've read of some cases of premature failure of the needle bearing type bushings when used with older 4 speeds. Probably due to alignment issues also. Maybe the needle bearing bushing is what is so critical for alignment more so than transmission type. Can anyone offer why the needle bearing is preferable over the bronze bushing (other than the obvious less friction notion)?
Chip

[Domenic T.]

Re: Bell housing run out

Paul,
IMO the bronze is WAY better than a needle, because it has WAY more contact with the shaft. Needles are good with RPM's, but everything is spinning at the same RPM with the clutch out. Some shafts are not hardened to be the inner race of a needle bearing set up, especially with the minimal contact of each needle.
Needle bearings also need good lubrication where the impregnated bronze can work even when the lube is gone.
I'm referring to the older input shafts.

Dom