Bairs rebuilt rear spindles seem too stiff ???

[Michael H.]

I know you're hoping I'll respond to this ...

....childish nonsense but I won't.

[Duke W.]

Re: Bairs rebuilt rear spindles seem too stiff ???

There's no doubt that when you set the clearance at a thou or less, measurement of actual clearance becomes problematic, and it is as much art as science.

Back in the eighties, Mercedes recommended an initial inspection in the range of 1000-1300 miles, and it was a complimentary service. In addition to an engine oil change and fluids check the inspection called for a measurment and correction, if necessary, of front wheel bearing clearance. That possibly illustrates the difficulty of getting the four to eight tenths at the factory, or maybe there was a tenth or two of "run-in" that they were concerned about.

I believe I set my '63 Corvette's rear spindle pack at three to four thou (I would go tighter today by filing shims as necessary to get one to two.), but I can't remember if I remeasured after the final assembly with grease. I do recall that my first set up was "dry" in order to get the most accurate measurement.

So back to Joe Randolph's issue. I still recommend that he "run in" the bearings on the bench, then measure or check for end play feel. Given that Bairs has a good reputation, maybe he should go ahead with suspension assembly, but after a few hundred miles he should check again by jacking up the rear, grabbing the top and bottom of the tire and wiggling it. I still believe just a hint of clearance should be felt.

Duke

[Tom Dooley]

Re: tom,is ralph johnson still at crane???

Hi Clem. Yes, he's still there. I talked to him last week. I haven't actually seen him for two years because I had to miss the last xmas party at Crane Cams but I talk to him often. I'm now on the west coast of Florida and he is on the east coast so I don't get there as often as I would like. He would know me as Tom Petitpren.

[Clem Z.]

he worked with some people i knew at GM

a long time ago.we had a mutual friend at GM,bill howell,who told me to look ralph up when i was in fla. i have not seen him for 4/5 years and he most likely does not remember me by name. ralph is a very interesting fellow.

[Tom Dooley]

Re: he worked with some people i knew at GM

I just tried to call Ralph on his private line but he wasnt there. I don't remember bill howell but the name sure sounds familiar. mike h and I spent just about 2 hours on the phone with ral;ph a while back and covered everything from turnips to crankshafts to flying saucers. Hes great to chat with. I'll mention your name next time I talk to him.

[Joe L.]

Re: Bairs rebuilt rear spindles seem too stiff ???

Duke-----

Yes, I feel very confident that after the assembly is on the car and run several hundred miles and checked, qualitatively as you described or with a dial indicator, end clearance will be confirmed. Actually, the qualitative test is all that really will be needed unless no end play is still observed using it. I'm about 99% sure that won't happen. In fact, there's a good chance that with the wheel and tire mounted on the spindle, the end play will be noted without a single mile put on the spindles. The extra "leverage" might be all it takes.

[Joe R.]

Update: Bairs rebuilt spindles seem too stiff ???

Hello All:

Wayne Womble had suggested an alternate method for testing for end play, and I tried it today. As shown in the photo below, I placed the entire trailing arm in my arbor press with the spindle under pressure (about 2000 pounds). This has the effect of locking the spindle firmly in the press.

With the spindle locked in the press, I held the trailing arm by the bushing end and gently tried to move it up and down. I was pleased to find that there was a very distinct rocking motion with rigid stops at both ends of the travel.

I mounted my dial gage on the trailing arm near the spindle and measured the movement relative to the spindle. The dial gage registered a one mil change as I rocked the trailing arm up and down. This is not a direct measurement of axial movement and I haven't tried to work out how the geometry translates, but it was enough movement to satisy me that the bearings are not installed with a preload.

My heartfelt thanks to everyone who contributed to this discussion and helped me to resolve this problem. I feel much more comfortable now knowing that my spindle bearings are not set up with a preload.

The amount of end play that Bairs provided is certainly on the low end of the recommended range, but I think it is sufficient to prevent premature failure of the bearings, which was my original concern.