SPF Rear Wheel Bearing Replacement

[Neil]

Hello all,

Bringing up an old thread...

Anybody out there who did the "donkey work" described by Jac Mac regarging finding shims matching the spindles?

So far I got away with frequent adjustment of wheel bearings but getting tired of this and looking into making a sleeve + (buying) shims to extend TBO.

On a separate topic, today I wenn through "all (?)" of the SPF wheel bearing threads and found all kind of information about what to do and the discussion about the Design flaw except a consistend description of the "preload" during bearing adjustment.

1. Some (most) talk about preload the bearing (which in my understanding would be fully tighten the nut and then add some "torque" to "preload" the bearing)
2. others describe to fully tighten the nut and then turn the nut counterclock wise to give "air" into the bearing

So far I used method # 2. - I turned counterclockwise about two holes from of the adjustent nut.....

Any comments?

Thanks in advance
Markus

Markus;

When we ran an M8C in Can-Am in '72 & '73, we adjusted the pre-load on the wheel bearings as follows:

1. Tighten the wheel retaining nut lightly finger tight.
2. Spin the wheel/tire by hand rapidly.
3. With a socket wrench, tighten the nut until you feel the rotation begin to slow.
4. Back off to the next lock notch.

Simple.

 

[Markus]

Hello Dave, Hello Neil,

Thanks for your replies.

@Dave, I usually check the spindles when repacking the bearings - so far they seem to be "OK".

Regards from a sunny day in Germany - driving season is coming closer....

 

[Richard]

Markus thanks for the info for setting the bearing preload. Now that I have lathe and a surface grinder I can make my own spacers. However my question is how would you measure the space between the inner bearing races? I guess you could make something that you know would be to long, put it together and use a dial indicator to measure the movement of the outer bearing race to get a bit closer. Then shave a little at a time until you get it right, hoping you don't take to much. I think you would have to start from scratch on the other side.

Maybe if you could find shims the right size that would be the way to go.

I know how much torque it took to put the splines together has nothing to do with bearing preload I just thought it was strange it took some much to take it apart or back together. I broke the first The parts are hardened, files wouldn't touch them. I even tried some small stones but didn't have the 2 or 3 days it would have taken to fix the problem.

 

[Skip Markley]

I made the spacers about 1/8'' longer than necessary. Assembled the wheel and tightened the nut tight. Measured the endplay (because the spacers were too long), disassembled and faced the spacer by about 50% of the endplay. Repeat. Repeat. Repeat. Repeat. Repeat. Finally was able to achieve the perfect amount of play (just a tiny rock of the wheel when tight) and no issues. Each spacer was different on each wheel. Remember, if you face too much off then you get the pleasure of starting over. I also chrome plated and ground my spindles on all 4 corners. They were too loose from the SPF Factory. Here are the final diameters I specified after grinding: Large bearing diameter 2.0000'' (+/- 0.0003''), small bearing diameter 1.8120'' (+/- 0.0003'').

 

[Dave Hood]

After having to adjust or replace my bearings every 8-12 months over the course of several years, Holman Moody measured and installed spacers back in 2014. The bearings have been fine since then although I've driven more than 21,000 miles. Unfortunately, these have to be manufactured based on the dimensions of each hub and can't be mass produced for all SPF cars. I don't know if Superformance has updated this design, but this is one of their biggest design flaws where a more modern approach could have been taken.

 

[Richard]

Do you have the length of your spacers? That would at least give us a starting point. I may also start with some PVC pipe.

 

[Ryan L]

I wonder could you get a bunch of shims laser cut out of some thin material and then use a nominal spacer and shim accordingly.
you could even get the shims cut from 2 different thicknesses, that would give you the difference in between them as an adjustment amount.
once a known number of spacers was accounted for you could then get a single solid piece made up to the measured length.

Only need enough spacers to do one corner at a time from a measurement perspective. Just time consuming to pull it all apart multiple times..

 

[Randy V]

I’m somewhat surprised that they don’t set these up with a “crush” spacer/sleeve like those commonly used on pinion gears in differentials…
Two different ones shown here

 

[Markus]

Hello all,
Thanks again for your contribution on this matter .

@RICHARD, I also thougt about how get an initial length for the sleeve > when looking to the picture Dave Hood posted above in #25 the following comes to my mind:
1 Jack up desired corner
2 remove locking Ring and clean everything
3 adjust wheelbearing to proper/ desired clearance
4 measure the length from end of spindle to looking nut - Note result
5 with the spindle still in the car and a helper pushing / holding the entire spindle / wheel setup in position
6 remove the innside wheel bearing (rollers) and then measure the dimension from ouside bearing "inner" race at the spindle to end of spindle - Note result (total outstanding lenght of spindle)
7 measure thickness of inner bearing + Nilo sealing ring + thickness of looking nut - Note result
8 take measurement result of 6 - result of 4 - result of 7 = approx. length of needed sleeve
9 maybe add some amount to stay on the safe side....

Sorry for the lengthy description

@Skip Markley, your method also seems to be a good way to get the sleeve to proper length- thanks

@ Dave Hood, thanks for confirmation of sleeve solution - sounds promising

@ Ryan L, this was also sugested by Jac Mac in post #12 > https://www.gt40s.com/threads/spf-rear-wheel-bearing-replacement.48951/post-498160
Now it would be great to find matching shims from another application and incorporate this into the Design of the sleeve.....?? Anybody??

@ Randy V, yes, somebody brought up the crash spacer idea before (I think it was you!?), unfortunately here in Germany it would tough or impossible to find crash spacers as the variety of possible matches seem to be very limited.... however, this solution would allow for some room for error in sleeve length?

Looking forward for continued discussion...

Markus

 

[Skip Markley]

My blank spacers were 2-1/2'' long. I then faced them per my earlier post.

 

[Brian Kissel]

Hello Markus. If it would help for setup, McMaster Carr offers shims with a 2.000 diameter inner hole. They come in individual sizes .001-.010, .012, .015, .020, .025, .030, .048, .062, .090, and .125. They also offer a kit with one each of the above sizes. You could come up with a starter spacer and add shims to get the perfect setting and then take that dimension to make a solid spacer. If there is a issue with them not selling into Germany, I would be more than willing to order for you and send them to you . If this is something you are interested in, please PM me and we can work out the details.
Regards Brian

 

[Markus]

Hello Brian,
Thanks for the offer, I will check McMasters website... and contact you.
When I tried to order from them, some time back, they did not sell to Germany.

Regards,
Markus

 

[Brian Kissel]

Markus, happy to help out anyway I can. I just noticed the individuals I have listed are stainless steel but are available in 1010 steel also.

 

[Markus]

Brian,

...... wow, what a service - thank you very much.
I love this forum.... or better the people which make this forum possible. Not to forget Ron and the Moderators etc.

Looking to your screenshots and McMaster website and the minimum order quantities of 5 / 10 I might as well opt for the 19 piece carbon steel ring shim set you also posted:

McMaster-Carr

McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day.

www.mcmaster.com

I will further investigate on the weekend and send you a PM.

Regards
Markus

 

[Dave Hood]

Do you have the length of your spacers? That would at least give us a starting point. I may also start with some PVC pipe.

Richard, I'm afraid I don't have the length of my spacers. They were manufactured by Holman Moody in their shop.

 

[Richard]

Thanks Dave I'm hoping I never have to redo the bearings again but I'm much better prepared if that day comes. I think I'd crumple up some aluminum foil and stuff in the space between bearings to get an starting point.

 

[Markus]

Hello all,

Another question on that topic.

Are there any recomendations on bearing manufacurers as pricing spreads all over the place?

E.g. 18690/18620
No name from 25€
NTN 32€
Timken 44€
SKF 110€

Not looking into buying cheap (and twice) but are SKF bearing that much better over Timken to justify 2.5 x the price?

Considering similar pricing for the 18790/18720 bearing a complete set (4 inner + 4 outer bearing) would range from 352€ to 880€...

Any input/ experience?

Thanks,
Markus

 

[Dave Hood]

I've only used Timken.

 

[Brian Kissel]

I agree with Dave. Use Timken. Do it once, do it right.

Regards Brian