69 Upper Control Arm Staft Fastner Issues

[Michael C.]

When trying to torque the bolt on the inboard bushing on the left side upper control arm the split/lock washer keeps spreading or breaking before I reach the torque value (40'#). The washers are supposed to be grade 8. After the second washer spread open, I examined the underside of the bolt head (new bolt). It did have a burr that I thought might be causing this issue. I smoothed it out with my Dremel, but the third washer did the same thing. No problem on the right side of the car. In the attached photo you can see that the retainer has become scored. I've smoothed it out between failures. Suggestions?

While on the topic of upper control arms - how is someone supposed to torque the forward bolts? There is very little clearance between the bolt heads and the radiator surround. I can manage to get a flexible ratchet wrench on the bolts to get them snug, but the limited room doesn't allow me to really "torque" them. Currently the upper radiator hose is out as is the alternator and master cylinder on the left and A/C hoses on the right. I've read many suggest periodically checking these bolts, but how is that doable once everything is in place?

On the topic of split/lock washers - I read comments on engineering forums that claim that these washers are no better than flat washers once compressed. Obviously, GM and other manufacturers of various types of machinery disagree because they keep using these washers.

Thanks
Mike
ControlArmShaftWashers.jpg

[Mark E.]

Re: 69 Upper Control Arm Staft Fastner Issues

My initial thought is a bad batch or counterfeit sourcing of washers. I wouldn't think grade 8 material would fail with 40 ftlbs. So try another source for washers and make sure they are the proper outside diameter.

Use a torque wrench for the rear bolts. Then apply a box end wrench to those bolts to get a feel for their tightness. Using the same wrench tighten the front bolts by feel.

[Richard M.]

Re: 69 Upper Control Arm Staft Fastner Issues

Mike make sure you use Blue Loctite too.

[Richard K.]

Re: 69 Upper Control Arm Staft Fastner Issues

Michael, I too have the problem of getting a wrench around the front control arm bolts due to clearance issues.
I'm going to try a "double flexible flare nut wrench". Found one at Carnagetools.com Might want to take a look. Hope this helps.

[Gary S.]

Re: 69 Upper Control Arm Staft Fastner Issues

I questioned this forum a year or so ago about how to get in the tight spaces between the radiator hose and core support. I found a flex head ratcheting wrench from one of those "el cheapo" tool companies and it has worked well.

[Patrick H.]

Re: 69 Upper Control Arm Staft Fastner Issues

If you're re-using original washers, that may be part of it. I think they're just old and fatigued.
I had the same thing occurring, so bought a batch of new Grade 8 lock washers, stripped them and then black phosphated them. No more breaking.

[Michael C.]

Re: 69 Upper Control Arm Staft Fastner Issues

These double flex wrenches do look interesting. Let us know how it works for you.

[Michael C.]