CV bolts.

Stan Gillis · 03-04-2011, 08:57 AM

Any advise on securing the CV bolts in place?

pete3799 · pete3799's Garage

You mean besides torquing them?
Here's all you need to know about CV's
Reconstructing Constant Velocity (CV) Joints

jcsjcs · jcsjcs's Garage

Definitely read the link provided.

AND re-torque after 100 miles.

Make sure you that your hex wrench is solidly in place as you tighten - as you don't want to strip the heads.

I found that it was really easy to tighten the bolts with the rear wheels off and a screwdriver in the rotor to keep the axle from turning.

BK911 · BK911's Garage

Quote:

Originally Posted by jcsjcs

I found that it was really easy to tighten the bolts with the rear wheels off and a screwdriver in the rotor to keep the axle from turning.

Genius. Wish I had thought of that before. But at least I know it now!

gtc · gtc's Garage

Use schnoor or nordlock washers. Available from fastenal.

gsmith660 · 03-04-2011, 01:05 PM

Stage8 locking CV bolts

25% off Stage8 locking CV bolts - Rennlist Discussion Forums
I think this group buy is done and he is not allowed to post this on this forum for some reason

911pcars · 03-04-2011, 02:22 PM

Read the lengthy thread on safety wiring Weber venturi lock screws.

Sherwood

snbush67 · snbush67's Garage

Quote:

Originally Posted by gsmith660

Stage8 locking CV bolts

25% off Stage8 locking CV bolts - Rennlist Discussion Forums
I think this group buy is done and he is not allowed to post this on this forum for some reason

+1 on the Stage8 easy to install, and great peace of mind.

Shane

Stan Gillis · 03-07-2011, 04:52 AM

What size CV bolts, diameter and length do I order to fit a 73 911T, using the Schoor washers?

What size Schnoor washers are used for the CV bolts?

Stan

JeremyD · JeremyD's Garage

I did the system 8 - especially with only 8 bolts per axle

cbush · 03-07-2011, 05:46 AM

I know this is contrary to most advice on here, but I use both the old bolts and washers. They are not stretch bolts, and the washers are not crush washers. Simply torque them as stated, and check the when you service the vehicle. I have been doing this for 25 years now and NEVER had any problem with three different cars. Does the factory manual say replace the bolts and washers? If it does I must have missed it. Perhaps the newer cars are different than the pre-1980 models.

RoninLB · 03-07-2011, 06:17 AM

i believe porsche text is that the CV bolts can be used 3x.. which i don't understand why this is so

hcoles · 03-07-2011, 06:37 AM

I made sure the threads and mating faces were clean, added never seize and torqued per spec. , haven't had an issue. I've also put a paint mark on the bolt head running down to the cv material so I can look and see if the bolts are moving, probably would not catch in time, but it was an idea.

RWebb · RWebb's Garage

I've never heard of a 3x usage limit on the bolts - inspect them (threads AND wrenching fixture) as per an old post by Fastenologist Jim Sims and reuse.

I HAVE heard of people reusing Schnorr washers 2 or 3 times and getting away with it. But, as I posted on a thread just the other day, be safe and toss these things into the metal recycling bin each time. They are small and inexpensive, so why even bother keeping records on their past life??

Porboynz · Porboynz's Garage

I have a broken CV bolt in my collection of offerings to the 'Gods of Speed' on my garage wall. The bolt was walking out of the outer CV and heading for mischief when I just happened to spot it while bleeding the brakes. For the cost, a new set of grade 8 capscrews/bolts and Schnorr washers seems cheap to me. Those Stage8 locking bolts look very cool, never seen them on this side of the Pacific Ocean.

Walt Fricke · 03-07-2011, 10:22 PM

I'm going to have to look into the Stage 8s. I didn't know that stuff was available in metric sizes.

But like Chuck I just reuse my stuff and have never had a problem. I've tossed bolts when the inhex got buggered. But now I use 12 point cap screws and like that a lot better.

While some may say that for a race car you can't afford not to use new bolts, I have the opposite view for my amateur efforts: I am pulling the transmission often enough that new bolts would be more annual expense than I can justify given my lack of problems.

For a street car with five or ten year intervals between removing any of these bolts, just buying new ones makes more sense.

On the other hand, supposedly fasteners are designed (as part of a structure) to be used only a certain number of times to retain their full strength, I think. There is some amount of wear (more if not lubricated?) with each time they are fastened and unfastened. That might be part of any "use 3 times" notion. Makes some sense, but at what point is this wear significant enough to lead to failure?

RoninLB · 03-08-2011, 12:15 AM

I couldn't find the hard info about 3x

I checked early Workshop Manuals and most of Up-Fixin. Haven't checked BA Tech Manuals yet.

From Stoddard to Alan Caldwell, to Grady Clay, to Bruce Anderson is one sweet read.

lin7310948 · 03-08-2011, 07:04 AM

i was also trying to decide what to do about the bolts...so i just ordered the grade 8 set from Ideola for my 78 930...

Trackrash · Trackrash's Garage

I'm wondering if the type of CV would have anything to do with it.

Do the older 4 bolt CVs have less of a problem with their bolts coming loose compared to the newer 6 bolt CVs?

Jdub · 03-08-2011, 11:00 AM

For the philisophical question of Why new? I'd say it is for the peace of mind. Seeing what happens to cars where the shaft let go is sobering. My personal experience catching several stipped bolts and helicoiling of the trans flange is doc'd on this site.

Good tip is to always use a fresh, hardened hex or multi-point when removing questionable sockethead bolts - cheaper than stripping out the fit with a lesser (used) tool.