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Elliot Cannon
I guess this goes under the "for what it's worth" collumn but I recently bolted up my inner CV joints. I used gaskets and torqued them down. I waited till the next day to safety wire them and decided to re-torque them. Each bolt turned an additional 1/8 to 1/4 turn. Some of you might already use this tightening technique but I thought I'd post it anyway. For what it's worth. biggrin.gif
ConeDodger
Good to know!
reharvey
After driving mine about a 100 miles I retorque them and they almost always turn another 1/4 turn. Don't know why but that's the way it has worked out for me.
Elliot Cannon
QUOTE(reharvey @ Mar 16 2013, 04:47 PM) *

After driving mine about a 100 miles I retorque them and they almost always turn another 1/4 turn. Don't know why but that's the way it has worked out for me.

I think it's because the gaskets compress.
Dr Evil
I stopped using gaskets as there is no way to accurately tq the bolts with a compressible substance in the mix.
bandjoey
The dumb question of the day then...
Why did the factory give a torque setting with a gasket?? Did they intend for you to re-torque after a break in period?
confused24.gif
Do U use the same torque without the gasket?


Thanks for the info.
Elliot Cannon
QUOTE(Dr Evil @ Mar 16 2013, 08:07 PM) *

I stopped using gaskets as there is no way to accurately tq the bolts with a compressible substance in the mix.

So you can never accurately torque a bolt that compresses a gasket? happy11.gif poke.gif
reharvey
popcorn[1].gif Here we go
pcar916
QUOTE(Elliot Cannon @ Mar 17 2013, 01:43 AM) *

So you can never accurately torque a bolt that compresses a gasket? happy11.gif poke.gif


You can but it'll change. beerchug.gif

I stopped using gaskets... forever ago. With a gasket, if the CV compresses the gasket enough for solid metal to metal contact no problems. But I believe that those particular gaskets (which is very stiff) hold the cv apart from the flange. In that case there will always be a correction later. Frankly a silicon O-ring would be better in this application than the gaskets we use.

Long ago I would over-torque by two-three pounds to avoid the gasket compression problem until converting to high-temp silicon instead. Without the gasket, installation is slightly more difficult (on the car) because keeping the contact surfaces free of grease is sometimes tough. The CV floats in and out and occasionally pushes grease out while fitting it to the flange. Then you have to start over to clean the surfaces again (with acetone/lacquer-thinner/MEK/enamel-reducer, or your other favorite petroleum solvent) or it'll leak.

CV's that have all bolts are IMHO easier than those with roll-pins since they can fit up to the flange without having to push the CV so far back.

An added measure of sealing can be had with some aluminum tape around the CV/flange joint. It's a pain to remove but so is slung CV grease.
r_towle
QUOTE(Elliot Cannon @ Mar 17 2013, 03:43 AM) *

QUOTE(Dr Evil @ Mar 16 2013, 08:07 PM) *

I stopped using gaskets as there is no way to accurately tq the bolts with a compressible substance in the mix.

So you can never accurately torque a bolt that compresses a gasket? happy11.gif poke.gif

Made me scratch my head also considering the wide industry use of Head Gaskets and other gaskets that can be torqued to spec.

Double torquing is also industry standard from what I have found.
Even with stretch bolts the directions I have read (yes I read the directions sometimes) say to run the engine for a period of time, then re-torque the heads.

I also re-torque the heads on a type 4 motor...with no head gasket.
They also need to be done once the motor is broken in.

rich
Dr Evil
*Such a compressible material. Jeez guys, anal much?

The paper gaskets in the CV are far from the rigidity of the head gaskets or other paper gaskets used elsewhere. They are spongy. 30ft/lb aint much tq and it loosens up pretty fast as shown here.
r_towle
I am now curious as to what the factory trained guys like the Cap'n and Woody are told to do, and do on a regular basis every day.

Also, did the CV joint gasket appear on every year 914?

There must be some engineering and documentation behind these gaskets?

Seems like gaskets are used in this application on quite a few cars nowadays, with no major issues.

I would assume (not being an engineer, nor a factory trained mechanic) that the gasket not only provides the function of keeping the grease in the CV joint, but also applying reverse pressure against the threads of the bolt to HELP keep them from coming loose.

It seems to me that the gasket would server two purposes.

I have personally never had an issue when I used the gasket...but always have issues when I dont use the gasket.

I followed the advise learned here and had one axle get loose and fall off.
I went back to the gasket (torqued twice) and have never had them loosen up again.

Not sure what the issue really is, but it seems to work.
Maybe I have been lucky.

I will admint that ever since I lost one axle, I check the bolts at least once per year...and everytime before and after an autox.

That is standard nut/bolt for an autox though.

Since using gaskets (again) I have never found them loose.

Rich
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