Reconstructing Constant Velocity (CV) Joints

[proffighter]

Originally Posted by winders

In the 930 CV joint application, the M10 bolts torqued to 61 ft-lbs don't need any type of lock washer. The clamping force is sufficient to prevent loosening.

My race car uses 930 CV joints with the M10 bolts with no washers. I check the torque of the M10 bolts before every event and they have never been loose.

The M8 bolts use on other Porsche CV joints, torqued to 34 ft-lbs, are a different ball game. They need some help to prevent them from loosening.

Scott

Yep

[JJ 911SC]

Originally Posted by Discseven

Nick,

I believe the CV on the left is installed backwards. My understanding is the the groove in the CV should always be towards the end of the shaft.

Someone check me on this please.

Well, just like Nickshu, I end up receiving 3 Lobro axles via PP (outstanding customer service).

All with the same part number (all packed loose from Lobro in oversizes grease soil broken boxes)...

* 2 with cork flanges and 1 machine flush flanges.

* 2 with 30mm flanges and 1 with a 33mm flanges (one of the corked one) so I still have different axles as there were no possible matched. God knows how many axles do one need to have a match?

* 1 with no grove on both flanges

* 1 with 3 groves away from the axle side on one flange and 1 grove on the axle side on the other flange

* 1 with 1 grove on the axle side on both flanges.







Also on this pic with the 2 axles side by side, the contracted and extended length (shown) are different...



Lobro packaging expertise;




The one wrap in the plastic bag his my return (the machined flush one) to PP.

[Nickshu]

Yep, use the cork ones, Loebro told me both will work but the cork are higher quality units.

[jrsully]

Just picked up on this thread, Have a low mileage (53k) 71 Targa , the axels have nice boots, no issues. What is recommended for a rebuild if necessary.? Thx in advance JS

[ClickClickBoom]

TRT, just because its needed!

[safe]

A nice upgrade would be an end cap to make it less messy to install and remove drive shafts.
Has anyone seen one that fits?

[ClickClickBoom]

Once agai BTTT.

[Ferrino]

I was wondering if I could tap into the expertise on this thread and invite suggestions on my rather unique output flanges. They are 108mm flanges from a 1984 turbo look tranny. However, they are installed in a non-turbo 911 which has 100mm stub axles and so whoever dropped this tranny into the chassis decided to have the M6 holes drilled and tapped into the flange to accept 100mm CVs (rather than just swapping for a 100mm flange).

Anyhow, I am now about to buy new axles (CVs are shot) and am contemplating upgrading to the 108mm 85-89 Carrera axle (with integral stub axle). Does anyone see a major problem in milling off the 1mm outer ridge of my flanges, so as to create a flat mating surface for the 108mm CV joints (which don't use gaskets)? I appreciate that there will be 1mm less depth of M10 thread and that the grease caps on the late Carrera axles might not fit.

Or do you think I should just sell these 108mm flanges and find some 100mm flanges and stick with 100mm axles? I would like to turn the car into a dual-purpose street/track machine.

Here's a pic of the flanges:

[sc_rufctr]

I would sell the108mm flanges (if you can) and buy some 100mm flanges.

[Ferrino]

Originally Posted by sc_rufctr

I would sell the108mm flanges (if you can) and buy some 100mm flanges.

If I was to source 100mm flanges, how many variations are there for the 915 transmission - is it just "coarse" and "fine" splined versions? I have a ZF LSD in my tranny - does that make any difference when matching the splines? Thanks.

[Ayles]

Good reading here!

Finished removing mine tonight. CVs are shot and I will be ordering new and would like to put it back together in the strongest manner possible.

Is there anything else I need to consider other than the addition of the moon plates and scnorr washers. My engine is 279hp on the dyno(never been in the roller I have) and I know that's pushing it for some of the stock drivetrain hardware.

[euro911sc]

If you are replacing all the CVs then send the axles out to be blasted and powder coated. Its cheap, but provides a great coating for a healthy long life. Also, get yourself all new bolts. If you do not plan on removing your engine a lot buy them here. If you remove your engine a lot like I do I just buy a box of 100 at msc or grainger. I use them twice then toss them in my used HW bin.

Oh yeah, when you re-install them (cap-less ones) take some RTV (very small amount) and smear it at the joints between the CV/axle plate/out-put flanges. Keeps your CV grease in those cork seals are useless...

[mtbguy]

Hey guys- thanks for all the info on this thread so far. I replaced one of mine last night on my 1987 Carrera (bought a complete new axle assembly from pelican). I torqued bolts to correct 60/61 ft pound values. Plan on rebuilding the old one to use on other side or keep as spare.

Today I test drove car about 5 miles and all seemed fine until I got back onto my street. I cornered abruptly onto our street due to oncoming traffic that changed lanes without warning and looked like he might hit me.

When I pulled into garage it seemed like the axle was dragging/heavy or had a slight wobble. Once it cools off plan on re-checking torque, or do the joints sometimes need to "loosen up" a bit and get more flexible with a few more miles? Or maybe a brake pad is dragging on that side?

Thanks!

Rick

[Dodge Man]

Originally Posted by jrsully

Just picked up on this thread, Have a low mileage (53k) 71 Targa , the axels have nice boots, no issues. What is recommended for a rebuild if necessary.? Thx in advance JS

The replacement Lobros are just 84-87 Carrera axles with 2 roll pins in each CV. Axel OD is much better than early 70's for you big motor converts too!!! Keep your OEM units in a plastic bag and get the new Lobros from PP. The complete axel units are less than a single early CV. McMaster has the new 12.9 M10 bolts & Schnorr washers(follow install instructions on washer orientation) to protect your investment. PP has new 1/2 moons & the gaskets too.

[Dodge Man]

Originally Posted by safe

A nice upgrade would be an end cap to make it less messy to install and remove drive shafts.
Has anyone seen one that fits?

The 84-87 Carrera tin caps should work on the 108mm. I did not try it with the early roll pins. With the later trans & stub axle flanges it should be a go. The early gaskets are a huge pain in the posterior. Lots of profanity that day with the Euro trans cooler pump in the way.

[ClickClickBoom]

TTT just because!

[christiandk]

If you have the ones with the fat flanges and the rubber is not completely cracked..............Use the hours and kilometres of paper towel to restore it! And after it is clean use glycerine.

On my old cars I threw the old boots out because it IS messy to restore....but well worth it. The new ones are trash compared to the originals.

[ClickClickBoom]

This should be a sticky!

[jcsjcs]

Or at the very least gooey since it is such a messy job.

I did this one last year - and was having flashbacks at Hershey Swap Meet over the week as I saw all the CV joints lying around.

[Hendog]

Originally Posted by christiandk

If you have the ones with the fat flanges and the rubber is not completely cracked..............Use the hours and kilometres of paper towel to restore it! And after it is clean use glycerine.

On my old cars I threw the old boots out because it IS messy to restore....but well worth it. The new ones are trash compared to the originals.

I too re-used the old boots. My old boots were still in excellent condition. I found the new ones were NOT as pliable as the old ones; I have them stashed away in my parts bin.