What CV's are these?

[GaryR]

The last ones I put on (78 SC) had clamps for the boots, looks like these boots are part of the assembly (crimped in). Waz up with that?



I had a boot disintegrate at my last race, nothing left but the crimped in part..

[GaryR]

No one? All I see FS here is a boot/cap assembly but the boot is held to the cap with an external clamp... Sure it would work but I like the idea of no clamps better, just not sure where they came from.. could they be original on this car (50K mile one owner)?

[GaryR]

Flange showing crimp and how boot was attached..

[Scott Douglas]

Those may be the originals like you say.
Here's a pic of what I just put in my '78. New axle assembly from our host.

[GaryR]

Hmmm, those CV's look substantially smaller diameter (width) than mine or is it the picture? I would buy the already made flanges/rubber for $11 as my flanges aren't made for clamping externally. Does Pelican sell the crimping tool also?

Thanks for the reply Scott..

[Scott Douglas]

Gary
Sorry, I just remembered, my car has an early trans in it. It was retrofitted with a four speed sporto from an early car back in '96, so the CV's would be different.
The one pictured does only take the 47mm long bolts.
Scott

[Danny_Ocean]

The flange you have cannot be repaired. The boot is pressed in. The flange and boots come together as a kit. You can use hose clamps or use special crimpers for the included clamps.

[Grady Clay]

Gary,

These should be 100 mm CV joints. Is that what they measure?
These are type 923 CV joints from the 1976 912E (2-liter, 4-cylinder) that Porsche (bean counters?) thought sufficient for the 911 (3-liter, 6-cylinder) and later found out they weren’t.
About ’86, Porsche went back to an improved version of the 108 mm CV joint used ’69-’75 (including 1600 cc ’69 912).



Can you clean this flange up a bit and post close-up images (all six, each in focus) of the deformation (red arrows) of the boot flange seating surface for the CV joint bolts.






This seems to be an extraordinarily good example for why the 2-hole ‘moon plate’ washers are necessary.
The ‘soft’ mild steel of the boot assembly (previously ‘boot cover tin’) won’t stand the pressure from the class 12.9 bolt torque to 33 ft-lbs.
The deformation under the head of the bolt releases tension on the fastener, reducing the clamping force.
In turn, this can allow the junction between the CV joint and the transmission axle flange to slip.
Eventually the bolts unscrew and the connection fails.

Here is an important thread on this subject:
Reconstructing Constant Velocity (CV) Joints
While long, it is important to study it.

Best,
Grady

[sc_rufctr]

Grady

I have similar CV joints and crimped boots on my car (78SC). And they look very similar with the bolt area deformed in the same way.

What would you replace the crimped boots with? Flange with recess and band on boots???

[sc_rufctr]

Our host has these (EMPI) 923-332-037-00-M84

[GaryR]

Originally Posted by Grady Clay

Gary,

These should be 100 mm CV joints. Is that what they measure?
These are type 923 CV joints from the 1976 912E (2-liter, 4-cylinder) that Porsche (bean counters?) thought sufficient for the 911 (3-liter, 6-cylinder) and later found out they weren’t.
About ’86, Porsche went back to an improved version of the 108 mm CV joint used ’69-’75 (including 1600 cc ’69 912).



Can you clean this flange up a bit and post close-up images (all six, each in focus) of the deformation (red arrows) of the boot flange seating surface for the CV joint bolts.






This seems to be an extraordinarily good example for why the 2-hole ‘moon plate’ washers are necessary.
The ‘soft’ mild steel of the boot assembly (previously ‘boot cover tin’) won’t stand the pressure from the class 12.9 bolt torque to 33 ft-lbs.
The deformation under the head of the bolt releases tension on the fastener, reducing the clamping force.
In turn, this can allow the junction between the CV joint and the transmission axle flange to slip.
Eventually the bolts unscrew and the connection fails.

Here is an important thread on this subject:
Reconstructing Constant Velocity (CV) Joints
While long, it is important to study it.

Best,
Grady

I'll wire brush them up and get a better shot(s) for you Grady. I disassembled the CV that lost the boot and cleaned it, there are wear spots where the balls run so I simply bought brand new axle assemblies of the latest type so I don't have to mess with these anymore. I'm amazed of their condition after 33 years, even though the car has less than 60K on it (last 10K on the track)... i'm pretty sure they are the original CV's.

[GaryR]

Funny thing is I just bought two new complete axle assemblies and the boots are the same type, crimped inside the caps! The axles are substantially stronger (larger diameter) also. They even came pre-greased! Now I just need to find a schnorr washer supplier (and figure out what size fits properly)... is this it?

DIAMETER: M 6
INSIDE DIAMETER: 6.4mm
OUTSIDE DIA.: 10mm
THICKNESS: 0.7mm

[Danny_Ocean]

Measure your bolts. M8 or M10 washers are what you need.

[KTL]

Your '78 axles are most likely M8. McMaster-Carr has the real deal Schnoor washers. Dunno about the moon plates. Couldn't find the M8 plates here in Pelican catalog so I got them from a VW dune buggy store online.

Make sure you have ample length CV screws when you add the moon plates.

And don't trust that grease that came in the new axles. Do yourself a favor and get a good quality grease in there like Valvoline synthetic, Redline CV-2 or whatever. The basic grease they use doesn't last and you'll shorten the life of your CV joints on account of it.

[Pazuzu]

Originally Posted by KTL

Your '78 axles are most likely M8. McMaster-Carr has the real deal Schnoor washers. Dunno about the moon plates. Couldn't find the M8 plates here in Pelican catalog so I got them from a VW dune buggy store online.
.

Badda boom...
Amazon.com: OES Genuine Retaining Plate for select Porsche 911/928 models: Automotive

Dunno how I found them, but I did...

[Danny_Ocean]

Originally Posted by Pazuzu

Amazon.com: OES Genuine Retaining Plate for select Porsche 911/928 models: Automotive

$13.47 ea.?

They're about $2.99 ea. at your local VW supply joint (you'll need 12). And you'll need 50mm ~ 55mm bolts depending on the size of the flange/CV combo.

[GaryR]

Originally Posted by KTL

Your '78 axles are most likely M8. McMaster-Carr has the real deal Schnoor washers. Dunno about the moon plates. Couldn't find the M8 plates here in Pelican catalog so I got them from a VW dune buggy store online.

Make sure you have ample length CV screws when you add the moon plates.

And don't trust that grease that came in the new axles. Do yourself a favor and get a good quality grease in there like Valvoline synthetic, Redline CV-2 or whatever. The basic grease they use doesn't last and you'll shorten the life of your CV joints on account of it.

Thanks, I'm just running a DE this weekend then the engine is coming out. I have some special "mystery" CV grease a generous Pelican sent me a while back and I will re-pack both new axles with it. I don't need moon plates, this car is tech'd for every outing and checking CV bolts is part of it. Reality is my shop uses no washers at all and I have never seen a CV issue on any of his race cars. Me, I like using the schnorr's...

Can't find Schnorr washers on the M-C website? Found a supply in Utah, PMB Performance - http://www.pmbperformance.com/catalog/item/4055868/5749889.htm

Only problem is they want a minimum of $115 (UPS Ground) on up to over $600 for next day!!! to ship my 10oz box of 100 washers!! I'm calling them to see if it was a mistake...

[KTL]

The upside of the moon plates is they give the washers are harder bite surface than the softer metal of the CV boot's metal casings. That said, my '79 has plain 'ol bare screws (no moons, no serrated washers) and the paint-marked bolts always look good when I check them.

McMaster has the washers for sure. They refer to them as "belleville" spring washers and the Schnoor is the brand name, not the technical name. The sprung, serrated top & bottom M8 washers are part number 93501A030. Here's the catalog page

McMaster-Carr

$9.75 for 100 of 'em. More than you'll ever need for one car!

That grease you got, is that Lubemaster Premalube Xtreme? I got three cartridges of grease and some penetrating lube from Mike. Clear food grade grease, plain Premalube for wheel bearings, Xtreme for CV's and the penetrant. Seems like great stuff. I love the wheel bearing grease. Super sticky and water resistant. Lubemaster products seem to be in the same category as Swepco- heavy industrial. More than adequate for our tiny little cars.

[GaryR]

Originally Posted by KTL

McMaster has the washers for sure. They refer to them as "belleville" spring washers and the Schnoor is the brand name, not the technical name. The sprung, serrated top & bottom M8 washers are part number 93501A030. Here's the catalog page

McMaster-Carr

$9.75 for 100 of 'em. More than you'll ever need for one car!

That grease you got, is that Lubemaster Premalube Xtreme? I got three cartridges of grease and some penetrating lube from Mike. Clear food grade grease, plain Premalube for wheel bearings, Xtreme for CV's and the penetrant. Seems like great stuff. I love the wheel bearing grease. Super sticky and water resistant. Lubemaster products seem to be in the same category as Swepco- heavy industrial. More than adequate for our tiny little cars.

Yes, it's the same CV grease. Thanks for the heads-up on the "Belleville" washers from MC, strange how a search for Schnorr turned up nothing..