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DougC
This seems like a no-brainer, but is there any reason not to just use regular allen head bolts (or hex head) to replace the torx or 12star female bolts that are stock on the CV joints? What about the stock wave washers, wouldn't a lock washer work just fine?

Doug C
tat2dphreak
I use allen heads... got'em @ Elliot's Hareware in Plano...
bondo
If you get longer ones, there's enough room on the back for a nylock nut to help prevent them from coming loose.
tat2dphreak
QUOTE (bondo @ Aug 24 2005, 11:16 AM)
If you get longer ones, there's enough room on the back for a nylock nut to help prevent them from coming loose.

that's a GREAT IDEA!! too bad I didn't think of that sooner, it goes on my to-do list though...
Porsche Rescue
The proper lock washers are the ones with "teeth" (called schnorr washers I think), not the wavy ones. Likely used for a reason. I would use them with whatever bolts you use.
ArtechnikA
the Schnorr washer is conical, like a Belleville washer, in addition to being ribbed. the last set of CV bolts i got for the 911 came in as Allen although the ones in the car are triple-square. just make sure any substitute is at least the same grade as the specified fastener - 12,9; the 8mm fasteners used in the 914 are pretty highly stressed.
DougC
Yea, great idea Bondo.. I'll be going by Elliot's this weekend and pick-up some of these bolts in a longer length and some ny-lock nuts too. But I guess I'll use plain old lock washers 'cause I don't want to make a special order or trip for them. Hope that doesn't come back to haunt me unsure.gif

Doug C
Cap'n Krusty
QUOTE (DougC @ Aug 24 2005, 08:48 AM)
Yea, great idea Bondo.. I'll be going by Elliot's this weekend and pick-up some of these bolts in a longer length and some ny-lock nuts too. But I guess I'll use plain old lock washers 'cause I don't want to make a special order or trip for them. Hope that doesn't come back to haunt me unsure.gif

Doug C

It is interesting to see that the engineering resources of this mostly-amateur forum are collectively smarter than the engineers at Lobro, VW, and Porsche combined. Of course when the research is driven by low cost, you're apt to get different results than when the question of quality and longevity come into play.
The bolts in question are 12.9, and take substantial torque when compared to conventional 8mm bolts (nearly double). They DO NOT sustain a shear load, they hold the joint tight to the flange. The pins take the shear. The washers are used to reduce the potential for the bolts to back out. They depend on UNMARRED plates and the condition of both the curvature of the washer and the ribs on the washers themselves. Bolts stretched from previous overtorquing also contribute to failure.
I see no reason not to use the "old fashioned" inhex bolts, but the triple square bolts are an "upgrade" as internet car people are so fond of saying, and they're easier to torque, as well as causing less wear on the tool. Longer bolts of the SAME STRENGTH may be OK, but the locking nuts don't have a flat and parallel surface on which to seat, and there MAY not be room for them on the outer end of the axle. Split and wavy washers HAVE NO PLACE here.
Don't come looking to me for a used tranny because your axle ate your starter!
The Cap'n
jr91472
QUOTE (tat2dphreak @ Aug 24 2005, 08:13 AM)
I use allen heads... got'em @ Elliot's Hareware in Plano...

Hey Wayne, where is Elliotts?

My car came with allen head bolts, always worked well for me. But a couple are starting to get a little worn. Need some fresh ones.

JR
bondo
QUOTE (DougC @ Aug 24 2005, 09:48 AM)
Yea, great idea Bondo.. I'll be going by Elliot's this weekend and pick-up some of these bolts in a longer length and some ny-lock nuts too. But I guess I'll use plain old lock washers 'cause I don't want to make a special order or trip for them. Hope that doesn't come back to haunt me unsure.gif

Doug C

Tee hee. Not my idea, I read it here a year or two ago... All I did was remember it. biggrin.gif
bondo
QUOTE (Cap'n Krusty @ Aug 24 2005, 10:43 AM)
QUOTE (DougC @ Aug 24 2005, 08:48 AM)
Yea, great idea Bondo.. I'll be going by Elliot's this weekend and pick-up some of these bolts in a longer length and some ny-lock nuts too. But I guess I'll use plain old lock washers 'cause I don't want to make a special order or trip for them. Hope that doesn't come back to haunt me unsure.gif

Doug C

It is interesting to see that the engineering resources of this mostly-amateur forum are collectively smarter than the engineers at Lobro, VW, and Porsche combined. Of course when the research is driven by low cost, you're apt to get different results than when the question of quality and longevity come into play.
The bolts in question are 12.9, and take substantial torque when compared to conventional 8mm bolts (nearly double). They DO NOT sustain a shear load, they hold the joint tight to the flange. The pins take the shear. The washers are used to reduce the potential for the bolts to back out. They depend on UNMARRED plates and the condition of both the curvature of the washer and the ribs on the washers themselves. Bolts stretched from previous overtorquing also contribute to failure.
I see no reason not to use the "old fashioned" inhex bolts, but the triple square bolts are an "upgrade" as internet car people are so fond of saying, and they're easier to torque, as well as causing less wear on the tool. Longer bolts of the SAME STRENGTH may be OK, but the locking nuts don't have a flat and parallel surface on which to seat, and there MAY not be room for them on the outer end of the axle. Split and wavy washers HAVE NO PLACE here.
Don't come looking to me for a used tranny because your axle ate your starter!
The Cap'n

The only reason I see to change to standard hex head is if you ever need to mess with them while on the road. Any flaps will have an allen wrench. Of course this advantage is negated if you carry the triple square in your glovebox.

I think of the nylock nut on the longer bolt as just extra insurance.. they should still be torqued correctly and with the right washers. The nut should ony be snug, as you can actually compromise the grip by pulling the bolt from that end. (probably not an issue, but worth noting)

Cap'n: Do 911 CVs use differerent bolts and wahsers? I ask because I will be using 911 CVs and adapters, and I'm not sure what to use because I have never had a 911. It seems like it might be different because they use 6 bolts instead of 4 bolts and 2 pins.
tat2dphreak
QUOTE (jr91472 @ Aug 24 2005, 01:01 PM)
QUOTE (tat2dphreak @ Aug 24 2005, 08:13 AM)
I use allen heads... got'em @ Elliot's Hareware in Plano...

Hey Wayne, where is Elliotts?

My car came with allen head bolts, always worked well for me. But a couple are starting to get a little worn. Need some fresh ones.

JR

coit and parker, by the dunkin' donuts...

cool place... they have a TON of crap there...

the allen head screws there are grade 12 IIRC... I need to get the right washers(or the nylock nuts and longer bolts)

out of curiosity cap'n, what IS the correc torque I seem to remember someone saying that after 30 or so miles new bolts will loosen, but can't recall the tq. right off... hijacked.gif
ArtechnikA
QUOTE (bondo @ Aug 24 2005, 02:25 PM)
Do 911 CVs use differerent bolts and wahsers? I ask because I will be using 911 CVs and adapters, and I'm not sure what to use because I have never had a 911. It seems like it might be different because they use 6 bolts instead of 4 bolts and 2 pins.

i'm not the Cap'n but sometimes i do play his straight man on the Internet...

(the *really* earlly Nadella halfshaft cars used 4 bolts only, on the inner joint, and the outer was integral with the stub axle.)

SOME 911's use 6 bolts, some use 4 bolts and 2 pins like 914's.
up to '68 (the SWB cars) they also used 8mm bolts; from the LWB cars on, they are 10mm bolts.

oh -- 8mm CV bolts are torqued to 4,3MKg -- near 'nuff 30 lbs/ft. (for comparison, a "standard" 8mm fastener typically gets about 2,5MKg.)

a 911's 10mm bolts are torqued to 8,3MKg - ~57 lbs/ft.
DougC
It is interesting to see that the engineering resources of this mostly-amateur forum are collectively smarter than the engineers at Lobro, VW, and Porsche combined. Of course when the research is driven by low cost, you're apt to get different results than when the question of quality and longevity come into play.

I don't quite understand what this means confused24.gif But, the reason I'd ask such a question is because (AFAIK) the original style bolt head was standard in the early '70s and there had been (possible) improvements in hardware quality (Allen, etc.). Just didn't want anyone to think I was trying to outsmart the factory but rather use better (read upgrade) if possible.

Doug C
Cap'n Krusty
QUOTE (ArtechnikA @ Aug 24 2005, 10:42 AM)
QUOTE (bondo @ Aug 24 2005, 02:25 PM)
Do 911 CVs use differerent bolts and wahsers? I ask because I will be using 911 CVs and adapters, and I'm not sure what to use because I have never had a 911. It seems like it might be different because they use 6 bolts instead of 4 bolts and 2 pins.

i'm not the Cap'n but sometimes i do play his straight man on the Internet...

(the *really* earlly Nadella halfshaft cars used 4 bolts only, on the inner joint, and the outer was integral with the stub axle.)

SOME 911's use 6 bolts, some use 4 bolts and 2 pins like 914's.
up to '68 (the SWB cars) they also used 8mm bolts; from the LWB cars on, they are 10mm bolts.

oh -- 8mm CV bolts are torqued to 4,3MKg -- near 'nuff 30 lbs/ft. (for comparison, a "standard" 8mm fastener typically gets about 2,5MKg.)

a 911's 10mm bolts are torqued to 8,3MKg - ~57 lbs/ft.

Some LWB cars use 8mm fasteners, some with pins, some without. Some with 10mm bolts use pins, some don't. (923 CVs use 6 8mm bolts, no pins. Did some yesterday.) Some early LWB cars use really thick CV joints, some use thin, and bolt lengths and diameters are different. It can become quite a project to define all the various types. One thing for sure, they went to triple hex bolts in many applications and never went back. Big high weight an.)or high HP Audis use 10mm triple square bolts, and I've NEVER heard of a bolt failure. ALL Porsche and VAG CVs I've ever seen use the ribbed washers. Not sure about other European manufacturers. The Cap'n
messix
my triple squares were pretty ragged and i replaced them with allens.
i loc-tighted mine in. dont plan or want them comming out any time soon.
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