stainless exhaust studs?

[fusername]

with all the headache given by broken exhaust studs, I want to nip this problem before it gets a chance to bud. I have a junkyard 914 that i am putting in my bus this week, there are no exhaust studs in it right now, I was able to pull all of them as a couple were bent. Can i replace them with stainless and stainless nuts to be able to remove it easily in a years time? I know stainless and aluminum will want to gall, so i will install it w/ lube, and that the stainless will loose its torque the first time I fire it up, so I just need to re-tighten them after the first cruise, but aside from taht, am i just aking for trouble, or is this a good idea?

otherwise I am going to use brass nuts on normal studs. I am lucky that my 2.0 heads are straight M8

[Glenn]

Stainless steel will gall when heated.

[david58]

You might consider using TimeSerts in the Heads.

[raygreenwood]

Stainless should not be used for any hardware on an engine. No matter which stainless...unless it is hardened and tested for a marine level of anti-corrosion....it has no place.

Stainless is actually quite soft as compared to ther steels we typically use for bolts. It deforms easily as compared to grade 5 and 8 SAE and 8.8 and 10.9 metric. Most stainless hardware is roughly the equivalent of grade 3 SAE at best. The sad part is that stainless has a really high tensile strength. Its "tough".
It does not have great shear strength. Its too easy to snap off a stainless rocker stud. But then....when you start to drill it out you will find out how tough and "gummy" it is. It will be an ugly job. Nothing on the head should be less than grade 8.8 metric (roughly similar to grade 5 SAE). Preferably all head studs should be grade 10.9 metric (roughly similar to grade 8 SAE). Ray

[typ4]

I concur with ray totally, stainless is not fun when it galls.

[fusername]

and this is why i ask before spening the money. strangly a web monster ate my earlier post, but i do love using stainless to connecter exhaust bits together. I have removed 3 year old bolts w/ my fingers on a vanagon exhaust system, they simply need a retorque after "break in". A new england exhaust, where winter is spelled salt. however I will not use stainless studs, not on my 914 heads.

[Joe vw]

I use stainless nuts with nickel antisize on normal exhaust studs. But never use stainless bolts or studs and nuts together with heat. On the type 4 you can double nut the studs so they don't loosen and they won't gall. Double nutting will protect the threads against rust and comes apart even years later- this is from experience.

[Piledriver]

Just remember, SS nuts should really not be used on SS bolts or studs... One or the other.

SS galls very easy, and with heat and time will become one piece with any encouragement.

Oh, Joe just said that... I guess it's worth mentioning twice.

[LanceT-IV]

Hello all-
Hopefully this won't be considered thread-jacking
I have looked without success for stock exhaust studs, no one lists them on their website including Jake.
I have two T4 projects languishing for the lack therof. HELP!
For whatever its worth - When I have had to change an exhaust system or disassmble (mostly T1) I have always used the copper/brass nuts with Permatex hi-temp anti-sieze which also resists rust. Once assembled thusly, I've never lost a stud again.
Still need to find some studs
Thanks for any guidence you might provide
-John

[Piledriver]

Which type do you need?

Straight 8mm?
8>9mm step?
8>10mm step? (repair)

Any decent hardware store or bolt supply should have the std 8mm studs.
(No, I don't mean home depot, I mean a hardware store)

[busman78]

Did you email the Type 4 Store and ask? Not everything Jakes has is listed online.

[Joe vw]

I found these:
http://www2.cip1.com/SearchResults.asp? ... ch1=Search
Expensive yes, but these are the correct ones to use.
The early 1.7 studs are 8x8mm if the threads are pulled they can be tapped for this size: 8x9mm
I don't reccomend tapping with the heads installed though. You can quickly make a mess out of your heads if you thread them crooked or wobble the tapp and make loose threads.

[Glenn]

Scott @ Germansupply.com has the real deal. Not cheap, but they are OE.

http://www.germansupply.com/home/custom ... at=&page=1

Part Number:
N 014 684 1

Stepped style Exhaust stud, type IV cylinder head, all 2.0l and 1.8l. Genuine VW. We only sell these geunine VW exhaust studs. Case hardened to grade 10.9 or better, correct rolled - not cut - threads. This part is now obsolete and no more are available except from old stock. We have a limited supply.

$CAD 8.70 ($US 8.21)

[fusername]

maybe I have just been lucky w/ my stainless hardware then. no galling, actually reused them on my bus, which I just took apart this morning, it had only been there ~3 months, but they still spun off by finger and I plan to reuse them again. wehere I saw ss nuts used on 'normal' bolts the bolt had swellled and rusted horribly around the nut, dissimilar metal perhaps? I don't know, just what I noticed. I can't recall if the nuts and bolts were originally installed w/ antiseize or not, if they were it was the silver permatex stuff.

for the exhaust stud area, should I use ss nuts or brass nuts on the threads? i like the idea of doubling up the nuts to protect the remaining exposed thread.

[Air_Cooled_Nut]

Just remember, SS nuts should really not be used on SS bolts or studs... One or the other.

SS galls very easy, and with heat and time will become one piece with any encouragement.

Oh, Joe just said that... I guess it's worth mentioning twice.

Wait. So it is NOT recommended to use a s/s bolt AND a s/s nut on an exhaust flange (as an example). You're saying that it should be a steel bolt with s/s nut OR a s/s bolt with a steel nut (one item steel, the other s/s)?

What if the fastener is not used in a heated area? And at what temperature constitutes "heat"?