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Engine Specific Info and Questions => IDI Engine => Topic started by: RunninWild on November 13, 2015, 05:42:53 pm

Title: Are turbo bolts 1 time use?
Post by: RunninWild on November 13, 2015, 05:42:53 pm
My 4 bolts that hold the turbo to the manifold have fallen out after maybe 50km. Are these 1 time use? I didn't torque them but I did make them tight. I'm confused why they Are falling out? Can I use locktight? Or would that break down from the heat?
Title: Re: Are turbo bolts 1 time use?
Post by: libbydiesel on November 13, 2015, 08:32:25 pm
They are not single use bolts, but they are very special bolts.  VW wants $15 apiece for them.  Despite their appearance, I believe they are stainless.  They are not magnetic.  I have never used loctite on them.  I use nickel anti-seize on them and torque them to spec (the spec is 33 ft-lbs IIRC).  I have never had one loosen on me.   
Title: Re: Are turbo bolts 1 time use?
Post by: RunninWild on November 13, 2015, 08:37:55 pm
Weird all 4 have came out and my turbo is just sitting on the manifold now. I think I got a few spare bolts sitting around cuz $15 is crazy! I didn't use a torque wrench but definitely put more then 33lbs on them. Its odd they came out so easily so fast. For now long they were on there youd think I had them finger tight.
Title: Re: Are turbo bolts 1 time use?
Post by: jmaddocks on November 15, 2015, 05:40:58 am
You asked about Loctite.  FWIW, 034 Motorsport has extreme-temp thread locker:

http://store.034motorsport.com/extreme-temp-thread-locker-turbo-rated.html (http://store.034motorsport.com/extreme-temp-thread-locker-turbo-rated.html)

It's not cheap.  In fact, it's so expensive, I'd exhaust every other option first (no pun intended). But it's nice to know that products like that exist.
Title: Re: Are turbo bolts 1 time use?
Post by: TylerDurden on November 15, 2015, 07:57:34 am
Hi-temp permatex gasket sealer will probably keep em from vibrating out. I use it on exhaust pipes to keep the slip joints from rusting together.

The real question is what's happening... excess vibration, sloppy threads, or...?
Title: Re: Are turbo bolts 1 time use?
Post by: Dakotakid on November 15, 2015, 09:38:56 am
....or, uneven mating surfaces.
Title: Re: Are turbo bolts 1 time use?
Post by: libbydiesel on November 15, 2015, 10:58:24 am
...improper torque.  It's hard to get to 33 ft-lbs with a 3/8" ratchet. 
Title: Re: Are turbo bolts 1 time use?
Post by: Blaizefed on November 20, 2015, 10:30:37 am
Those $15 bolts cost so much for a reason. They are a special alloy designed to cope with the turbo and the exhaust manifold moving around as they expand and contract from heat.   It's worth at least trying to get a 2nd hand set of them.

Not to say it's a must, I got away with using 8 mm nuts and bolts on an Aaz a few years ago as it was all I had to hand and then forgot about it till after I had sold the car. But if your not in a massive rush, at least snoop around for a set of the real ones. They cost that much for a reason.
Title: Re: Are turbo bolts 1 time use?
Post by: RunninWild on November 20, 2015, 11:27:16 am
I found 4 old ones I had in my bolt pile. Gonna swap the head this weekend and I will torque them properly
Title: Re: Are turbo bolts 1 time use?
Post by: burn_your_money on November 20, 2015, 12:03:45 pm
Make sure you have the downpipe/turbo properly braced to the block. If it's not braced it's not surprising that they rattled loose.