Turbo exhaust flange bolts - how to stop them coming out?

I have recently fitted my downpipe to my Garrett GT28RS with stainless allen head bolts but after a quick blast round the block two have completely come out and the rest are loose, does anyone know if loctite can be used at these temps? or should I use a different type of metal bolt?

 

Stainless bolts aren`t the way to go...

Proper studs and nuts are what you need.

 

Stainless is too soft - it stretches when it gets hot. Use standard studs and nuts and torque them to the spec of the standard manifold bolts and it'll be fine.

 

I suffered this problem for years with my old underslung GT28 even going as far as lock wire locking plates and even Titanium bolts wired yet they still came loose, I have now changed to a top mount manifold and dont have this problem, my theory was the extra weight of the larger turbo was stretching the bolts then the turbo comes loose and is allowed to move / wobble so the extra movement elongates the holes.

You need to brace the turbo to the block to give extra support.

 

Let's see If I can explain it. Make a shim/washerplate underneath 2 bolts, with some lips you can bend upwards. This prevents the bolts from comming lose.

Get it?

 

I use stainless stud, and stainless metal locknuts on the GT28 on my pulsar. No probs. Stainless id standard on gas turbine work, so not sure about the 'soft' comment. And these get hot, very hot.
Another way is to heli coil with a 'retained' type helicoil. A sort of female locknut method. The helicoil insert has a flat on one thread. Standard aero practise.

 

I'v just had same problem with my top mount gt30, i'v put on some copper nuts with squezed end which locks onto bolt

No problem as yet

 

no mention of nordlocks - I am surprised

 

Iv tryed them Bill on my Owen Developments gt30/ihi hybrid on bolts clamping core to the turbine housing and they still came loose!

Only proper lock tabs stoped them from undoing

Needless to say i am now running lock tabs on my gt30 as well

 

Thanks guys

 

You might find these bolts are not coming loose they are stretching, Trust me we had a year of this, we tried everything.

 

I will check that, but I think they are just coming loose.

Tried some studs but that's not going to work, there isn't the room to get the downpipe in position, it has to be bolts

 

lockwire?

 

I'm going to give some a try

 

"

If you've got a K04 on your 1.8T and don't have one of these brackets supporting the turbo, you need one, because the manifold has a hell of a lot of weight to support. Your Audi dealer can get one for you, or trawl the web for this part number.

"

It can be very helpful as Mook said...