Help me keep my turbo attached

[quick6]

So I bought another MR2 turbo and drove it home from Hamilton (to Wanganui), by the time I get back it sounds like a tractor. I poke around to find that the turbo is only held on by 1 (loose) nut out of the 4 that should be present. So I replace the 3 missing ones and get them all tight drive another say 10km then allow the car to cool overnight only to find 2 of the nuts are loose again (read not even finger tight). Repeat the above process 4-5 times. I am using the correct nuts off another engine. The studs/nuts appear to be in good condition. When everything is tight it all seals up nicely. The car has solid eurethane engine mounts which cause a fair bit more vibration so I am guessing this is quite possibly the problem. The car also has a modified cast manifold (Wastegate) which could also be contributing. Anyone got any bright ideas as to how to keep this thing held together? Does Loctite make anything capable of withstanding ex manifold type temperatures?

[nz_climber]

lockwire!

have to get nuts with lockwire holes or drill them yourself

[IH8TEC]

haha, someones been scanning. i was looking for that pic when i tried explaining in to matt dunn, as he had same problem,

solid engine mounts is not the cause, well shouldn't be, i haven't had any problems, barry hasn't, few others i know haven't either.

but yeah lockwire will sort the problem

[pc]

Is the exhaust braced/bolted to the block after the turbo?

[nz_climber]

Brendon. I just found that on the net, good ol google images..

[Mike-]

spring washers?

[Dell'Orto]

Ordinary spring washers might detension with the heat cycling though.

[flygt4]

stiffer/solid engine mounts do create a lot more vibration though, i would think it to be a contributing factor.

[IH8TEC]

if that were the case, why have i myself and alot of others never had a problem, and yeah i find spring washers are crap on the manifold. i use flared nuts like most factory's use for exhaust systems.

next best option, lockwire them, pm matt dunn and see what solution he used.

[atmosports]

I've always just used aircraft grade metal lock nuts, obviously the ones with the metal locking insert rather than nylon like in nylock nuts which melts, never ever had one come undone on heaps of turbo cars. I always crank them up cold, then give the car a good thrash & let it cool down again & doubl check them.

Else you could use lockwire, a split pin/R-clip, a lock washer or two nuts is space allows & you want to drill some holes.

Else you could also get some high-temp threadlock like I've used on furnace fasteners before or run a dab of high temp silicone on the threads etc so that if it does come loose if won't rattle off completely.

[Crucible]

you can use the flange gasket as a template, and make up a couple of locking tabs out of something like .8mm panel steel.

basically just drill a couple of holes through each plate, they sit between the nut and flange, then you just tap the sides up so they sit against the nut flank.

and yep, always double check the bolts after it has been run and cooled down. Youll find they will probley come up a fair bit.

[RedMist]

Nord Locks. I use them on my offroad race car and have never had one fail. Never had a turbo race car before, but we have installed them on the new twin turbo offroader as I'm confident they wont release.

[method]

Use a high temp locking compound?

[ee904age]

Nord Locks. I use them on my offroad race car and have never had one fail. Never had a turbo race car before, but we have installed them on the new twin turbo offroader as I'm confident they wont release.

Agreed, we have them at work (McDonald Equipment) give them a go.

[quick6]

Heaps of ideas there, cheers guys. Those Nord Locks look like a simple solution so I will give that a go first. Lost another nut today, tightened before driving for 10 ish km and was gone when I got home. On the up side the other three were still tight.........

[matt dunn]

Nord Locks.

Where did you source them? NZ or overseas ?

[RedMist]

Nord Locks.

Where did you source them? NZ or overseas ?

All the fastener places in CHCH stock them. Blacks, Hylton Parker etc. They really are a fantastic product. One hell of a lot easier and quicker than wire.