Manifold to turbo bolts coming loose?

[DROOPY209]

Ok, on my red 92 talon tsi awd, it appears that i have a boost leak and broken exhaust manifold stud....

the other day i took off the upper heatshield that covers the ex. manifold and realized that the 2 14mm front bolts on the manifold to turbo were loose. I tighetened them back yesterday again and the 2 bolts still keep coming loose on their own.

im gunna replace the exhaust manifold studs, gasket and the gasket between the turbo and manifold soon. should i use some blue loctite to keep the bolts nice and tight in their?

 

[1fast97gsx]

I never bothered with loctite and never had problems. How many ft/lbs are you torquing them to?

 

[DROOPY209]

Im not sure how much Im torquing the 4 bolts to but i know its pretty strong.....not as strong as I tighten my lug nuts.

When I go WOT, I can hear a fat boost leak coming from the front of the engine. My car hits full boost quick, but theres no power at all, just the pressure that I can hear leaking out. I know its not the downpipe because I checked that out already.

I have tightend those bolts about 5 or 6 times already.....Im sure the gasket there is pretty worn out by now.

 

[1fast97gsx]

Well there's no way that gasket woulid cause a boost leak ... boost leaks can only be caused from the compressor housing up until the intake manifold including all vaccum lines. Anything after the head is considered and exhaust leak. You need to do a boost leak test and properly torque those turbo bolts as well. The spec my book has is tighten to 23 ft lbs and then turn the bolts another 65 degrees. Do this in a crisscross pattern.

1 4
3 2

 

[DROOPY209]

Well then i have an exhaust leak then....

If the gasket between the turbo-manifold and the gasket between manifold-head were bad, would that cause me to lose power?

Im assuming they would because that exhaust leaking out could have helped spin the turbo a lil bit better.

So, whats the best way to fix this?

 

[1fast97gsx]

It MAY cause a slight power loss ... depends on how bad the leak is. It definitly won't hurt it as much as a boost leak would. The proper way to fix this is to buy a new gasket and 4 new bolts from the dealership. Take the 4 bolts off, replace the gasket, and properly torque the new ones. If you have 3 bolts and a stud you can either try and remove the stud from the turbo or you will have to remove the entire exhaust manifold to change the gasket.

 

[flinguist]

Check your exhaust manifold for cracks. 1G manifolds are notorious for cracking, and if it's cracked in the right place it could contribute to the bolts coming loose.

 

[DROOPY209]

ok, i replaced all of my exhaust manifold studs with brand new stainless steel studs.

i took off the ex manifold gasket and it was split in 2 pieces. i replaced it with a new one

i took off the turbo-manifold gasket and it was missing pieces. i replaced it with a used one.

i torqued everything down, put everything back together.

now, it seems like my car is even slower then b4 i had the boost leak.

why could this have happened?

i already checked everything out.......all my vaccum hoses are on good. Boost controler is hooked up right......

 

[NOSLO2PT0]

Start the car and get it nice and HOT!! Then torque the turbo bolts down to 45ft/lbs while the manifold is HOT. When the manifold cools down to air temps, then the pieces will contract, and you will literally have about 75-100ft/lbs of clamping force. They will NEVER come loose again. OH, and to remove, do the same thing. Don't try to loosen them up on a cold motor. Get it hot first.

 

[GVR-4]

Make sure the downpipe is anchored to the block. The biggest reason these bolts come loose is because people get a bigger downpipe and don't reconnect it to the block.

 

[soulcontroller]

Don't try to loosen them up on a cold motor. Get it hot first.

haha i learned this the hard way on my 91 talon.

 

[trbotaln]

Maybe try and unplugging your battery and let your fuel trims go back and reset. It may take a little while for them to go back to normal.

 

[TurboDSM86]

haha i learned this the hard way on my 91 talon.

psshhh your not the only one. 102 bucks later and one new stud for my turbo from the machine shop