exhaust nut keeps coming loose

[san supra]

how do most of you keep your exhaust nuts tight?
i have a stock manifold and i am currently drilling the nuts for safety wire.

are there any other ways to keep them from loosening besides safety wire? (its a pain drilling the holes)

 

[RiyadYar]

thread lock ? or maybe its time for helocoil upgrade . such as this one
http://store.driftmotion.com/static/i-716exhauststudkit.php
good luck

 

[san supra]

thanks for the reply!
the heat from the exhaust makes the thread lock almost useless and i already have used it.
my head is all helicoiled
just the nut loosens not the studs

 

[ms07s]

lock washers or the groved nuts never failed for me.

 

[hvyman]

What nuts are you using? Do you torque them? I never have issues unless the studs are pulling out from the head.

 

[san supra]

got new lock washers.
groved nuts????

nuts a are all torqued and motor has 2k on it
nuts are from oreillys and are for high heat

 

[hvyman]

Are they exhaust nuts?

 

[adampecush]

lol, high heat...are you worried about the nuts melting?

they should have lock washers, and ideally be grooved opposite the flange surface, like OEM.

 

[gaboonviper85]

I doubt it's the nut....it's probably the stud slowly pulling out from the head...

 

[hvyman]

He already helicoiled them so unless the head is super soft i dont see why they would pull from the head.

Stock nuts dont have lock washers either so i dont see why that would be a issue.

Stock torque is 25ft lbs. I had 5 studs strip, helicoiled, and only torqued to 20ft lbs with stock exhaust nuts and in 25k zero problems.

 

[san supra]

ok this is the story
motor has 2k on it and i pulled it because i got a leaky timing case gasket due to a loose nut.
i went to check the torque and the NUTS were loose. The studs have not moved. I know this because i removed all the nuts and the studs are tight.

i have my nuts torqued (thats what she said) to 32 or 36ft\lbs....whatever the book says.

i was just looking for something easier than drilling out the nuts for safety wire cuz it a pain.


i do appreciate the replys. what do high horsepower guys do so they dont blow exhaust gaskets?

 

[hvyman]

Hp does not mean your going to blow exhaust gaskets. You have the same amount of pressure as a low hp engine. Exhaust spools the turbo so the intake side of the turbo can give more psi of air.

stock torque is 29ft lbs.
http://www.cygnusx1.net/Supra/Library/TSRM/MK3/manual.aspx?S=EM&P=57

Are you using exhaust nuts or regular nuts?

 

[mkiiichip]

The issue here is the oriley exhaust nuts and lock washers (junk).
Go to toyota and get some exhaust nuts, no lock washer, problem solved

 

[hvyman]

Agreed.

 

[san supra]

The issue here is the oriley exhaust nuts and lock washers (junk).
Go to toyota and get some exhaust nuts, no lock washer, problem solved

ok sounds like a plan

is there a problem using old ones? i might be able to get some.
so use the oem ones with no lock washers?

 

[hvyman]

Yes that is how it was out of the factory. Exhaust nuts without washers.
I reuse exhaust nuts all the time the only problem with reusing them is they like to stick to the stud.

 

[Dirt Track Racer]

you should try lock nuts. They look out of round. If they still come loose after that, replace the studs

 

[shaeff]

Just get OEM ones from Toyota. Don't cheap out, they're inexpensive. I never had any stud or nut back out on my Supra.

 

[hvyman]

Usually when you helicoil the exhaust stud threads you replace the studs and most of the time the nut is stuck with the stud so they come out as a bolt.

Stock Toyota nuts never had a issue ever.

 

[san supra]

Just get OEM ones from Toyota. Don't cheap out, they're inexpensive. I never had any stud or nut back out on my Supra.

cheap out is one thing i am not trying to do, i just didnt know how much better the stockers were designed

thanks guys for the info

i will be putting in an order asap.

one more question
what about the turbo to manifold nuts? I reused the stock ones and they came loose. yes i am using all the turbo braces.