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Rb25 Exhaust Manifold Installed: 1 Bolt Hole Threaded

islade

By islade,
in Engines & Forced Induction

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islade Rising Star

islade

Posted
Posted

Hey guys,

Just installed my new exhaust manifold. It's a stock one with external gate attached to it. Anyway, 11 studs are very happily installed. The one on the top row second from the rear somehow threaded out the hole it's supposed to go into. So i've installed it gently, but if i put any real pressure on it, it spins freely as i've obviously damaged the threads inside the hole.

If all 11 others are attached securely, am I going to be okay, or is this going to be exhaust leak central?

If it is a problem, how do i fix this?

Thanks,

Isaac

The Mafia Grand Master

The Mafia

Posted
Posted

Exhaust leak central

Where is the stripped hole? Go and get a helicoil kit, and repair it. Its piss easy to do. Just make sure you have a practice somewhere if you haven't done it before.

Also, you might even be able to do it where it is without taking the manifold off.

JonnoHR31 Grand Master

JonnoHR31

Posted
Posted

aslong as both the manifold and head are straight and clean then it'll be fine, and given the top row is pretty easy to get to with a standard manifold anyway it cant hurt to see how it goes.

The Dan Grand Master

The Dan

Posted
Posted

aslong as both the manifold and head are straight and clean then it'll be fine, and given the top row is pretty easy to get to with a standard manifold anyway it cant hurt to see how it goes.

You can't be serious? It's going to leak no matter how flat both surfaces are. Not straight away, but eventually. Then it destroys a gasket, and other studs that cop the heat from it.

Do it once, do it properly. Helicoil as suggested above

JonnoHR31 Grand Master

JonnoHR31

Posted
Posted

so all the hundreds of standard cars driving around with 3-4 studs fallen out with no leaks are miracles? its a thick cast iron manifold, its not gonna bend from 1 missing stud

The Dan Grand Master

The Dan

Posted
Posted

so all the hundreds of standard cars driving around with 3-4 studs fallen out with no leaks are miracles? its a thick cast iron manifold, its not gonna bend from 1 missing stud

Didn't say the manifold was going to bend. It's going to leak though. And the studs fallen out of hundreds of standard cars is because the gasket is leaking, causing the hot gases to pass over the stud. If he puts this all back together without fixing it while it's close, then it WILL leak, it's only a matter of time....and from what I have seen, no more than about 3 months depending on what he does with the car

islade Rising Star

islade

Posted
  • Author
Posted

Cool

I don't think it's worth "seeing how it goes" because the inconvenience of removing everything again overpowers the "pay some mobile dude $88 to come fix it for me tomorrow)

Words stupidest question, but with the studs, does the "long threaded end" or "short threaded end" go into the head?

JE-R33GTS-T Apprentice

JE-R33GTS-T

Posted
Posted (edited)

As for studs I had one stuck in with loctite from the previous owner haha no wonder the back two cylinders had no exhaust gasket left I pulled the stud out with my fingers

Edited by JE-R33GTS-T
JonnoHR31 Grand Master

JonnoHR31

Posted
Posted

Cool

I don't think it's worth "seeing how it goes" because the inconvenience of removing everything again overpowers the "pay some mobile dude $88 to come fix it for me tomorrow)

Words stupidest question, but with the studs, does the "long threaded end" or "short threaded end" go into the head?

short end goes into the head

Smegul Explorer

Smegul

Posted
Posted

You can't be serious? It's going to leak no matter how flat both surfaces are. Not straight away, but eventually. Then it destroys a gasket, and other studs that cop the heat from it.

Do it once, do it properly. Helicoil as suggested above

what? I have 2 broken studs and have never had a leaking problem???

89CAL Grand Master

89CAL

Posted
Posted

you'll probably find that the cars that have broken a stud over time may or may not have a leak due to being on the car for hundreds of hot/cold cylces were the gasket has bonded slightly to the head and manifold. It's a bit hit and miss, I had 1 broken stud and didnt have any exhaust leaks but others might not be so luc

89CAL Grand Master

89CAL

Posted
Posted (edited)

you'll probably find that the cars that have broken a stud over time may or may not have a leak due to being on the car for hundreds of hot/cold cylces were the gasket has bonded slightly to the head and manifold. It's a bit hit and miss, I had 1 broken stud and didnt have any exhaust leaks but others might not be so lucky.

With a new gasket as said above, this will not work as the gasket will leak pretty quickly

Edited by 89CAL

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