3SGTE Exhaust Stud Blues

[hoolio]

Anybody pulled the Exhaust manifold studs 'out' of the head whilst torquing the Ex Manifold nuts up??

Ive got 2 that seem to not be tightening up sufficiently,( that horrible soft Im about to shit the bed feeling when tightening them)They havent physically come out as yet!

Im a little reluctant to keep going till I gather more information on them.
I believe they are RH threaded into the head.
Anbody carried out a heli coil recovery mission on these before??

[KinLoud]

My better halfs Camry wagon had a similar problem. The new stud I put in (old one sheared off) must have got cross threaded when I put it in (DOH) and so it started to ease out a bit as I tightened it up.
Its the 4 cylinder motor so access to the exhaust side of the head was similar (in some ways) to your 3sgte.
$30 for a helicoil - works great.
I drove it to the auto machinist, removed the exhaust manifold, the did the helicoil and refaced the exhaust manifold as it was a bit warped. Took about 1 hour then I bolted it all back on... easy.
It won't be quite as easy as you have stuff like turbo etc. right there but the cost of the helicoil itself should be similar.

Ken
Taupo
021 408 863

[hoolio]

Thanks KinLoud
I hate to admit it but I think thats the track Im headed also.

[TWSTD]

I just did this too on my 3sgte in the caldina Its the far left hand side top as you are looking at the engine from the front of the car... the absolute WORST one to get to. Looks like will have to remove alternator etc etc to get to it to fix it.

Anyone in AKL suggest a place to go to?

AL

[hoolio]

I fixed mine myself, wound the studs out of the head-complete with the heads' threads!
Got the correct helicoil/Tap & drill & went nuts-carefully mind, presto!

The studs were 10 x 1.25 (I dont know what yours are) & I replaced those too, it would be a shit sandwich to put the old ones back in & then have em snap off in the head.

I dont know what a shop would charge but the actual repair took about 3/4hr for 2 studs.
(pulling everything off & putting it all back on would push the bill thru the roof)

[TWSTD]

I had one snap off previoslly - in the same hole aye... luckily there was a small enough fragment protruding to get the broken one out... im certain i didnt cross-thread it when i put the new stud in... ive had the exhaust manifold on and off about 4 times since and its decided to go... grrrrrr

Hey dont the heli-coils need to be welded in place? or do you drill out a large hole and tap it and they thread in?

[hoolio]

Heli coils are a stainless coil (looks like a spring of sorts before they are used) with a diamond profile.
The correct size hole is drilled & then tapped, the helicoil is wound into the newly tapped hole & its internals now form the repaired thread for the stud/bolt etc.
If done correctly are very strong.

[TWSTD]

thanks for that explanation. I assume engineering supplies shops would be the place to get them?

[blitza]

hey twisted/ all, as my gtt is finally going,( ok so I just wanted to say that)
ummm, had some studs break orff in the head, e-z out'ed them, replaced the lot with new ones as they are a reasonable price from toyota. not a dum idea to use plenty of neverseez or copper grease or some other kind of hi temp goo when putting the nuts holding the manifold on. saves a lot of grief. I also have the correct size heli coil kit, am in west aucks.

[TWSTD]

ahh yeah - cool - maybe we can meet up this weekend or something? Im on the shore - but can travel My cell is 021 262 2249

AL

[Dell'Orto]

When I removed my manifold the other day, I noticed a couple of the studs had alloy around the thread, I assume from being overtightened when it was last off...has anyone ever had helicoils done on an MR2 3SGTE? One would assume they're a bit trickier to do than a Celica/Caldina

[Lloyd]

I've ripped the insides out of a thread in the head of my Levin on the exhaust side. Helicoiled it and had no worries after that... well, apart from the others that I probably should have done at the same time.

Helicoil is supposed to be stronger than the original thread btw