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-   -   Broken Turbo Manifold Studs (https://www.rx7club.com/2nd-generation-specific-1986-1992-17/broken-turbo-manifold-studs-959738/)

gameover2145 06-26-11 05:08 PM

Broken Turbo Manifold Studs
 
Okay, so I pulled my factor S4 turbo in order to replace it with an S5, and in the process I find the front two exhaust studs are broken. One was just laying inside the heat shield and the other on was still in the motor, but fell out when i took the turbo off.

I'm not sure what happened, I've never seen anything like this before. It didn't look as if the turbo had been removed before, so I doubt they were over torqued. They are broken off a thread or two in the motor, so I can't grab them with vice grips.

For whatever reason, the car somehow did not have a noticeable exhaust leak the last time I drove it. Which is very surprising, considering I'm missing both studs on the front side.

Anyways, I know I need to fix this before I put things back together, I'm just wondering if anyone has any ideas besides pulling the motor, etc.

This car is fighting me every step of the way!

arghx 06-26-11 05:41 PM

So these are the front two studs, on the actual rotor housing, for the exhaust manifold connection?

gameover2145 06-26-11 05:45 PM

Correct, both the upper and lower studs on the front housing.

gameover2145 06-28-11 06:53 PM

Bump. Need to get this fixed, no one has any input?

HAILERS2 06-28-11 07:34 PM

I don't see it being fixed with the engine in the car. The studs need to be removed with a eazyout (EZOUT) or if that does not work then they need to be drilled out and a helicoil installed to replace the ruined threads (assuming the threads get damaged if the stud is drilled out).

http://www.brokentap.com/easy-outs.html Unfortunatley there's nothing eazy about eazy outs. I've batted about .500 using them.

GregW 06-28-11 07:52 PM

Figure out the depth, loads of pre treatment with tiger piss, beg,borrow steal a right angle drill, fresh sharp drill bits, easy out and a whole lotta luck. Better add shot glass and whatever hard stuff you like for happy or sad, cuz one of the two will happen.

AGreen 06-28-11 09:07 PM

If it's not sunk in to the housing, you could get a nut and weld it on the inside to the broken stud. That way, the heat from the welding can break the bonds, and most importantly the nut gives you something to put a socket on. You'll definitely need some PB blaster or something of that sort to ease the rust/corrosion.

Ford triton engines are bad about exhaust manifold studs breaking off in the aluminum head. Drill/easy out is the way I've always gotten them out without pulling the engine or cyl. head, but sometimes I had to break out the welder and do the nut trick. I always replaced them with copper (maybe copper plated) studs. Don't know Ford's reason for going copper, but it worked...

ROTAge244 06-28-11 10:40 PM

"If it's not sunk in to the housing, you could get a nut and weld it on the inside to the broken stud. That way, the heat from the welding can break the bonds......." <----- this is the best bet

gameover2145 06-28-11 10:49 PM

Thanks for the responses guys.

I was thinking of using easy outs, but i think given the location it would be hard to get with a drill.

The welding method seems like a good idea, however the studs are broken 2-5mm inside the housing so I don't know how easy it would be to get a nut on it

Barnett87GXL 06-28-11 11:14 PM


Originally Posted by gameover2145 (Post 10684772)
Thanks for the responses guys.

I was thinking of using easy outs, but i think given the location it would be hard to get with a drill.

The welding method seems like a good idea, however the studs are broken 2-5mm inside the housing so I don't know how easy it would be to get a nut on it

I've gone through this before and your best bet is to just pull the engine. otherwise you will struggle with the limited amount of space, the chance of breaking easy-outs (which are a bitch to drill out if the do break). And the fact that your studs are broken inside the housing makes the welding a nut onto the end trick almost impossible.

The biggest problem is that these studs are in the aluminum housings which has let them get nice and corroded and will also make it a chore to get them out.

Just speaking from experience. Pulling out the engine and doing it the right way is easier than fighting with it and making it worse than it was before you started.

sharingan 19 06-29-11 12:36 AM

I've dealt w/ a somewhat similar problem. The aluminum bolt that holds the fuel rail down snapped off in the center iron. Long story short I was able to find a shop that drilled out the center if the bolt (burnt up 5 bits) and removed it w/ a left handed drill bit.

Easy outs cause more problems than they solve, just stay away, especially if you are working in a confined space w/ bolts that are likely corroded.

Howru 06-29-11 12:39 AM

I had the same problem, only with the lower rear stud. The stud was broken below the surface.

2 broken EZ outs, a right angle drill adapter, a die grinder, and disassembling the engine to take the offending housing to a machine shop finally got it out. The guy at the shop said don't do it again.

It would have been a lot easier to just pull the damn thing and work on it while on a stand, but I wanted it running that day. :banghead:

arghx 06-29-11 07:05 AM

Easy-outs break often. I would not even attempt to use one.

gameover2145 06-29-11 08:46 AM


Originally Posted by Barnett87GXL (Post 10684813)
Just speaking from experience. Pulling out the engine and doing it the right way is easier than fighting with it and making it worse than it was before you started.

So what is the 'right way'? At this point I figure its not worth my time to try and fix this with the motor in the car, considering all of the problems and headaches that it could cause which would only result in more lost time and money. I figure I might as well do it right the first time around.

Hybrid G 06-29-11 05:06 PM

yeah i had the same problem last year, i first tried to weld a peice on and that did not work , then i resorted to easy outs that broke in the housing(DO NOT GET CHEAP EASY OUTS)

I finally had to pull the engine drill and tap the housing, i should have done that from the jump.

hybrid

PvillKnight7 06-29-11 07:08 PM


Originally Posted by AGreen (Post 10684645)
If it's not sunk in to the housing, you could get a nut and weld it on the inside to the broken stud. That way, the heat from the welding can break the bonds, and most importantly the nut gives you something to put a socket on. You'll definitely need some PB blaster or something of that sort to ease the rust/corrosion.

Ford triton engines are bad about exhaust manifold studs breaking off in the aluminum head. Drill/easy out is the way I've always gotten them out without pulling the engine or cyl. head, but sometimes I had to break out the welder and do the nut trick. I always replaced them with copper (maybe copper plated) studs. Don't know Ford's reason for going copper, but it worked...

+1

I'd hold a big nut over the spot and fill it with a good penetrating weld pool. You can't weld steel to aluminum and the heat will break any corrosion. Let it cool then soak it in PB blaster. Let it fully cool before you try to put any torque on the nut. Don't forget to chase the threads with a tap when you finish and use red lock tight and anti-seize on the replacement stud. I think I'd use two bolts to hold the manifold in place before I pulled the engine :D

dennis blackstone 06-29-11 07:51 PM

i broke one also
but idid not fix it the t2 ran the same with the 3 studs

gameover2145 06-29-11 07:52 PM

If at all possible, I'd like to avoid pulling the engine simply because knowing me, once its out I'm going to want to get it rebuilt/ported/etc. Which isn't really in the budget right now, so that means it would end up sitting until it was in the budget.

On the other hand, if I have to get the motor out in order to fix this the right way then it is what it is, and the motor will come out.

My only concern with the nut trick, is that the studs are recessed slightly (1, maybe 2 threads) into the block. Someone mentioned this not being able to be done unless the stud is flush.

AGreen 06-29-11 07:57 PM

Should be fine. As PVill said, you can't weld steel to aluminum, so get someone who KNOWS how to weld, and get the damn thing out of there.

It'd be easier with the engine out though. It's really not that hard to pull the engine, and it's not like you'll be tearing it apart once it's out.

bumpstart 06-29-11 07:58 PM

i bet next time you will fit all the exhaust hangers

PvillKnight7 06-29-11 08:20 PM

Forgot to mention, disconnect your battery and ECU before you weld on the car.

gameover2145 06-29-11 09:02 PM

Battery is already out and I'll disconnect the ECU before I do any welding in there.

And bumpstart, I didn't do anything to the car except buy it, drive it home and start taking it apart. Funny thing though, all of the exhaust hangers were on it. But the previous owner did mention the exhaust was redone fairly recently, so maybe the one it had before was in bad shape.

J5sense 06-29-11 09:45 PM

yeah your best bet is to take it to a mechanic who has experence and good quality tools. Ive turned wrenches for 10 years now in a shop and know first hand not to try removing a broken stud or bolt without a quality snap-on or matco extractor set.

good luck tho. worst case you have to pull the motor.

SpeedOfLife 06-29-11 10:46 PM

Build a huge clamp that will fit across the whole block and clamp the mani down.

gameover2145 06-29-11 10:58 PM


Originally Posted by SpeedOfLife (Post 10686241)
Build a huge clamp that will fit across the whole block and clamp the mani down.

I think bungee cords or JB weld will suffice


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