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Discussion Starter #1
I'm going to be replacing the turbo-ehxaust manifold gasket in the near future and at the same time, replacing the downpipe and maybe a turbo upgrade.

A few years ago (but within ~7K miles) the prior owner had the front and rear main seals, oil pump seal, cam seals and a few others were replaced. The HFH and HFHOE also replaced at that time.

Alas, I've got a few minor leaks which I need to de-grease and track down, but is there anything I should reflexively replace or tackle while the turbo/downpipe are out? I'm going to try and remove the turbo/DP without having to mess with the exhaust manifold/studs. The best answer is probably to drop the motor and have at it, but I'm not excited about that.

Thanks!
 

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No reason to drop motor or even remove exhaust manifold for turbo extraction. If your simply pulling turbo to replace gaskets and install DP there isn’t any other bits to do. Should you decide to replace or upgrade then that takes much more work.
 

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Discussion Starter #3
Sounds good! I wasn't sure if I would have access to a commonly worn item that I wouldn't normally have.

One other question - I've read a bunch of threads and how-to's - It seems with the exhaust manifold in place you can get to two of the nuts holding the turbo to the manifold from above and the other two from below.

My question is - can you get enough torque on them to stay in place? I've seen these nuts back off with time and have tightened what I can from above with a wrench periodically. I would hate to go through all this work just to watch those nuts loosen up with time again.
 

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That's one of the biggest issues is trying to torque down the turbo nuts. The OEM nuts are self locking but what actually backs off is the studs. To help retain them I'd use double nuts (Brass normal type), high temp lock tight on studs and Nord locks. Can put these on from above so not reason to drop engine.

https://www.mainlandfasteners.co.nz/2571/Nordlock
 

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Discussion Starter #5
That's one of the biggest issues is trying to torque down the turbo nuts. The OEM nuts are self locking but what actually backs off is the studs. To help retain them I'd use double nuts (Brass normal type), high temp lock tight on studs and Nord locks. Can put these on from above so not reason to drop engine.

https://www.mainlandfasteners.co.nz/2571/Nordlock
Interesting. So you would place a nordlock washer then place 2 nuts and tighten down. OEM nuts or others?

Do you think I should prophylactic remove and/or replace (with lock-tite) the studs? For some reason I'm hesitate to mess with them if I don't have to....

If so, I've seen a few options mentioned in the past: the OEM studs, Grade 8 studs suggested by KO's site, supra studs 90116-10146 with a hex end on them (would they work here?), and I've seen Ti studs for the exhaust manifold at least from speedfactory.
 

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If the studs are locked down don’t touch them otherwise use one of the alternatives you mention. On the nuts OEM will work if new but double nutting using regular type with Nord locks. Think I found some 6 mm brass nuts that fit as not much room.
 

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PSA : Removing the exhaust manifold can be problematic.
Many people have stripped the exhaust stud holes in the cylinder head whilst removing the exhaust manifold.
This is repairable with timeserts , but of course, the car will be out of action much longer as you wait for the timeserts.
 

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PSA : Removing the exhaust manifold can be problematic.
Many people have stripped the exhaust stud holes in the cylinder head whilst removing the exhaust manifold.
This is repairable with timeserts , but of course, the car will be out if action much longer as you wait for the timeserts.
This.

When I rebuilt my engine, one of my studs broke off about flush with the head. Luckily it was out of the car and going to the machinist anyways, although they had a hell of a time with it themselves IIRC
 

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Discussion Starter #10
Thanks for the tips!

My plan is to remove the downpipe and turbo without touching the exhaust manifold nor oil cooler if at all possible. From all that I've read, I think I should be able to not mess with the oil cooler if I keep the elbow on the old turbo... I think. I took a look this weekend putting the car on a lift and man... getting to the turbo-to-manifold nuts seems like such a feat from below. I definitely couldn't get to the passenger/engine block side nut from below as is... looked like the oil hard lines were in the way.

From KO's site, he mentions unbolting the relief valve and 'moving the cooler' a bit for clearance to get the DP off, but aren't you sort of obligated to replace the o-rings then?

I'm planning on ordering HFH and HFHOE, new gaskets, oil cooler o rings (just in case), OEM nuts and some studs (just in case)
 

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To replace the HFHOE the cooler must come off as it forms the connection between coolant line and block. The only O ring which needs to be replaced is the one which forms a seal between cooler and block face. This is the one which causes the greatest issue as if you cannot keep it located within the grove it will become pinched and leak water in to the oil. I used a small amount of 'sticky' grease to hold in place during re-assembly. Should be some decent pics in the BGB if you get stuck.

jim
 
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