leboeuf

iTrader: (1)

Any chance you're missing that metal shield that goes between the turbine and the chra housing?
Obviously a long shot here...

Part E below (picture randomly grabbed from interwebz)

turbofan

iTrader: (1)

Nope, that's definitely still there.

18psi

iTrader: (76)

to lose part E his whole turbo would have to come apart into pieces

what if the bolt bolt holes are clogged or something? dunno if that was already checked

EO2K

iTrader: (37)

Blind holes, right? Jammed up with crud is a good call. Also in this line of thought, maybe the bolts are too long? Or the holes were not tapped with a bottoming (giggity) tap?

aidandj

iTrader: (5)

But this turbo was good for years and years, and from what Ed said the clamps were still tight.

turbofan

iTrader: (1)

But the bolts weren't all tight. Like I said, after cutting off the safety wire I was able to tighten the nuts and it did snug things up.

I reached out to @yank at PRE hoping they might be able to source some new clamps and bolts for me, then I'll clean it up and put it back together.

aidandj

iTrader: (5)

Ah ok. When we talked you made it sound like they were full tight.

18psi

iTrader: (76)

I think I have a brand new set of bolts/tabs for a Garrett hotside if that's what you need?

turbofan

iTrader: (1)

I think that probably IS what I need. The previous ones were safety wired tho... Let me see if I hear back from @yank on spiffy racekor parts

aidandj

iTrader: (5)

AFAIK tial housings switched to inconel bolts at some point.

18psi

iTrader: (76)

mine are whatever comes in the Gpop shop rebuild kit.

turbofan

iTrader: (1)

I might want the clamps... any chance you could measure the thicknesses of them?

Do they look like this?



I'm betting they don't. I bet they look like this:

turbofan

iTrader: (1)

Alright, got resbond and new safety wire, cleaned the mating surfaces with some 1000 grit, and reinstalled everything. I determined that the safety wire had kept the bolts from backing out completely, but they had definitely loosened... just enough to let the turbo rotate a bit. Clamped it all down, everything is nice and tight. First time playing with safety wire. It was fun! And I'm pleased with how it came out.






After cursing at the vband clamps for a couple hours, I got the car back together. It was leaking here, so I had to re-do that joint. Thank you, Chan-nel Locks.







Put the nose in the air and started burping:



What's this?



****. Check out the floaties at the end...


Catch can is... real nasty.




Pulled the valve cover to have a look. Thankfully everything looks purdy under there:


I didn't have time to mess with it further, so I towed it to the storage unit and put it away. I was originally going to wait til June to finish it (should have my own garage by then) but might work on it again sooner.

turbofan

iTrader: (1)

Aidan suggested that I do a coolant pressure test. I'm thinking to do that, drain the oil and have a look.

Thinking about one of those Cometic MLS gaskets. Will have to read up on them a bit. I should be able to get decent pricing on an OEM MLS gasket, so will have to determine which is best.

I also need MS help. Wish I'd learned it sooner. I had noticed some leaner AFR's lately, seemingly random... maybe thrown off by the altitude? I don't know. but I'm betting that's why the HG is (likely) toast. Not sure where else it'd be mixing.

Would love any input y'all want to offer.

shuiend

iTrader: (24)

I have been using eBay MLS HG which cost about $25-$30 for years without any issues. I have had them next to an OEM one and friends could not pick out which is which.

turbofan

iTrader: (1)

Thanks for the input. However, I don't enjoy this work so I'll be looking to buy the BEST head gasket, not the least expensive.

shuiend

iTrader: (24)

I don't think any are better or worse then any others. Unless you needed one for oversized pistons. I can probably count on one hand how many people I have seen over the years with HG issues.

turbofan

iTrader: (1)

After researching, looks like I'll stick with OEM unless someone suggests something that's better than OEM. I believe my engine is stock bore (it's got an OEM gasket in there now) so I think I'll just do OEM again.

Thanks again Lars.

codrus

I agree, the best head gasket for a Miata is the OEM one.

--Ian

Mobius

iTrader: (2)

I've never seen anybody whose opinion I trust suggest anything other than the OEM gasket. It's solid.