1G Quick questions on replacing exhaust & turbo bolts & studs

[XC92]

I've been having rough idling issues on my 30 year old Talon TSi so I'm taking everything apart on the intake, fuel rail & exhaust, cleaning everything and painting where called for, and replacing all the gaskets, o-rings, bolts, studs, washers & nuts, along with the vacuum lines. Probably overkill but it can't hurt (if I do it right of course). I like things clean and fresh and 30 years does things to a car, so might as well "while I'm in there".

What I'm wondering about is:

1. OEM studs, bolts, washers & nuts ok?
2. Use anti-seize on exhaust studs & bolts, and if so what kind and on both stud ends?
3. What kind of RTV to use on bottom center stud that goes into oil galley?
4. How much torque when installing studs into head, with and without anti-seize?
5. Do I need an O2 sensor socket, or is an open-ended wrench ok (or crow's foot on a torque wrench when reinstalling)?

I've read up on proper stud removal technique, so I'm good there (PB, heat, double-nut, gentle, etc.). Anything else to watch out for or do on a stock 1G turbo setup?

 

[steve]

Since no one else has replied I'll take a stab.

If they haven't already, expect many of the exhaust studs to break.
I used stainless steel studs with the factory copper nuts/washers and a MLS gasket when I replaced my cracked 1G manifold.

I found some copper based anti-seize that was rated for 1800F but like the nickel based stuff that is only good to 1600F the grease burns up quickly and all you have left is metal dust.

The studs go in hand tight. I don't remembering needing any sealant on the lower center stud. What I do seem to remember is people have broken through into the oil galley by using studs that don't have a shoulder or too long and overtightened.

It's very likely you'll trash the O2 sensor getting it loose. I wound up using an impact gun and 02 socket to get it off Replacing it was part of the plan so I wasn't too put out by it.

Did this all a long time ago so maybe I'd misremembering.

 

[XC92]

Thanks. Permatex has nickel-based anti-seize that's supposed to go up to 2400F so I might get a small tube of that and use it instead of the aluminum or copper ones. I'll use lots of PB and be gentle when removing the old stud and O2 sensor. I really don't want to have to drill anything out of the head. I'll probably run the engine a few minutes to heat things up as that might help.

I assume that on the intake side things generally go more smoothly, because there's less extreme temp swings?

 

[pauleyman]

It may not be for you but I bought the jar of antiseize and I have what is likely a lifetime supply. I wrench regularly and my 8 yr old jar of regular antiseize is half gone. I just got the nickel stuff in the last year. It's 30$ for the jar but 7$ for half an ounce I couldn't do it.

 

[XC92]

I haven't decided which size to get, but the 2400F nickel seems like the one to get. I already have the gray kind in an 8oz bottle which will last forever for me. I also sometimes work on my titanium frame road bike which needs anti-seize so I can use it there.

 

[steve]

I assume that on the intake side things generally go more smoothly, because there's less extreme temp swings?

Don't know, that side has never been off.

 

[Christo]

I think my can of Copper Permatex is from the early 00's Still have about a 1/4 left in it.

 

[dwb]

I used copper anti-seize last time I did my exhaust manifold with all OEM hardware. Years later all the nuts came off without much hassle. At least on a 1g, the bottom middle stud does go all the way through the outer casing, so some high temp RTV is what I used there. I'm not sure it's an oil gallery but oil does drain past that stud.
I've never had an issue removing the intake manifold other than physically reaching the bolts/nuts.
I believe the biggest issue with the o2 sensor is the tight location. You're not going to get a box end wrench or much of anything other than an o2 sensor socket on it. If you removed the o2 sensor housing, then a box end wrench would probably fit. I wouldn't trust an open-end wrench as that might just strip the head. Those buggers get siezed on there pretty good.

Use lots of penetrating oil! I can't stress that enough. I'll even soak them overnight if they are being stubborn. Usually that's what I have to do for the manifold / turbo / o2 housing bolts, and especially the o2 sensor.

 

[XC92]

Thanks. I forgot to mention that I'm removing the manifold, turbo and O2 housing while still connected to each other, per the FSM, so would that make things easier?

 

[DSMPT]

would that make things easier?

To me yes. But if you are still using the stock coolant hard lines for the turbo, it may be better if you remove the manifold first, and remove the stock coolant lines from the turbo, then remove the turbo and the O2 housing together.

 

[dwb]

If you still have the one exhaust manifold to turbo stud, then yes, removing the whole thing at once is probably easier.

 

[XC92]

Yeah, everything's stock as far as I know. But can't I disconnect the hard lines from the turbo with it still on the car, perhaps from underneath? Or would I have to remove some cross and center members to get to it?

I might do that anyway to put some POR-15 on them as they keep rusting every time I prep and paint them with Rustoleum. I'm still a few weeks away from all this as I'm starting with the rear end first so I have time to decide.

 

[dwb]

Take off one end of the 90deg coolant hose by the thermostat. Unbolt the coolant banjo bolt on the front of the turbo. Unbolt the oil return line from the oil pan or turbo. Unbolt the oil feed banjo from the head. And of course the downpipe/intake. Don't forget to unplug your o2 sensor and wastegate actuator boost source.

 

[XC92]

Yeah, I'm basically removing everything, to clean, inspect and replace gaskets, o-rings and crush washers, and maybe some hoses. All the lines and banjo bolts are coming off too, and mating surfaces cleaned up.

I'll also derust and probably paint the manifold, turbo, housing, hard tubes, EGR flange, wastegate actuator, heat shields, brackets and anything else that's metal, with high temp paint, probably Duplicolor ceramic engine paint. I want everything to run well and look nice.

I'll also remove & clean the intercooler while everything's out. I should probably also replace the various air hoses that connect the air filter, turbo, intercooler and throttle, but I'll probably do that another time.

I recently replaced the radiator with an aluminum one and thoroughly flushed and cleaned the cooling system including heater core so I'm good there. I do need to inspect and clean the various temp sensors connected to the thermostat housing though. Also the O2 sensor.

Oh, and since I'll have a choice of what to put on that bottom center stud to seal the oil from coming through, which would be best:

1. Nickel anti-seize (which I'll be applying anyway)
2. High-temp thread sealant
3. High-temp RTV

I'm guessing that the anti-seize will be enough but maybe a tiny tab of the high-temp thread sealant? Or would high-temp RTV be better?

And while everything out, intake and exhaust side, should I think about replacing any of the freeze plugs? Is there a tap or other test to see if any are close to rusting through? Or should I replace them all, as a precaution?

I just bought 10 of them from Amayama since I was placing an order anyway and they're around $1.50 each so I figured might as well get a lifetime supply (they also fit my mom's 30 year old Camry, which is in far worse condition).

Yeah, I know, overthinking. But this isn't something most people do every day. After I'm done with all this, assuming I did it all right, I expect to never have to do any of it again as I'll sell the car before it's necessary.

 

[dwb]

Not sure I'd mix anti-seize and a sealant or RTV. They probably won't play nicely together. Personally, I used only RTV because that's what I had on-hand.

There wasn't a single bit of rust on my freeze plugs when I tore it down last month. 31yo virgin block. Honestly I'm not even sure how you remove them and it's probably something best left to a machine shop.

 

[XC92]

It's usually the back/inner side of freeze plugs that get rusty, from bad or old coolant or running a too-low coolant/water mix, so non-rusty front/outsides doesn't necessarily mean that they're still good. I suppose that a tap test might give some idea.

And removing them is usually a matter of tapping them so they fall into the coolant jacket, then pulling them out. There's usually not much room for them to drop so low that you can't get a grip on them, but you can tap a machine screw into it and attach a string to it just in care.

That's how I got the rusty one out of my mom's Camry engine after it rusted through and started leaking coolant.

 

[royal_flush]

Reopening this real quick, but has anyone been able to find exhaust manifold studs + nuts for a 1g 2.0L NA Eclipse? Parts stores I'm searching through keep ignoring the manifold part of the search and only yield exhaust piping bolts, which isn't what I'm looking for. Anyone have part numbers, thread type/stud length information, or a specific place they were able to find for these? I could remake my own, but again, I'd need more threading information first, just seeing if there's a faster way to get it by asking you guys.

 

[1990TSIAWDTALON]

See if this thread helps - https://www.dsmtuners.com/threads/what-size-is-that-bolt-nut-stud-fastener-1g-version.437697/
Do you know if it uses the same studs as a turbo model? I might be able to help out if that is true.

 

[XC92]

Reopening this real quick, but has anyone been able to find exhaust manifold studs + nuts for a 1g 2.0L NA Eclipse? Parts stores I'm searching through keep ignoring the manifold part of the search and only yield exhaust piping bolts, which isn't what I'm looking for. Anyone have part numbers, thread type/stud length information, or a specific place they were able to find for these? I could remake my own, but again, I'd need more threading information first, just seeing if there's a faster way to get it by asking you guys.

You can find the parts catalog for 90-94 DSMs here:

https://www.dsmtuners.com/threads/1g-plymouth-laser-and-eagle-talon-factory-parts-catalog-1990-1994.517692/

I've used it to track down hundreds of parts by now and it's usually very accurate, at least for the original part #'s, and if they've been superseded then a google search quickly reveals the replacement part # (Amayama below is really good at this). Always double-check but it's almost always been spot-on in my experience.

For actual parts, if you can't find them in auto stores, Mitsubishi dealers or DSM vendors, you can always try Amayama. Takes a few weeks and shipping can be a bit pricey, but they tend to have everything that's still being made and actual part prices are quite good. It's where I bought the bolts, nuts, studs & washers for my intake & exhause overhaul last summer. Mine's a 1G turbo but I'm sure that they have what you need.

Also check out RTM Racing. They're going out of business so everything is 50% off, and they might still have what you need.

 

[pauleyman]

Reopening this real quick, but has anyone been able to find exhaust manifold studs + nuts for a 1g 2.0L NA Eclipse? Parts stores I'm searching through keep ignoring the manifold part of the search and only yield exhaust piping bolts, which isn't what I'm looking for. Anyone have part numbers, thread type/stud length information, or a specific place they were able to find for these? I could remake my own, but again, I'd need more threading information first, just seeing if there's a faster way to get it by asking you guys.

Besides the above suggestions mitsubishi dealer software has been available to us for a long time. It's called ASA or the older version is CAPS. You can lookup parts by model and year and cross reference across different models. Not sure if it's available here but it's online. Mitsubishi ASA.
http://mmc-manuals.ru/Downloads

 

[XC92]

Besides the above suggestions mitsubishi dealer software has been available to us for a long time. It's called ASA or the older version is CAPS. You can lookup parts by model and year and cross reference across different models. Not sure if it's available here but it's online. Mitsubishi ASA.
http://mmc-manuals.ru/Downloads

Still works? I'll check it out sometime.

 

[royal_flush]

Update, I was able to find the right studs on extremePSI, so I'm good there. Also, mmc-manuals.ru looks like an absolute goldmine I hadn't found yet, so many thanks for informing me about it; we'll see if there's any good information/software there that AllData might not have. Thanks for all the quick replies and suggestions: now it's time to get my crusty dusty OEM exhaust off and get the headers and catback welded and on.

 

[XC92]

When I removed the entire exhaust pipe from my '92 Talon last summer it had a lot of rust on it but was still in remarkably good shape for its age and having had to deal with lots of snow, ice, slush and salt over the years. Took a couple of days to remove most of the rust, treat and paint it (KBS XTC), and some of the heat shields snapped off requiring me to use hose clamps to secure them back on (metal zip ties just aren't tight enough and you'll get a lot of rattle), but otherwise it's doing quite well considering its age with no joints appearing to be ready to separate or any signs of impending cracks or holes.

They really built these cars well and I don't care what Scotty Kilmer says.

 

[royal_flush]

When I removed the entire exhaust pipe from my '92 Talon last summer it had a lot of rust on it but was still in remarkably good shape for its age and having had to deal with lots of snow, ice, slush and salt over the years. Took a couple of days to remove most of the rust, treat and paint it (KBS XTC), and some of the heat shields snapped off requiring me to use hose clamps to secure them back on (metal zip ties just aren't tight enough and you'll get a lot of rattle), but otherwise it's doing quite well considering its age with no joints appearing to be ready to separate or any signs of impending cracks or holes.

They really built these cars well and I don't care what Scotty Kilmer says.

For sure. Mine is a lifetime resident of the Midwest, specifically Illinois. Our state is infamous for the nasty rust damage that cars will acquire over very much time here. The stock exhaust on mine is leaking pretty badly and rusting structurally in several places. Besides that, it's a great exhaust, but I decided since it needed at least replacing, I might as well upgrade it to a more performance-oriented setup anyways. After this I'll be looking at getting some of the rust damage to the actual body repaired and then finally getting it the new paint job this car very desperately needs .

 

[XC92]

For sure. Mine is a lifetime resident of the Midwest, specifically Illinois. Our state is infamous for the nasty rust damage that cars will acquire over very much time here. The stock exhaust on mine is leaking pretty badly and rusting structurally in several places. Besides that, it's a great exhaust, but I decided since it needed at least replacing, I might as well upgrade it to a more performance-oriented setup anyways. After this I'll be looking at getting some of the rust damage to the actual body repaired and then finally getting it the new paint job this car very desperately needs .

I guess that every situation is different and I've been lucky. Certainly lots of rust but nothing structural that I've found. I've yet to remove the rocker panels though as I've heard that those can get pretty badly rust damaged. Won't find out till next year when it's warm enough again to work on the car.

Good luck with your situation. A new exhaust for a 30+ year old car is not that unreasonable. My mom's '92 Camry's exhaust is seriously rust damaged and basically needs to be replaced, but since she drives it just a few miles locally each week at low speeds I've been able to patch it with exhaust sealant and wrap so far.