Oil in coolant, Speedo questions, A/C...

[Blurr]

Hey all,

So I ended up getting that 1990 Twin Turbo Z last weekend. Since I was already thinking of the swapping the current engine it in with a newer JDM replacment again, so I went ahead and purchased it with the problems it had.

Along side experiementing with this engine since its my first twin turbo, I pulled off the radiator cap and noticed that there was oil mixing with coolant. Since I have a couple other cars to drive while this one sits to be operated on, I wanted some opinons and questions about proceeding.

Ive only driven it a few times to test a few things out, and the engine even with the problems still pulls hard without hesitation. But, I noticed while parking a pool of oil every now and then, so I havent driven it since.

The leak on the drivers side ended up being a valve cover gasket leak, so ill need to get those replaced along side the oil pan gasket seal, and from what my mechanic said, tranmission seals. Im thinking either I pull the plenium and do the work myself or have it services and pay the costs. Which im weighing because it almost totals out to a new engine.

Questions I have for your twin turbo owners out there are:

If I do a full coolant flush after replacing the seals, can I get rid of some of that oil thats mixed with the coolant? I noticed some of the oil is in the lines too, its not too caked on, but its coated. How much damage can oil and coolant mixing cause?

I notice no white smoke to indicate I have a blown head gasket, or any black smoke coming from my exhausts.

Air conditioner
Does any of you know where I can pick up components to rebuild the air conditioner system? Looks like Ill need everything. The digital climate control comes on, but only blows to the windows and its locked that way, I cannot get air to come thru the vents. Is there any way to fix this or can some of you diagnose this so I can get some air to the vents?

Speedometer just became stuck
Whenever I turn the car on, It gets stuck at 20 MPH. I drive it, and it goes to 40 and gets stuck. For some reason driving the speedometer became stuck. It wasnt doing this when I picked it up and drove it, and just started happening. What I can I do to correct this? If I decide to get another cluster, there is a difference between the N/A ones and Turbo Clusters right?

[evildky]

run away!

seriously these cars are too cheap to buy and too expensive to repair and I'd sooner stab myself int he face than to buy another "low miles JDM engine" (search)

oil int he coolent is likley a blown HG, a HG has many possible ways to bow, oil into the combustion chamber is the most common but you can also get coolant in the oil, oil in the coolant which is what you have

and yes the tt cluster has a boost gauge, the n/a does not

[bentandbuzzin]

I second that. I bought my n/a with a blown passenger head gasket. I was getting coolant in the oil and in the cylinders. I pulled my heads and fixed it myself just to find out that the gasket was replaced before but was not torqued properly. I did the work to learn about the car because it was my first z and i say it was an experience. This was not my daily driver so i had plenty of time to fix it and which it took alot of that between getting to the heads and sourcing parts from Z1 and the salvage yards. So i would say if its not your daily, have plenty of time and want to learn about this engine...do it yourself and if not buy a GOOD non-jdm low mileage used engine.

[Blurr]

I just spoke with my mech. He says a power flush should get rid of most of the deposits from the radiator, a full inspection when pulling off the plenum will need to to be done and Ill get all the gaskets replaced from there.

Ya this isnt my daily, I have 3 other vehicles I can use to get around, but taking my time on this one since the previous owner really didnt take care of her at all.

I think right now if I catch it early enough and get the problems serviced without driving the car around, Ill be able to salvage the motor. I see they have engines on attarco for around 850.00. Has anyone here purchased a motor from them?

http://www.attarco.com/index.php?main_p ... ucts_id=42

Also, anyone have any ideas on the speedo problem im having? Was really odd, was working when I brought it home, then all the sudden just stopped and got stuck at 20MPH everytime I turn the car on.

[bentandbuzzin]

Check your oil to see if the color changed to a milky chocolate. You may have an internal leak. Since its not your daily do it yourself and that way you can do some of the delete's that would make the plenum pull easier. Check some write-ups on here and other z sites to get info on cleaning connectors and other services you can do so the engine will run good when your done. Also the only way i would buy a jdm engine is if i could see the checks in person and look it over myself before buying. I would stay away from those.

[Blurr]

When I checked the oil the other day, It looked like new synthetic that was put in, no discoloration and its not like milk chocolate, The only way to know for sure is draining all the oil out and going from there. Ill probably do that in the next couple weeks or so. What is worrying me is the coolant and oil mixing together, and hoping that one of these power flushes will remove some or all of those deposits to get rid of the mixture.

Ya I been reading on this and other forums, on pulling the plenum and deleting some of the hoses. Still doing research on it so I know exactly how to do it without making things worse.

Thanks for the help everyone, Im lookin forward to getting this up and running hopefully by summertime.

While the plenum is off I plan on redoing all the gaskets, and rehoning the heads if there is any warping. While im there I might as well replace the rings and other internals while its off. Any other suggestions on things I should be doing once the plenum is off?

[evildky]

you don't "hone" heads, you surface grind them, you hone cylinder

getting the oil out fo the coolnt system doesn't explain hw it got there nor does it prevent it form getting int here again

pulling the heads requires a LOT fo work and if you are paying a mechanic to do the work it's cheaper to sell the car and buy one thats not already tanked and as I already said search for "low miles JDM Engine" and see how many people got bad pallet engine, we can warn you but if you shoose nto to listen you accept the risk

[Blurr]

Thanks Evil, sorry didnt mean heads, I meant cylinder. = )

Ya, Im probably wont get a JDM motor, maybe a USDM replacement one.

[bentandbuzzin]

[evildky]

so are you going to rebuild or replace? why would you hone the cylinders of an engine you intend to replace? and if you intend to rebuilld the engine it's got to come out first! adn why rebuild an engine just because of a hg issue? if the oil pressure and compression is good I'd leave the engine alone and just do the hg's and maybe surface the heads

fyi you can buy a used engine for a few hundred bucks and might luck out or for around a grand you can rebuild your engine

[Blurr]

Come next week or week after I have plans to run it over to the shop for a compression check. If compression is good, and things are semi apart Ill have the cylinders done then. I get great deals from the mechanic Im with, and if he can do it under what the cost is for a new replacement engine, then ill go the rebuild route.

If things are already apart for replacement, Im lookin for advice on what else or what other issues anyone else has had, while things are apart to replace or check.

Ya I realize Id have to take the engine out to rebuild it. If im gonna go that far, I might as well replace the motor with a new one if Im going to be spending upwards of a grand or more.

[bentandbuzzin]

Come next week or week after I have plans to run it over to the shop for a compression check. If compression is good, and things are semi apart Ill have the cylinders done then. I get great deals from the mechanic Im with, and if he can do it under what the cost is for a new replacement engine, then ill go the rebuild route.

If things are already apart for replacement, Im lookin for advice on what else or what other issues anyone else has had, while things are apart to replace or check.

Ya I realize Id have to take the engine out to rebuild it. If im gonna go that far, I might as well replace the motor with a new one if Im going to be spending upwards of a grand or more.

Whatever you can afford...lots of stuff on these engines needs replacing. I say just about EVERYTHING!!!!

[evildky]

except that replacing the engine isn't replacing it with a "new one" the VG30DE has been out of produstion for years nw and any replacement you find will likely be as old as the one you take out