tomjohn51

I have pulled the cylinder head on my 82 ZXT, which has about 120,000 miles. The pictures below show what I found (I hope the pictures post correctly). Does anyone have any comment?






Also, I was surprised that the exhaust manifold was attached with bolts and not studs, except for the frontmost and rear studs. Is this the way it's supposed to be?

thxone

Not bad not bad. Yes the studs and bolts are supposed to be like that.

Now that it is apart, clean the hell out of it and put on a metal gasket.

nismo619

I just pulled the head off my 1983 280zxt -p90a i will post pictures soon hopefully i can get this digital camera to act right.

p.s. the valves look clean what type of gas or additive have u used ? please be honest , as i use Junk Yellow Bottle Complete system cleaner on my 1982 280zxt not one problem at all.

flightforlife07

looks normal all my cars cylinders stay pretty clean with little carbon buildup i use lucas injector cleaner and once in a while i'll dump some sea foam through the motor......... just wondering why you pulled the head if nothing was wrong seems like a lot of work for fun..

tomjohn51

I put only premium gas in the car, and have never used an additive.

I pulled the head, manifolds, and turbo for a number of reasons. The car was consuming oil, about a quart every 200 miles, and the turbo charger was not boosting. At about 3200rpm (it's an automatic) the car would lose power, occassionally miss, until about 3600rpm. The boost meter never got above about 2, no matter how much I got on it.

I decided to do a 'top end' rebuild, so I am sending the turbo and cylinder head out for a rebuild, replacing the intake manifold with a 'new' one which I have gotten coated with jethot, replacing all the emission control and cold start components (AAR, AAC, EGR, O2, etc.), and replacing all the injectors. I have already replaced all the vacuum hoses, fuel hoses, checked for leaks, cleaned all the electrical connections, and run the ECU through it's diagnostics with an ECCS Analyser. My compression tests, wet and dry, look pretty good, with all cylinders close and an increase of about 7 from dry to wet.

I am not a professional mechanic but am pretty knowledgable, and I wanted to do this work to solve my problems, learn about my car, improve the appearance of the engine bay, and yes, for fun.

NismoPick

You have access to an ECCS analizer!?! Cool... tho fairly useless.

Bleach

I wonder if the oil consumption and lack of power was just a bad turbo.

Looks oily inside but no carbon buildup.

duowing

I'm wondering if you had vacuum lines hooked up correctly. My Z was doing a very similar thing which turned out to be a vacuum leak, then turned out to be the vacuum line I had hooked up had a regulator on it or something that would basically close off the line, once I hooked up the other line it was fine. Either that or maybe your ECU plugs.

tomjohn51

I have an ECCS Analyzer. I use it as part of my tuneup routine and when troubleshooting. While not definative, it can be useful for providing direction when trying to find the source of problems.

I thought my oil consumption problem may be related to the turbo, but it looks clean and the J pipe didn't have oil in it. No broken fins and there doesn't seem to be any shaft play and the shaft spins freely.

I don't think I have any vacuum leaks, as I have replaced most all the hoses and the "take off the oil cap" test produces the expected results - the rpm dropped and the idle became rough. I could have screwed up and misconnected them when I replaced them, but I was pretty careful to do them one at a time. I could have bad regulators (check valves?), and I will look to replace them.

I'm hoping that the oil consumption problem is related to the valves (seals?), but my plugs look clean and are the normal tan color.

As far as the ECU, the analyser says it's OK and I did the plug/unplug thing many times.

PooFlinginMonke

You sure you have the nissan eccs analyzer for the 280zx turbo?

That's an extremely specific tester and cost about 5 grand.

NismoPick

Did you read what he said? I'm pretty sure he'd know if he had the ECCS tester... and $5k for one? That's weird... there's been several selling on ebay for $100-$300. Where'd you pull that $5k from?!

PooFlinginMonke

Have you yourself actually seen a 280zx turbo specific eccs tester?

I used them plenty of times in the last 19 years.

I believe he is describing a break out box.

NismoPick

Yep... I used them when I worked at a Nissan dealer.