[mylesm]

I have an 82 ZXT.......


Engine was burning oil and it got dirty very quickly....
I asumed it was blow-by, because it did it during engine braking, so I decided to replace my rings.......


Took the motor out, got the vaves grinded, new valve seats, cylinder honed, all cleaned out and put back together... motor looks great...

http://members.home.com/mylesm/rebuild.html

put brand new hastings rings in....

now... here's the thing:

I've put 1000 miles or so on it since the rebuild, and today when I changed the oil, it was dirty... I thought that doing the rings would have made the oil stay cleaner longer... what's going on? aswell, I had to ADD 2 liters of oil during those 1000 miles....


So..... here's my question: obviously my rigns would have seated by now... so could the dirty oil and the oil consumption (yes it's burning, not leaking) be my turbo? I asked this before but nobody seamed to be able to answer me......

if I leave it idleing for 2 mins, it will be fine... after 2 mins it bellows blue smoke... or if I do ANY kind of engine braking, it burns aswell.....

if I hadn't just done the rings, I would say blow-by..... but.. there brand new...
and it's not very consistant either....

When I had the turbo out, I noticed SOME play in the shaft, however it sounds fine and I hit full boost no problem (everyone says turbos sound like marbles before they start to burn oil, altho right now I'm not convinced)


so should I do a compression test or is it my turbo for sure? why under engine braking? I'm thinking high oil presure... but with engine brakes, my throttle valve is closed... so the oil would have to be going through the exhaste, woudn't it?

someone help me out here... I have a spare turbo.. but it has a similar amount of play... altho I know that when I used it (on my old motor) it didn't burn any oil.....

 

[mylesm]

Awe crap... here's the pics...

 

[yo2001]

Re: New rings: Oil still goes dirty too quickly pl

New rings grind against the block more 'til they are broken in. Or may be your block is dirty

 

[hjspot]

Re: New rings: Oil still goes dirty too quickly pl

Sounds like worn valve guides to me , did you have them done along with the head work ?.If so it could be the stem seals or possibly the bores have glazed up letting oil past.( Did you run it in?)
Hope this is some help John.

 

[zmefly]

something else to remember....

todays oil has much more cleaning properties in it then before. its not unlikely to get dirty looking oil faster because of this. it used to be back in the day that you could judge your oil change by the look of the oil but this is no longer true. with all the detergents and cleaning agents in oil now you will get a faster discoloration of your oil.


james
pittsburgh pa

 

[mylesm]

Re: New rings: Oil still goes dirty too quickly pl

Head shop did the exhaste guides, but said the intakes were fine...
I"m really leaning towards the turbo here... but I want to know how I can find out for sure

 

[240Z TwinTurbo]

Sounds like turbocharger,

if it is puffing out blue smoke then it most likely the turbo if your motor has just been freshened up. When you start the car in the morning cold, does the smoking begin a minute later? It is easy to see if it is the turbo by removing it. You can also remove the inlet to see if any oil is puddling on the compressor side. Also, look to see if there is any visible oil that is coming from between the center section and the turbine housing. This would indicate and worn piston ring seal. Also, what kind of play does the turboshaft have? You should have 0 thrust play and very minor play up&down.

 

[240Z TwinTurbo]

One last note,

your turbo can leak oil into the hot side(turbine housing) and still run fine. This is as I stated before the signs of a worn piston ring seal on the turbine side. It will leak oil into the turbine housing and the hot exhaust will immediately burn it causing alot of blue smoke.

 

[bakachan]

Re: New rings: Oil still goes dirty too quickly pl

what did you hone the cylinder bores out with?
if you didnt get all the glazing off you could have seating problems
what kind of stone was it?

did you have much of a ridge at the top of the cylinder bore?
if so did you use a cutter to take it off before you removed the
pistons? you can damage the piston if the ridge isnt taken out

im not a fan of aftermarket piston rings. factory ones are the
best. perhaps they are of poor quality

 

[mylesm]

machine shop honed the block...

They used a special honeing tool, I'm not sure which one

 

[craig_57]

Re: machine shop honed the block...

Mylesm, The only true way to check ring seal is a leakdown tester. Your engine should hold 10% or less. A compression test will not indicate ring seal.It could very well be your turbo seal and bushing. However, some (but not all) piston rings have a mark on them and this should be installed facing up. Hastings make pretty good stuff,I wouldn"t be to concerned there.I really don"t think honing and rering is a good idea.After many miles the bore goes out of round,this will also cause a problem,Especially a turbo engine.The braking problem is strange,the only thing i can think of is all the oil in the pan is washing forward and being picked up by the block breather.You did reinstall the wire mesh back in the seperator didn"t you??You might try clamping this off and see what happens. Craig