Still smoking... getting pissed...
 

Ok someone enlightnen me here. Im a fully certified mechanic and have been for over a decade.. however this miata has about got me at wits end right now..

So heres the deal.. did a head gasket about a month ago due to an external oil leak and low compression on cylinder #1.. i believed it was from the headgasket cus when i wet tested i got the same #s. So being that i didnt have time to send the head out to be resurfaced i checked it with a straight edge and it seemed true. Didnt fix the compression issue... or the ongoing oil leak i cant seem to track down thats coming from the drivers side but from above the oil pan.. probly still the headgasket.. probly a warped head.

Anyhow i replaced the turbo cus the oil seals blew with no oil restricor to the china charger.The smoke let up alot but not all the way. I then replaced the oil soaked glass pack muffer.. took her out for a good beating and the smoke seemed to subside. So at this point i though awlright were good to go(except the still unpinpointed oil leak).

So here i am a week later and this mfer is blowing smoke out the tail again! Its when i boost then shift into the next gear and punch it, it blows a flipping cloud.

So ive got about 170 psi compression on 3 of 4 cylinders and 120 on the last.

Does this smoke sound like another crappy blown china turbo(it has less than 500 miles on it) or has my motor had it? Like i said only smokes after i boost it good. But also when i boost is when it leaks the oil out of the motor from wherever its coming from.

Does this sound like an internal engine leak or a crappy turbo striking again?

Im supposed to be picking up a new engine on thurs (if this guy doesnt blow me off again) But i really want to pinpoint the problem instead of throwing parts at it(not my style).

What do your charge pipes look like?

---- ! Y$!*&@$ I typed a message and lost it...Anyways:

Oil leak:
Its possible that its the VC or the cam seal. wipe off the BACK of the timing plate from the drivers side and see if you come up with oil. (not sure if the steering pump gets in the way or not).

Shitty oil plume:
Its very possible that its the engine. I would say you should do a leakdown test because they are more accurate and from where the leak sounds, you can tell if its valves (either exhaust or intake will make noise) or crank (noise will come out of the dipstick hole or Oil cap).

my thought is valve seals.

Ok im pretty sure its the engine... pulled the turbo off today... everything looked dry, charge pipes, turbo inlet and the hotside showed no signs of oil.. left the turbo sitting on the bench hotside down just to see if any oil came through.. dry. So ima go with engine.. kinda blowing my plan of building the engine im bout to pick up but oh well. Gona just go through do headgasket, resurface the head, valve seals, and all that stuff up top, pull the pan weld a bung in and redo that gasket and do front and rear main seals before it goes in. Also gona see what i can throw together to have a decent clutch. Car has a hd pressure plate on it, i just hope its not all warped. The new engine had what looked to be a fresh clutch on it so maybe i can use whatever disc is in there in combo with my pp to get a decent hold. Unfortunatly i dont have the cash to do the fm happy meal like planned.

I just hope the owner doesnt ---- with my check this week or i may be in the market for a job also.

Oh also found in my turbo removal that my mani is cracked... got a buddy whos a wiz with a tig though so ill just have him weld it up while i have it off.

So ima swap this engine out and then ill use the smoked one as a base to build off... I know the cylinder walls are all good cus when i had the head off i could still see crosshatch in the walls, not to say i wont measure the bore for inconsistencies.

Sucks but i guess thats the name of the game when boosing a previously boosted miata with over 125k. Im a bit calmer now, and im a flipping master mechanic so its not like its something i cant take care of.

Its not a bad idea to just use the engine you are about to get and build this one instead.

When your turbo oil seals went out was it on the compressor or turbine side?

Both sides... didnt run a restrictor on the oil feed like i was sposed to on the old 20g.. bout to rebuild it though and give it another run.

This is what i did today after work

https://www.miataforumz.com/attachme...ine=1331255465

Ok got some insight into the smokey problem... Heres exhactly when it happens... I go do like a nice long boost pull on woodward top out 3rd gear.. then instead of actually hitting the brakes i let the engine slow me back down to the speed limit... This is when it starts smoking, then if i get back on it or next time i give it gas it blows a cloud.

However if i boost the piss out of it and take it out of gear instead and hit the brakes ....WALLAH! NO SMOKE! WTF?

Any ideas or guesses yall? I mean im gona put this other engine in regardless but i just wanna know whats causing this cus its got me stumped.

leakdown test...