BEGI-S GT2554r with intercooler 10PSI(bad oil seals?) - Page 2 - Miata Turbo Forum - Boost cars, acquire cats.

Welcome to Miataturbo.net   Members
 


Reply
 
 
 
LinkBack Thread Tools Search this Thread
Old 06-30-2012, 11:41 PM   #21
Junior Member
Thread Starter
 
Join Date: Dec 2008
Posts: 72
Total Cats: 2
Default

Quote:
Originally Posted by fwMiata View Post
do the compression check.

for my gt2554r I used pipe thread to -10 AN fittings in the pan and for the drain and -4 AN for the feed with the ATP .035 whatever restricter. No smoking and my drain line is just run down there, no real urgency to it...

they are right, it sounds like something else is messed up. maybe the PCV into the intake manifold is dumping oil in or not venting right causing blowby.
Yup I'm stumped, my oil feed and drain is essentially identical to yours in inside diameter. The PCV is blocked off, the other valve cover vent doesn't run into the intake anymore, it has a filter on it now.
Sclippy96 is offline   Reply With Quote
Old 07-15-2012, 07:57 PM   #22
Junior Member
Thread Starter
 
Join Date: Dec 2008
Posts: 72
Total Cats: 2
Default

Update: I've got good news and bad news, the good news is the turbo is fine, I removed it from the car and i am still seeing lots of oil smoke from the exhaust. The blades look fine and has very little shaft play still. Bad news is I can't diagnose what is going on inside the engine yet, I did a compression test and the numbers are the same as from when the car wasn't smoking before the turbo install. I'll do a leakdown test next to see if the problem is the valve seals or the rings. I am most likely looking at picking up a decent used 94-97 engine and swapping it in at this point. It's odd because if it wasn't for the massive amount of smoke coming from the exhaust the car drives fine with plenty of power.

Compression numbers from after oil smoke/turbo install/deinstall on left, before turbo install on right.
Attached Thumbnails
BEGI-S GT2554r with intercooler 10PSI(bad oil seals?)-20120714_171658.jpg  
Sclippy96 is offline   Reply With Quote
Old 08-12-2012, 07:15 PM   #23
Junior Member
Thread Starter
 
Join Date: Dec 2008
Posts: 72
Total Cats: 2
Default

Update 8/12/12:

I have narrowed down the likely source of my oil burning to a stuck oil control ring on one of the pistons. I will try a combustion chamber soak to free the stuck control ring before I resort to pulling the engine.

Some products I might try for the combustion chamber soak are the new WD-40 Specialist , Marvel Mystery Oil in the crankcase, and possibly Piston Kleen as well.
Sclippy96 is offline   Reply With Quote
Old 10-25-2012, 10:48 PM   #24
Junior Member
 
Join Date: Oct 2012
Posts: 55
Total Cats: -69
Default

so what was the final result?
Boost93 is offline   Reply With Quote
Old 10-26-2012, 01:34 AM   #25
Junior Member
Thread Starter
 
Join Date: Dec 2008
Posts: 72
Total Cats: 2
Default

Quote:
Originally Posted by Boost93 View Post
so what was the final result?
I tried a combustion chamber soak for a stuck oil control ring to no avail. I then replaced the valve guide seals, without pulling the head as seen here:
(this job was way easier with compressed air in the cylinder instead of rope, but riskier if the air fails and the valves drop. The valves cant have any give when you try to pound the 2 piece seal keepers onto the valvestem, and the rope was giving me fits until I threaded compressed air into the sparkplug hole.)

But that didn't fix it either. While the camshafts were off the head I finally found a threaded/quick-release hose to connect to compressed air, I pressurized the cylinders with 120psi and #1 and #2 held pressure with minimal pressure drop. #3 slightly leaky but was acceptable, #4 was shooting air past the seated exhaust valves and past the rings, I could feel the air coming out the exhaust and heavy sounds from dipstick hole. The air coming past the rings on #4 was expected, but the air shooting past seated exhaust valves may indicate a chipped valve or seat, in any case it wouldn't be the cause of an oil leak, especially since it has fresh valve guide seals now.

At this point I have narrowed it down to bad rings on #4 cylinder, and a bad head on #4 too. Rather than a rebuild this motor or get a used engine, I am leaning towards purchasing a low milage '94-95 miata with good leakdown that already has a torsen, and swapping my parts over to a new chassis.
Sclippy96 is offline   Reply With Quote
Old 11-24-2012, 01:58 AM   #26
Newb
 
Join Date: Nov 2012
Posts: 3
Total Cats: 0
Default

update? Having similar problem.
Pablo97 is offline   Reply With Quote
Old 11-25-2012, 01:46 AM   #27
Junior Member
Thread Starter
 
Join Date: Dec 2008
Posts: 72
Total Cats: 2
Default

Quote:
Originally Posted by Pablo97 View Post
update? Having similar problem.
Bad piston rings, motor needs a rebuild.
Sclippy96 is offline   Reply With Quote
Old 11-27-2012, 02:15 AM   #28
Newb
 
Join Date: Nov 2012
Posts: 3
Total Cats: 0
Default

Damn bro... good luck on the rebuild.
Pablo97 is offline   Reply With Quote
Old 04-03-2013, 11:57 PM   #29
Junior Member
Thread Starter
 
Join Date: Dec 2008
Posts: 72
Total Cats: 2
Default

I put a another engine in the car, and tore the old one apart to see what was wrong...



It turns out Piston #4 had a significant amount of metal missing from 2 places on the edge of the piston face, and when those chunks broke free and got pulverized they messed up the exhaust valve seats on the way out of the engine. I should thank my lucky stars the pieces of piston didn't seem to damage the fins in the turbo on the way out.

It goes to show how robust these engine are that the motor still made nearly 200WHP with such damage internally.
Attached Thumbnails
BEGI-S GT2554r with intercooler 10PSI(bad oil seals?)-altwoxe.jpg  
Sclippy96 is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
OTS Bilstein to motorsports ASN conversion stoves Suspension, Brakes, Drivetrain 5 04-21-2016 04:00 PM
Moroso Air Oil Separator Catch Can Aroundcorner Miata parts for sale/trade 2 10-01-2015 04:20 PM
Time to start learning and play with tuning The Gleas MEGAsquirt 3 10-01-2015 10:30 AM
Walbro 255lph Fuel Pump $50 lsc224 Miata parts for sale/trade 2 10-01-2015 10:17 AM
Leaky Wilwoods mx592 Suspension, Brakes, Drivetrain 1 10-01-2015 01:45 AM


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 06:52 PM.