So even though the elephants trunk to cam cover pipe has been removed and blocked this can still affect my blown turbo??
So even though the elephants trunk to cam cover pipe has been removed and blocked this can still affect my blown turbo??
yes because if its the turbo oil seals weeping it will be chucking oil into your ic pipework or down your exhaust!Originally Posted by 915nismo
do you have much oil in your ic pipework?
Not really , although I've only taken off the cold side to take the plenum off. I will check tomorrow though. I've never had much oil pressure when warm before so all this maybe highlighting something more serious
If it's blowing oil out the compressor side into the inlet the smoke will be blue.
Burnt oil smoke is blue - compressor seal, inlet valve stems, rings can all produce blue smoke.
Unburnt oil smoke is dense (hangs around) and white, that's exhaust valves or turbine seal.
To stop turbo seals leaking it needs a crankcase pressure much lower than exhaust/inlet pressure to suck gas in though seal instead of chucking oil out. At idle / off boost that can be achieved by connecting the PCV valve and a restriction in the breather inlet connection. A vent to atmosphere catch can gives a much higher crankcase pressure off boost than the stock breather.
If you connect breather system to the PCV valve you have to connect vent pipe to the inlet trunk. Drawing un-metered air from a catch tank will run it lean off boost.
Only way to stop it smoking is to put it all back to stock (with restriction or with one way valve) until you have a good turbo. Or connect PCV valve and remove the filter from catch tank, then connect that to inlet trunk.
Thanks for all your comments guysI put it all back together today, I used gasket sealant for the plenum to manifold and put my breathers back to stock.
So deep breath and turned the key....... It fired up and idled perfectly, no misfire at all!
I have a rebuilt T28 that I never got round to fitting which I'm going to fit next and see what happens??
To be continued......
at least you got it idling ok now! Good luck keep us updated!
ok, so got turbo off for swapping with my T28 and tought it would hurt to do a compression test before going much further.
These are the results, testing from the front towards the back (no1 being front)
Dry test 1=70, 2=75, 3=65, 4=65.
Then added a tea spoon of oil for wet test and repeated.
Wet test 1=210, 2=190, 3=180, 4=200.
Again im confussed.......any sugestions???
Last edited by 915nismo; 06-08-2012 at 12:06. Reason: .
Is it strange how when dry, they are all very low?
Does this mean all piston rings have gone??
Explain how you did the compression test, had you removed the turbo?
The engine needs to be up to operating temperature to do a compression test.
If I'm honest, I did drop the ball with that one. The turbo and manifold was already off the car so I couldn't run the car to get it warm for the compression test. Doh!
Would the results be higher or lower if the engine was warmed up first??
Last edited by 915nismo; 07-08-2012 at 11:11.
Higher I think, but if you've not done the test properly you could have made other mistakes that can effect the result too.
Here's a brilliant guide on how to do a cylinder compression test on a CA18DET.
getting up to temperature won't affect it that much - my old CA was managing 130psi across all four cold - anything sub 100 - I'd suggest a rebuild with new rings / hone is needed.
white '94 s13 200sx scrapped - mapped to 1.45bar. OS giken box, garrett GT2876R, 950cc injectors, ORC twin plate, nistune. 349bhp/325lbft @ 1.3bar CA18DET
white '96 s13 180sx - type g with more kouki bits- RB25DET, GTR steel twin turbo conversion, RB26 crank & rods. 2.6L VVT twin turbo, SR20 OSG box, OSG STR twin plate clutch, Z32 ECU w/ nistune.
current status: 180 a bit broken but to be repaired.
Did you hold the throttle wide open?
Yea I tested with full throttle.
I got an extra 40-50psi across all 4 when testing warm as opposed to cold on my old lump.
So imo yes it will affect it somewhat but if your rings are gone then not sure.
I 'tested' a friends VW engine and it failed, I then read the guide through and realised we'd made a few mistakes.
Re-tested with a warm engine, full throttle and all the plugs out and the compression was bang on.
So it pays to read thru the guide and make sure you've done it all correctly.
Sounds to me like you have a warn set of rings.
Personally if it wasnt causing any problems before I would put the stock breather system back anyway.
For the stock engine set up with stock turbo a catch tank really isn't needed IMO.
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