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OK basically i have a 945 b230ft that uses oil like its a 2 stroke, for a year I have persued this, I have reduced the oil use to about 1/2 LTR per 100 miles by curring various external leaks etc......
what i have done:-
new turbo
front engine seals
new oil cooler
new seal on filler cap
removed cat / replaced mid box
tried various oils (currently 10w40 castrrol gtx magnatec semi sythetic)
cured ALL external oil leaks
replaced oil breather box (twice)
cleaned flame trap & associated plumbing until im bored
run 'snake oik' oil cleaner through the car
run REDEX through the cylinders
changed plugs/leads/dizzy cover & rotor arm
changed air filter
checked ALL air intake plumbing for obstructions
performed compression test (results within Haynes specs, circa 135-140psi)
now i STILL have oil in my turbo tubes from the turbo to the intercooler..not huge amounts but enough for 'pools' under the ledges (eg where the rubber tube meets the intercooler neck), and I THINK most of the oil is comming from the breather pipe FROM the flame trap housing.....but im not sure....
now either i have a turbo that has been defective from new in EXACTLY the same way as the one that was replaced, or I have a situation that causes turbo's to leak oil this way (restricted intake, blocked exhaust???), or its comming from the breather pipe.....
The usage SEEMS to be (is) worse when high/sustained boost is used...I have no visable smoke, even after extensive idling either cold or after high speed runs
I have no noticable oil in the interooler (never god more than odd drips in the centre of the drain plug). Throttle body doesnt seem to get coated quickly either....
The plugs show no sign of excesive oiling...perhaps a little carboned, but dry and centers are fine....(car gets lots of short journeys...and lots of starts which could explain the plugs being slightly carboned)
The car runs well, and goes like a train....and returns about 22mpg...
Questions....
1. ANY suggestions
2. Could a partially blocked back box (muffler) cause this
3. The inlet under the wing to the airbox seems kind of restrictive to me...could it be to do with this intlet (e.g. is there anything there that could move providing a serious intake restriction?) - i have remove the trumpet restrictor from the intake....no change
4. If the oil IS comming from the breather tube (given that i have ok compression & -1" of vacume in tha crank at idle - measured down the dip stick tube) (a) why, (b) how can i PROVE it (c) this must need a SUBSTANTIAL air flow...where could the air be getting INTO the crankcase (assuming if it was blow by that bad i would (a) have smoke (b) not have good compression).
I would like to rig up some sort of secondary oil seperator box that i could MEASURE the oil level in - any ideas????
I have sort of run out of ideas on this one and after a yeara of trying am starting to wonder if it can be solved at all!
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