oil leak

joderest

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Hi all.
As some might remember I have oil leaking from the Turbo. I have nailed this down and it is coming from the compressor side of the turbo. It is not oil out of the turbo but oil going in.
It would appear after a lot of searching that the engine at 52,000 has a lot of crankcase compression, hence there is quite a lot of fumes at separator, as this cools goes back to oil which is taken into the turbo. There is quite a lot of oil in the pipes.
I do not think this warrants any engine work as car quite old.
Question
For the old school people on here, can I ask if fitting an oil catch can to catch the oil before the turbo would do the trick.
The leak is very small, about a teaspoon full in a 1000 miles or so, but would like to stop it if I can
 

oigle

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Yes, a catch can does work. What you are getting is common and not just in high mileage motors. All modern motors have PCV. Petrol engines just suck it into the inlet manifold whereas diesels, with little vacuum, have it fed into the inlet tract prior to the turbo. This the coats the whole inlet tract from turbo through intercooler and piping and then into inlet manifold where it combines beautifully with the egr input to create a lovely black tar. The oil itself does no damage but, combined with egr input, it causes heaps of problems. Either fit a catch tank or delete the egr.....

Ian.
 

Taffy7hfa

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IMG_1030egr1_zps6ros8tyz.jpg IMG_1033egr2_zpsydqy24r2.jpg
EGR's are a PITA, this is mine before and after.
 

Wighty

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The above was my catch can “story” on the om642 engine
 
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joderest

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Hmmm.
I want to reduce the oil going to turbo inlet. I have replaced the seperator which made no difference. The oil leaks out of rear of turbo, difficult to explain. If you consider there is a plate on the inside of the inlet side of turbo, it seems to me that the oil in the fumes collects inside and gets blown out, collects on bottom of turbo then drips on to the turbo activator, and then when there is enough drips onto the ground. It is very slight but would like to get rid of it.
May well just fit a catch can as I cannot see it will do any harm as long as its a closed system
 
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joderest

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I have ordered a cheap catch can to fit and see if it works. I read somewhere that an owner fitted one to a ML270 and it worked fine however he by passed the sensor in the line and his fuel consumption was lowered quite a bit.hence he removed the catch can.
I have worked out a way to keep the sensor in line, I have no idea what the sensor does or reads as its just fumes from the engine passing through it.
Located just after the oil separator in the pipe that joins to the air intake.
Out of curiosity does anyone know what it does.
 

Wighty

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I have ordered a cheap catch can to fit and see if it works. I read somewhere that an owner fitted one to a ML270 and it worked fine however he by passed the sensor in the line and his fuel consumption was lowered quite a bit.hence he removed the catch can.
I have worked out a way to keep the sensor in line, I have no idea what the sensor does or reads as its just fumes from the engine passing through it.
Located just after the oil separator in the pipe that joins to the air intake.
Out of curiosity does anyone know what it does.
You need a catch can that has large ports for a diesel , so many cans are designed for petrols . Maybe 1/2 inch plus , not sure if my old thread mentioned this
 
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joderest

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hmm.
no, but i have tried to match the size of the inlet/outlet to the same size as the pipe that attaches to the oil separator. Its only a cheap can, and if it works may invest in a better one, if it does not work i will return to standard, as if goes as planned will not destroy any pipes, fittings at all.
 
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joderest

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would still like to know what that sensor does that is part of the pipe that runs from oil separator to air inlet pipe, for the life of me i cannot think what it senses !!!!!
 
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joderest

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giving installation a bit of thought and have decided, as a trail to use clear plastic tube, like the stuff used on high pressure water pumps, reason ?.
I can then see how much oil is going to the catch can, and see how much is returning to the air intake, also its the only right size pipe i can find that will make up reducers so that it fits correctly !!!!.
It is oil resistant, and as it will be away from heat, should not get too soft.
 
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joderest

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OK, its in. All runs OK, no lights or issues. I will not use car until Saturday so will see how it goes.
Install comprised of a catch can, 2 metres of 1\2 inch bore clear plastic pipe, two copper right angle bends, which were used to get pipes going right way without tight bends. Two small jubelee clips.
Finding a place to mount can was a struggle, ended up next to the aux pump, as the bracket had a spare threaded mounting. The pipe from oil separator runs down hill.
I will report back at some point.
Oh, that sensor, I am told is not a sensor but a tiny heater, warms gasses going to turbo.
Well, that's what I was told.
 

Wighty

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OK, its in. All runs OK, no lights or issues. I will not use car until Saturday so will see how it goes.
Install comprised of a catch can, 2 metres of 1\2 inch bore clear plastic pipe, two copper right angle bends, which were used to get pipes going right way without tight bends. Two small jubelee clips.
Finding a place to mount can was a struggle, ended up next to the aux pump, as the bracket had a spare threaded mounting. The pipe from oil separator runs down hill.
I will report back at some point.
Oh, that sensor, I am told is not a sensor but a tiny heater, warms gasses going to turbo.
Well, that's what I was told.
Let’s have some pics buddy :D
 
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joderest

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I would but I struggle a bit with getting pictures on to the site.
Give me some time to figure it out
 
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joderest

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20191205_153805.jpg
 
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joderest

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20191205_153752.jpg
 
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joderest

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The pipes fitted very snugly into the copper elbows, but I super glued them as well. The other elbow was filed down a bit and it slotted neatly into the oil separator outlet, I just put a bit of sealent round it to be sure.
The system should be more air tight than it was before.

David Bailey I am not.
 
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joderest

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Maybe pictures in day light would be better. Now I have worked out how to do it with my phone I can post some better pics.
I am a tech idiot !!!!
 

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