oil in intake hoses???

[haven]

pulled apart my intake hoses and air filter box today and there's heaps of oil in the pipes....
would this most likely be caused by blown turbo seals??
anyone know someone who sells or where i can get new turbo seals to rebuild it or is it easier to just get a replacement turbo?

cheers

[steveNZ]

Hi
if its the turbo seals then the oil will only be after the turbo, if the oil is before then it sounds like blow by causing it a catch can might help, also if your air filter is blocked it will cause the engine to suck air from the breather also sucking oil in
have a look at this thread viewtopic.php?f=19&t=1439
and theirs other threads regarding catch cans and blow by on forum
hope it helps

Steve

[haven]

yea thats what i got confused about..does blow a little bit of smoke but nothing substancial. significant volumes of oil are produced in the intake hoses though over short periods of time...

thanks for the link, however other than a catch can suggestion im very confused as to what the actual cause is?
whats the main cause of excessive blow by on these engines?

[steveNZ]

Blow by which is caused by exhaust gasses from the combustion chamber getting forced past the piston rings or a valve that is not seated correctly

Unless your air filter is blocked up causing it to suck to much air from the rocker cover or there's a problem with the breather diaphragm in top of rocker then it has to be blow by
This causes excess pressure in the crank case witch intern forces its way up to the rocker cover dragging oil out with it through the breather
i get the impression that most isuzu diesel engines have a habit of producing blow by witch is ok up to a certain level

As i have just discovered if the blow by is to great and a catch can is not preventing the oil from getting into air system then it looks like your rings are worn out

I would get a new air filter and check breather diaphragm first ,then a catch can if problem continues, worst scenario is rings
hope it helps

Steve

[ftomas]

Blow by which is caused by exhaust gasses from the combustion chamber getting forced past the piston rings or a valve that is not seated correctly

Unless your air filter is blocked up causing it to suck to much air from the rocker cover or there's a problem with the breather diaphragm in top of rocker then it has to be blow by
This causes excess pressure in the crank case witch intern forces its way up to the rocker cover dragging oil out with it through the breather
i get the impression that most isuzu diesel engines have a habit of producing blow by witch is ok up to a certain level

As i have just discovered if the blow by is to great and a catch can is not preventing the oil from getting into air system then it looks like your rings are worn out

I would get a new air filter and check breather diaphragm first ,then a catch can if problem continues, worst scenario is rings
hope it helps

Steve

Where is the breather diaphagm?? do you have an photo of it?

[bellavesus]

breather diagram, is located on the top of the valve cover, towards the rear. it has 4 screws holding it down. im trying to toubleshoot my own 4jb1t that is breathing real heavy as well- i am wondering if the vent cap is to blame.

[ftomas]

breather diagram, is located on the top of the valve cover, towards the rear. it has 4 screws holding it down. im trying to toubleshoot my own 4jb1t that is breathing real heavy as well- i am wondering if the vent cap is to blame.

Sorry but i can see.... it's inside the valve cover?

[bellavesus]

no .not in, its on the top. at least on mine its on top of the valve cover, right about under that pipe on yours that runs across the engine in the back there beyond the intake manifold. yours may not have it, i cannot see it in the picture. i have the intercooler on top, so its easier to see. if you look on my post "2.8 breathing heavy" i think i posted a photo of the top of the engine where i mounted an oil catch can.

[ajaravani]

I have also having the same problem on my Isuzu KB 280 DT 97 model. I bought a new breather diaphram from Isuzu but this did not fix my problem. I have disconnested my breather pipefrom the intake into a bottle, and a lot of oil is being collected in the bottle. It looks like this is also affecting my turbo now as I had to change 2 turbo's due to the same problem, with the beather pipe not connected I connected a brand new turbo which ran for a few days without any signs of oil in the turbo and after the turbo, but yesterday just noticed some oil coming out of the turbo into theintake manifold, now I am assuming my sump is being presurised and the turbo oil return pipe is being presurised hence the turbo getting a lot of pressure as well. I think the next step are the rings.

[jackmech2]

Can I just ask what the role of the breather diaphram is, I always thought is was supposed to automatically close or at least restrict breathing when at very high/full revs to stop the turbo sucking oil into it's self.
Is this near the truth, or am I just making things up?
I only thought this cus I had a diaphram go on a turbo diesel car, and at near full revs it belched out black smoke, but once a new one was fitted it never did it again.....

[Smurt2010]

Hi guys just wondering what causes a Holden tf 1999 rodeo 4jb1t Diesel engine to rev really high while driving making a loud shutter sort of noise in direction of Injector pump causing engine to hiccup and then blow a big puff of black smoke from exhaust
Thanks for your help