Thread: Td5 Blowby, Okay or too much?

Hi. That seems too much to me, make sure that the depression control valve is not stuck closed cos it should be open at idle and release pressure into the intake... to check it undo it from the intake and see what comes out of it then remove it from the breather pipe and compare

Originally Posted by sierrafery

Hi. That seems too much to me, make sure that the depression control valve is not stuck closed cos it should be open at idle and release pressure into the intake... to check it undo it from the intake and see what comes out of it then remove it from the breather pipe and compare

I ran the engine with the breather pipe disconnected from the rocker cover with no real difference.
Possible case of worn rings?

It exceeds my knowledge what would cause that but i know that on my D2 at 310K Km less pressure is coming out there... thinking twice simply undoing the breather pipe might not help too much cos while it's connected there is a suction in it from the intake which would reduce the pressure... blow gently through the depression valve to make sure it's not blocked... if you remove the breather pipe with oil cap tightened do you see the same pressure there?

I will try and double check that in the morning but from memory I did screw the oil fill cap on while the crank breather pipe was off and a decent amount, similar to the video came out. I’ve been meaning to check the depression valve so will report back what I find.
For curiosity sake, if it were worn rings, would that be something to fix ASAP or just keep her topped up with oil and drive it?

I'm not the man to answer to that but i made a video for you from mine to give you something to compare with(the engine was not up to temp, i let it idle with the FBH on for about 10 minutes)... so i'd say that if mine is OK then your's is not:

YouTube

maybe somebody smarter with engine issues will help but IMO that oily crankcase gas going through the intercooler is not too good.

How hot was the engine when you did the video?

I've got one that blows like that as well, it's definitely got some wear, as to how much of a problem it is..... I guess if power and fuel mileage are ok and it starts fine I wouldn't be too concerned at this stage.

I would however be fitting a provent style catch can pronto, because as pointed out, that will be making your intercooler and intake system filthy.

Cheers
James

Originally Posted by shack

How hot was the engine when you did the video?

I've got one that blows like that as well, it's definitely got some wear, as to how much of a problem it is..... I guess if power and fuel mileage are ok and it starts fine I wouldn't be too concerned at this stage.

I would however be fitting a provent style catch can pronto, because as pointed out, that will be making your intercooler and intake system filthy.

Cheers
James

It was up to operating temp as I’d just been for a drive, when it’s cold there’s no pressure at all coming from the crank - I had heard that is normal but not sure how that works as you’d think with the engine cold and everything not expanded there would be more but maybe someone could answer that.
It’s already got a flashlube catch can fitted which definitely catches a lot.
Thanks

I thought that maybe mine wasnt hot enough so i was curious and checked after i came home from work with engine up to temp and it was the same like in my video