300 Tdi Rebuild

This site contains affiliate links for which LandyZone may be compensated if you make a purchase.
julianf said:
Forgive me, as i have not read all of your thread, but i had an issue with oil comming from my 300tdi turbo, into the intercooler, and then the engine.

I tried the bottle trick, but the bottle was clean.
Swapped the turbo - still leaked.

Turned out the pipe from the base of the cyclone downward was blocked, so the engine was pressurising, and forcing oil through the (good) turbo seals.

I understand a blocked turbo drain can also do this, but, in my engines case, it was the cyclone hose.

Unblocked hose, and all was good.

Again, appologies if this i not 100% relevant - i have not read the previou 51 pages...
Click to expand...
Don't blame you not reading it! :)
That's interesting. What was blocking your pipe? I've got a new one on there, so it should be ok.
So, your blocked pipe was causing your oil pressure to go so high that the turbo seals couldn't hold it?
 
Yep.

After buying another turbo, changing it, and still getting the issue, i admitted my diagnostic skills being at their limit (this was after the bottle thing and all that - and cleaning out the intercooler no end of times) and took it to the garage round the corner.

As they knew id done all the previous stuff, they did not take long to find the engine was pressurising, and they cleaned out that drain pipe, and it was all good.

I changed the cyclone and the oil directly after as a precaution. I guess it must have been bits of the cyclone blocking the pipe? But i dont know.

Do check the turbo oil drain pipe too though, as i understand that can do the same.

Im still driving round with the replacement turbo on now - 450 miles this weekend alone. I saw no point in swapping them again, so i have my original as a spare now!
 
ps. why there wasnt oil shooting out the dipstick etc. i dont know

the garage said they took the filler cap off and that was when they realised the pressue, but i dont understand that either, but they said they unblocked that pipe at the bottom of the cyclone, and, whatever they did, it fixed it. This was last year somtime.
 
julianf said:
Yep.

After buying another turbo, changing it, and still getting the issue, i admitted my diagnostic skills being at their limit (this was after the bottle thing and all that - and cleaning out the intercooler no end of times) and took it to the garage round the corner.

As they knew id done all the previous stuff, they did not take long to find the engine was pressurising, and they cleaned out that drain pipe, and it was all good.

I changed the cyclone and the oil directly after as a precaution. I guess it must have been bits of the cyclone blocking the pipe? But i dont know.

Do check the turbo oil drain pipe too though, as i understand that can do the same.

Im still driving round with the replacement turbo on now - 450 miles this weekend alone. I saw no point in swapping them again, so i have my original as a spare now!
Click to expand...
Seems strange. Was it not the pipe coming up from the crankcase to the top of the cylinder head?
 
That would make more sense.

I did query the diagnosis at the time, and the chap, in the nicest way, kind of shrugged his shoulders, and reiterated that the issue was fixed. Possible the wrong hose was communicated to me, possibly it wasn't, but, like the garage chap said, it was fixed, so it wasn't worth ME pressing the issue.

My advice to you, as a result, may or may not be inacurate, however, the concept is there, even it it might be a different breather! : )
 
julianf said:
That would make more sense.

I did query the diagnosis at the time, and the chap, in the nicest way, kind of shrugged his shoulders, and reiterated that the issue was fixed. Possible the wrong hose was communicated to me, possibly it wasn't, but, like the garage chap said, it was fixed, so it wasn't worth ME pressing the issue.

My advice to you, as a result, may or may not be inacurate, however, the concept is there, even it it might be a different breather! : )
Click to expand...
Absolutely, I'll investigate all breathing pipes. Cheers.
 
He certainly said to me that he took off the filler cap, and there was pressure there, so that might be simple test.
Id think that taking out the dipstick would test for pressure in the lower half.

If both are at atmospheric (so no hiss from either) id assume, unfortunately, its something else.... : (


When i was doing no end of test drives to figure ours out, i never got to the bottom of exactly the driving style to trigger it. I guess any reaction would be delayed by the oil working its way through the intercooler anyhow.

It was a pretty hateful time. I drove the car to pick up the replacement turbo, keeping the revs right down, but waiting the whole way for a run-away condition.
 
julianf said:
He certainly said to me that he took off the filler cap, and there was pressure there, so that might be simple test.
Id think that taking out the dipstick would test for pressure in the lower half.

If both are at atmospheric (so no hiss from either) id assume, unfortunately, its something else.... : (


When i was doing no end of test drives to figure ours out, i never got to the bottom of exactly the driving style to trigger it. I guess any reaction would be delayed by the oil working its way through the intercooler anyhow.

It was a pretty hateful time. I drove the car to pick up the replacement turbo, keeping the revs right down, but waiting the whole way for a run-away condition.
Click to expand...
I'll do some more tests this weekend. Focusing more on pressure than the passage of oil. If I take the return pipe off the bottom of the cyclone I can put a catch bottle under the cyclone unit. The top, open end of that pipe should release any pressure in the sump. I can then check oil leakage in to the turbo outlet pipe again.

In the meantime I've been in touch with the company I bought the turbo from. They've been very good throughout. The Mrs has some time off work in three weeks time, so they are going to pick the turbo up then and check it out. They said they didn't have one on the shelf to swap, but rather than me do any further work on the engine they would look at it to check it out. More convenient for us when the Mrs isn't at work as it's her daily drive, so that's in three weeks time. :)
 
Must admit I cant see how a blocked cyclone (or pipe) can cause an increase in oil pressure to the turbo to the point that it will force oil out passed the seals. The turbo should be able to contain its oil at full oil pressure (55 PSIG), any higher pressure than that should cause the relief valve to open. Not saying that what JF said wasn't what he was told at the end of the day the fault was fixed but I would suspect the blocked breather pipe would have caused the engine to smoke because oily air was being ingested by the turbo rather than oil escaping out of the turbo body.o_O.
 
Kwakerman said:
Must admit I cant see how a blocked cyclone (or pipe) can cause an increase in oil pressure to the turbo to the point that it will force oil out passed the seals. The turbo should be able to contain its oil at full oil pressure (55 PSIG), any higher pressure than that should cause the relief valve to open. Not saying that what JF said wasn't what he was told at the end of the day the fault was fixed but I would suspect the blocked breather pipe would have caused the engine to smoke because oily air was being ingested by the turbo rather than oil escaping out of the turbo body.o_O.
Click to expand...
Yes, I agree but I'm happy to try anything. I had a similar conversation with the turbo company who suggested a possible blocked return from the turbo. I was questioning how the turbo seals wouldn't be able to cope with the pressure. What I don't know is if overly high pressure in the turbo feed pipe would create pressure back to the relief valve enough for it to open.
 
Al2O3 said:
Yes, I agree but I'm happy to try anything. I had a similar conversation with the turbo company who suggested a possible blocked return from the turbo. I was questioning how the turbo seals wouldn't be able to cope with the pressure. What I don't know is if overly high pressure in the turbo feed pipe would create pressure back to the relief valve enough for it to open.
Click to expand...
I'd be surprised if the oil return pipe could be blocked unless it had been really twisted during installation and that should be easy to spot. It is a relatively large diameter pipe, is very short and just dumps its contents into the sump IIRC.
 
Kwakerman said:
I'd be surprised if the oil return pipe could be blocked unless it had been really twisted during installation and that should be easy to spot. It is a relatively large diameter pipe, is very short and just dumps its contents into the sump IIRC.
Click to expand...
A perfect description.
This is me proving mine is not bent, kinked or blocked. :)
Checking return pipe.JPG
 
Magicgrotto said:
You did remember to take the bung out of the turbo before you fitted it ?:rolleyes::rolleyes:
Click to expand...
Even though I had fitted the feed pipe, then the return pipe, turned the engine over (no fuel supply) several times with the return pipe in a milk carton to catch the oil, with oil flowing well. I have been back and checked that I hadn't left the bungs in! :eek: Mad, but I did check again. :rolleyes: Worth a shout, cheers.
 
Al2O3 said:
The thought of getting the compressor out has crossed my mind.
Click to expand...
Just blew down the pipe instead. :) Took the pipe off the bottom of the cyclone and blew down it. Could hear the air bubbling through the oil in the sump. Wasn't expecting that! No blockage though.
 
You must log in or register to reply here.

Similar threads

P
Clutch stuck 300 tdi
Replies
13
Views
571
portokali
P
G
Diagnosing black smoke under load on 300tdi?
Replies
3
Views
353
D1Nut
D1Nut
G
Land Rover 300tdi clutch not disengaging after engine out
Replies
8
Views
1K
miktdish
miktdish
currymunster
I suffered a Run away diesel
3 4 5
Replies
85
Views
7K
currymunster
currymunster
Ian Whitewick
Defender 200tdi refresh
Replies
1
Views
432
steve2286w
steve2286w
Back
Top