I'm going to take the turbo oil outlet pipe off tomorrow. It looks fine from the outside, but maybe it's collapsed inside. If it's restricted somehow it would presumably cause back pressure and maybe lead to some oil being forced through the turbo rings? Fingers crossed there's something wrong with it! :eek::mad:

It could be a delamination, so the layer is sucked down under load, might not be obvious ...
 
It could be a delamination, so the layer is sucked down under load, might not be obvious ...
Yeah, I've got my fingers crossed it's something like that. I've ordered a replacement, but given the time of year it's going to take a while.
 
When you did the rebuild was oil pump, relief valve checked / serviced?
Thinking excess pressure on oil, not sure if you have pressure gauge this post has been running so long.
 
I still think this has something to do with the temperature of the oil.
Too hot and it darkens quicker and degrades towards the nominal number of oil your using i.e 10w40 will degrade to SAE 10.
Engine oil when too hot thins out, made worse with the above and passes through the seals.
 
When you did the rebuild was oil pump, relief valve checked / serviced?
Thinking excess pressure on oil, not sure if you have pressure gauge this post has been running so long.
Yes, I replaced the oil pump, although it's more of a gear in the 300Tdi. The relief valve spring was replaced too. I've got an oil pressure gauge fitted. It's about 4 bar when cold. Drops to about 2.7 bar when hot. Aye, this post has been running for a long time. I'm looking forward to it finishing!
 
I still think this has something to do with the temperature of the oil.
Too hot and it darkens quicker and degrades towards the nominal number of oil your using i.e 10w40 will degrade to SAE 10.
Engine oil when too hot thins out, made worse with the above and passes through the seals.
So do you think the new radiator/oil cooler isn't working?
 
I have no idea Al. It makes sense to me that the problem is oil getting too hot.

The oil blackened quickly and oil passes the turbo, even a spanking new one from Turners so it's got to be the oil overheating.

Could be a lot of things not just the rad.
Is your dipstick reading correctly, cos if the oil level is too high the crankshaft could bash the oil and overheat and foam it, reducing oil pressure at the same time.
Oil filter housing thermostat as mentioned before
Oil blockage
Wrong oil
and god knows what else

I'm not a mechanic. So you understand, so what I'm saying might be completely laughable but it does make sense.
You've done more or less everything anyone could think of to alleviate the problem.

Measuring oil temp might be a ballache to sort out though

Unless your incredibly unlucky !
 
I have no idea Al. It makes sense to me that the problem is oil getting too hot.

The oil blackened quickly and oil passes the turbo, even a spanking new one from Turners so it's got to be the oil overheating.

Could be a lot of things not just the rad.
Is your dipstick reading correctly, cos if the oil level is too high the crankshaft could bash the oil and overheat and foam it, reducing oil pressure at the same time.
Oil filter housing thermostat as mentioned before
Oil blockage
Wrong oil
and god knows what else

I'm not a mechanic. So you understand, so what I'm saying might be completely laughable but it does make sense.
You've done more or less everything anyone could think of to alleviate the problem.

Measuring oil temp might be a ballache to sort out though

Unless your incredibly unlucky !
It's a good theory. The water temp gauge doesn't get high. I've no idea if the oil passing through the radiator can avoid being cooled while the water is?
I've forgotten about the oil filter thermostat!!!! Feck!!!
The dipstick is reading ok.
 
It's a good theory. The water temp gauge doesn't get high. I've no idea if the oil passing through the radiator can avoid being cooled while the water is?
I've forgotten about the oil filter thermostat!!!! Feck!!!
The dipstick is reading ok.
Is the dipstick tube slipped ? Wrong dipstick ?that kinda thing i was referring to, which can say full on dipstick but be 2 pints over or something drastic like that
 
Is the dipstick tube slipped ? Wrong dipstick ?that kinda thing i was referring to, which can say full on dipstick but be 2 pints over or something drastic like that
Same dipstick set up I've always had for 15 years. I know from servicing over that time how 6.5 litres of oil sits on the dipstick.
I'm busy on the Turners website looking for the oil thermostat!
 
I've taken the oil thermostat out this afternoon.
Cleaned it up and tested it.

Didn't have to warm it for long and it opened up. Obviously, I was hoping it wouldn't. :(
On refitting the thermostat and it's spring back in to the housing I realised how strong the spring is, so I suppose there is a slim chance that the stat might be able to open, but is no longer strong enough to open against the spring? Think I'm clutching at straws there. :rolleyes:
The spring was that strong I couldn't push the housing down on the spring and get the bolt in at the same time. Space is tight/awkward, so used a spanner up against the inner wing to compress the spring and hold the housing in far enough to get a few threads on the bolt started.
oil thermostat.JPG

An aftermarket stat is about £6 and an OEM one about £40 I might as well order an OEM one and fit it after new year.
 
I've taken the oil thermostat out this afternoon.
Cleaned it up and tested it.

Didn't have to warm it for long and it opened up. Obviously, I was hoping it wouldn't. :(
On refitting the thermostat and it's spring back in to the housing I realised how strong the spring is, so I suppose there is a slim chance that the stat might be able to open, but is no longer strong enough to open against the spring? Think I'm clutching at straws there. :rolleyes:
The spring was that strong I couldn't push the housing down on the spring and get the bolt in at the same time. Space is tight/awkward, so used a spanner up against the inner wing to compress the spring and hold the housing in far enough to get a few threads on the bolt started.
View attachment 196840
An aftermarket stat is about £6 and an OEM one about £40 I might as well order an OEM one and fit it after new year.

Would be a nice Christmas present if it sorted things out.
 
Would be a nice Christmas present if it sorted things out.
I got my hopes up with the stat, but it's not looking likely.
I've got a new turbo oil outlet pipe on it's way. Reckon it'll be here by the weekend or Monday. It's such a short, thick pipe I'll be surprised if it's collapsed inside, but you have to hope! :rolleyes:
 
Not cured yet, but I'm making some progress.
I decided to order a new turbo oil outlet pipe and it arrived today.
Here's the old and new together.
new pipe.JPG

On the face of it the old one looks ok. However, I decided to cut one end off.
This is what I found.
old pipe kinked.JPG

Thought I was on to a winner so set about fitting the new pipe. Finger tightened the bolts on the turbo end and this is where the block end of the pipe lined up.
misaligned.JPG

I had to force it across to get the pipe on to the connector. Tightened everything up and then lay underneath to see how it looked.
new pipe kinked.JPG

An obvious kink in the pipe! :eek::eek::eek::eek::eek:
I was losing light so decided to just take the new pipe off for now.
So, since the engine rebuild, the turbo oil outlet pipe does not line up with it's connection on the block! :confused:
I can only think that I have put the two outer exhaust pipes on the wrong sides of the turbo? If the shorter pipe was on the bulkhead side of the turbo that would move the turbo back an inch or so. I would have thought that the central bolts from the head to the turbo wouldn't then line up? I'll find out when I take it off in the morning.
Any other ideas as to what else I could have done wrong?
 
An obvious kink in the pipe!

You might be able to release that kink by turning the swages on the fittings really carefully.... IIRC, it's pretty low pressure coming out of the turbo, so one can only hope it doesn't leak afterwards......

You could practice on your old (scrap) pipe first....
 
You might be able to release that kink by turning the swages on the fittings really carefully.... IIRC, it's pretty low pressure coming out of the turbo, so one can only hope it doesn't leak afterwards......

You could practice on your old (scrap) pipe first....
Do you not think the turbo is misaligned?
The old pipe obviously fitted ok once before, but has ended up kinking when being fitted after the engine rebuild. It's as though it doesn't line up any more? You can't get a good view of that pipe from above and I've been focussed on a turbo fault or honing fault up to now, not a restriction in the outflow pipe. Now that I'm looking at the pipe it does seem misaligned. Don't know how though :confused:
I'm off to google what the exhaust manifold set up should look like. :rolleyes:
 

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