That's the bit I didn't get. I can see what you're saying now.Sorry maybe I didn't put that very well, the boost pressure is controlled by opening up a gate or valve when boost is too high, this will allow the exhaust gasses to divert and reduce the flow through the turbo, this has the effect of reducing the power of the turbine and it slows down therefore the flow falls on the delivery side, if this is done smoothly then the pressure curve will just flatten out, if it too violent then the pressure will collapse and this would shut the exhaust bypass bringing the turbo up again rapidly.
The effect would be flow,and the pressure in the volut going up and down.
It's just a thought to investigate, because you seem to have followed so many other Avenues.
We sometimes saw compressors left unloaded for long periods would pull the oil through the carbon seals, when the seals became oily then the oil would burn in the small gap between the car and the shaft and it would become sticky.
Good picture! Yeah, I know the basics of how the turbo works. It was the bit about the pressure curve I found a bit vague in your first post about itYou probably have spent more time on this than most people but the TD5 setup looks like this.
The actuator is controlled by the discharge air pressure
View attachment 209809
May be miles off, but its difficult to try and think of something you haven't already covered, you must be getting a bit frustrated by now.Good picture! Yeah, I know the basics of how the turbo works. It was the bit about the pressure curve I found a bit vague in your first post about it
Yeah, I know. It's becoming a living pain in the backside.@Al2O3 , at this stage I think the only outstanding variable is oil weight.
I'm sure the 300Tdi wouldn't be too bothered running on some SAE50 oil with summer coming, just to see if it puts a cap on your oil consumption.
To be honest, saw your latest update from yesterday and went like, "oh crap, still??"
Certainly am!May be miles off, but its difficult to try and think of something you haven't already covered, you must be getting a bit frustrated by now.
Hello neilly!Silly Question time,
are you sure it is oil, and not diesel ?
Cheers
Hello neilly!
I think that is a very interesting question. Because, when I start her up, especially when hot, I get a small puff of black smoke.
However, the oil level goes down and if I take the turbo outlet pipe off, the inner wing gets sprayed with oil!
So, maybe a few things going on, but the turbo passing oil is the priority at the mo.
Certainly have, it's a buggerOK, still sounds like you have the old oil passing issue.
Cheers
Certainly have, it's a bugger
Yes, I have entertained such thoughts. I suppose it's difficult to admit you've rebuilt a sh@t engineNow, I know you are invested in the rebuild and the multiple turbos etc. But have you thought about getting another 300tdi engine to replace it? then you could look in depth at what could be the problem and break it down piece by piece.
Cheers
Yes, I have entertained such thoughts. I suppose it's difficult to admit you've rebuilt a sh@t engine
I know JM is convinced it's the honing of the bores, but I'm not so sure. The turbo is certainly passing oil and, I think, it's responsible for all of the oil consumption. JM is usually right though, so my rebuilt engine is probably sh@gged
No, right from the start of the oil consumption JM said honing. However, I've bypassed the turbo once already and it was pi$$ing oil out on to the inner wing. So, despite JM's summation, I'm pinning my hopes on knackered turbos. knackered by a kink in the oil outlet pipe causing back pressure and the HP oil feed forcing oil through the ring seals.I know it would be a PITA, but it would give you options. At least you could rehone the cylinders, I thought when you did them JM said they were good??
Plus you could try the new turbo on the other engine, I Understand as a retiree it would give you something to do...LOL.
Cheers
How would you test it accurately? Buy a pressure gauge?Whats the Crankcase pressure like?
Considering the fact it's gone through a few turbo's all with the same issue, and associated pipework, excessive pressure will affect the oil feed to the turbo and acts as a restriction to the oil feed pipe, which can cause oil to leak either into the Compressor/turbine.
Personally i'd pull that engine instead of spending too much more on it..
Easiest way is to pop the oil cap off when it's running..How would you test it accurately? Buy a pressure gauge?
Yeah, I've already done that, Henry. All seems fine.Easiest way is to pop the oil cap off when it's running..
If it chuffs like a steam train then expect excessive blowby/crankcase pressure.
Also you can rest the oil cap over the hole, and if it tries to fly off, then that's part of your issue.
When I rebuilt my engine I took off the oil breather and put my hand over it just to see how quickly it built up, second time I did it it blew the plastic cam shaft seal out with a whoosh.Easiest way is to pop the oil cap off when it's running..
If it chuffs like a steam train then expect excessive blowby/crankcase pressure.
Also you can rest the oil cap over the hole, and if it tries to fly off, then that's part of your issue.