Hi All
I've got a 1986 UK T25 1.6TD that recently (150 miles ago) had a reconditioned engine fitted. The replacement engine was fitted due to ongoing overheating problems with the original engine that were never solved.
The good news is that the overheating problem has now gone away, but a new problem has surfaced with the reconditioned engine whereby the engine dumps most of its oil when operating under load.
I had a recent incident where, going uphill, the oil light came on and then the engine cut out almost immediately. Upon inspection I found that oil had been sprayed all over the engine bay (making tracking the source of the leak impossible) and the sump was completely empty. Fortunately it appears that no detectable damage has been done as the engine still runs and sounds fine, but I'm now loathe to use the vehicle until the problem has been sorted. Even after this incident the engine does not leak oil when idling or when revved when under no load.
I'm thinking along the lines of excessive oil pressure, perhaps due to a sticking relief valve, but I'm not yet familiar enough with this type of engine to accurately diagnose the problem.
Can anyone shed any light on a possible cause?
Thanks
Chris
1.6TD T25 Engine Dumping Oil Under Load
Moderator: Fatmobile
I'd guess its blowby.
Due to worn rings or oil thinned from overheating.
Air/fuel blows by the rings on the compression/power rev. The rings are sealed the rest of the time, which turns your crankcase into an air pump. The oil spews from every seal. Also, because its air and fuel blowing into your crankcase, you might end up with diesel in your oil, too. This will serve to thin out the oil, making the problem potentially worse over time.
Just a possibility.
My first guess would have been the PCV valve, too, but I don't think this engine has one.
Due to worn rings or oil thinned from overheating.
Air/fuel blows by the rings on the compression/power rev. The rings are sealed the rest of the time, which turns your crankcase into an air pump. The oil spews from every seal. Also, because its air and fuel blowing into your crankcase, you might end up with diesel in your oil, too. This will serve to thin out the oil, making the problem potentially worse over time.
Just a possibility.
My first guess would have been the PCV valve, too, but I don't think this engine has one.
Michael Curtiss
1982 Vanagon L - 1.6L NA Diesel, 4spd
1996 Passat Wagon - 1.9L TDI (1Z), 5spd
1982 Vanagon L - 1.6L NA Diesel, 4spd
1996 Passat Wagon - 1.9L TDI (1Z), 5spd
Hi Michael
Thanks for your reply.
The engine that's currently fitted was supplied by a reconditioning firm and now has done only 125 miles since being fitted, so I hope that the bores and rings are all in good condition.
Interesting that you should mention the PCV valve. The van's just come back from my mechanic with the problem seemingly resolved. He replaced a valve that fits into the inlet manifold, the other end attaches to the breather pipe that connects to the valve cover.
I didn't ask him for details of his diagnosis, but do you think it's possible that the valve had failed and stuck open, causing pressure from the turbo to enter the crankcase via the breather pipe?
Cheers
Chris
Thanks for your reply.
The engine that's currently fitted was supplied by a reconditioning firm and now has done only 125 miles since being fitted, so I hope that the bores and rings are all in good condition.
Interesting that you should mention the PCV valve. The van's just come back from my mechanic with the problem seemingly resolved. He replaced a valve that fits into the inlet manifold, the other end attaches to the breather pipe that connects to the valve cover.
I didn't ask him for details of his diagnosis, but do you think it's possible that the valve had failed and stuck open, causing pressure from the turbo to enter the crankcase via the breather pipe?
Cheers
Chris
