Thread: Smoking exhaust and high oil pressure

Stuck relief valve?

What are you using to measure the oil pressure? Could the gauge be affected by voltage or anything else?

There are 2 pressure relief valves in the lubrication system.

The 1st is in the body of the lubrication pump and should open at about 100 psi.

The second is in the main oil gallery and should open at about 43 psi. This screws into the right side of the block, under the oil cooler. You may not see it because it would be alongside the governor on the fuel injection pump.

It screws upward at an angle, so it may be possible to access without removing the injection pump - I'm not sure and don't have time to go and look now.

The body is quite large possibly about 40mm, but it has a smaller hexagon maybe 12mm AF for a spanner in the centre of the large flange. Parallel thread and O-ring seals. This relief valve is one of the items usually replaced when a 4BD1 engine is overhauled.

There are bypass relief valves in the oil filter and oil cooler, so lubrication still happens in case those items become blocked.

I would say your problem is the main relief valve in the oil gallery.

Originally Posted by flagg

What are you using to measure the oil pressure? Could the gauge be affected by voltage or anything else?

Nope, used two gauges, both giving the same reading. Will change out the filter again and take a look at the pressure relief valve. All being good, my next thread will be along the lines of "on the road again" :-)

Prior to removing the motor, oil pressure was good. What have you been touching mike
This may be contributing to your Turbo problem me thinks

Originally Posted by Vern

Prior to removing the motor, oil pressure was good. What have you been touching mike
This may be contributing to your Turbo problem me thinks

Nothing, as you saw, on the main block. Engine came out of Rangie, engine went into Defender. Only thing I did was change the oil and the filter.

Is there oil still backing up from the oil dump pipe from the turbo?

The relief valve ( the one under the IP ) would be the next thing to look at.

Then check to see if you have fitted the correct oil filter for that engine.
.

Swopped out the filter as a precaution, and plumbed in a good old fashioned mechanical gauge temporarily to eliminate electric key. Mechanical gauge is reading a nice 55-60 psi, which is obviously in far more acceptable territory. Must be a bum sender?

Now to let all the smoke out of it..... :-P