Oil pressure

[jack_aubrey]

Hi

I bought an '82 Volvo DL diesel wagon not that long ago, and recently the oil pressure warning light came on and stayed lit whenever the engine was on. I swapped the sender units to no effect, so I ran the engine for about 30 seconds with the sender unit and valve cover off the engine, and no oil emerged. So, I removed the engine from the car to check the oil pump. When I removed the pump, everything about it seemed to be in perfect working order, other than a spring-loaded tube on the right side of the pump which seemed to be stuck halfway open (first picture) (where exactly does this lead to?). After prying on it a bit, it opened all the way and then closed fully (second picture). The other possibility is that there's something stuck in one of the oilways; how would I go about testing this? Also, I hadn't driven the car enough to change the oil, so I'm not sure how long it's been since an oil filter change, but the oil pan did not have any sludge or chunks in it. Could the filter simply have been clogged enough to cause the oil pressure light to come on (or would an oil-soaked filter always block blown air, regardless of being clogged?), or is the stuck valve in the oil pump more likely the culprit and if so, how would I ensure that it was fixed?

[piper109]

What you are showing are pics of the pressure relief valve. This valve opens to limit oil pressure and the strength of the spring detemines how high the pressure goes.
If it was stuck in the open position, it would vent the oil to the pan without it circulating though I have a hard time believing that could happen. You could polish the spool with crocus cloth to prevent it from sticking and make sure it is free to move in its bore.
Pack the pump with grease before you reassemble as this will enable the pump to prime itself quicker.
You can temporarily remove the oil pressure switch while cranking to see if oil is circulating.

Steve

[jack_aubrey]

Thanks for the quick reply! I took the valve apart and cleaned it as best I could, but I thought of another question: would it be more advisable to clean the valve and put it back together, or is this a problem that once it arises, will happen again, in which case should I just replace the entire pump? Could this be a problem with the spring wearing out, and if so, does anyone know the specs on the spring or where to find a replacement? On that note, I am having a devilishly hard time finding anyone advertising parts for this particular engine (NA D24, vintage 1982), including the oil pump--I wanted to replace all the rubber on the engine as long as I had it out of the car, but no one seems to have even something as simple as coolant hoses and timing belts. Does anyone know who stocks parts for this engine, and also what parts might be compatible with other models?

[piper109]

I have never heard of one of those valves sticking before as the spring tries to return it. I would definately polish the spool and polish the bore too. Use very fine emory !! Wrap it around a dowel to clean the bore.
If it moves freely by finger, it should move freely by oil pressure.

The spring strength controls oil pressure so you dont want to touch that spring except to replace it with a new one of the same.

The same oil pump is used on the VW D20 engine which was used in Audi 5000 of the same period and of course the D24 variants.

Check on Ebay for Volvo diesel and Audi diesel parts and you will find stuff for these engines amongst the other stuff. Bear in mind that some parts are in common with 4 cyl VW diesels but only a limited amount.

Steve

[MRDART]

A friend of mine had a chrysler something v8 engine in his willys hotrod that had the same problem, but it was really easy for him to find new parts...

[j_lepe]

Hello D24 Gurus.
I have a problem with the oil pressure of my volvo 240 from 87, since it starts it goes to the maximum 5Bar/75PSI. I have changed the sensor and it is still the same, the pressure is real. I think the motor is very noisy for this reason, any advice?