Peter S30 Apr 30, 2014 12:02 pm
Subject: oil suction mesh

The engine of my new 2ltr has received a modern oil filter by a previous owner. I was going to change oil and filter and also removed the suction side tube in the sump in order to clean it, expecting some sort of mesh here. But the tube was empty and what also surprises me that it only has the one rather small hole to let oil in (about 1/2" or 10-12mm). How was that orginally?

I could try to put some mesh or wedge-wire filter in but if it is to fine it creates much undesired pressure drop on the suction side of the pump with cold oil and if it is to coarse it is useless.

And I really wonder why there is only this one hole for the oil to enter this big tube, any reason not to have more holes?
Attachments:
suction tube-kl.jpg (Filesize: 59.71 KB)

Peter S30 May 20, 2014 11:16 am
Subject: Re: oil suction mesh

I have put it back in without mesh so far. I increased that one hole by about 2mm in diameter, then it is about the inner diameter of the suction tube to the oil pump. I asked a company for a quote for a custom built metal edge filter tube (as an alternative to a simple mesh) with 0.2mm gap (as an example), this would cost 135 EUR per piece when ordering 3, quite reasonable price. But finally I decided it worked well before without and I might improve for the worse. At the moment I have to reduce the spring of the oil pressure relieve walve a bit (pressure cold with a 20/50 oil is 55psi and when hot in fast idle above 40)