Page 1 of 1

Oil prerssure

Posted: Sun Jan 13, 2019 11:24 pm
by housebg
Just rebuilt a 885 David Brown and now cannot get any oil pressure or flow even to oil filter. Pulled the tractor to try to get the oil Pressure up and nothing .The tractor was apart when we started .Where is the oil bypass valve could it be stuck. Any one with a oil flow diagram a copy would be helpful.Billy

Re: Oil prerssure

Posted: Mon Jan 14, 2019 5:11 am
by cobbadog
On the 30C engine it is on the filter housing. But check that you have not fitted the gaket behind the housing on back to front. Are you getting pressure anywhere?

Re: Oil prerssure

Posted: Mon Jan 14, 2019 5:35 am
by ollek
The following is a link to the parts catalogue https://partstore.caseih.com/us/parts-s ... 83ar755888 As you can see, the by-pass valve is in the pump cover, not in the filter housing.

Re: Oil prerssure

Posted: Mon Jan 14, 2019 7:38 am
by db2d
The filtering system on an 885 is totally different from a 30C. The gasket mentioned does not exist.

Re: Oil prerssure

Posted: Mon Jan 14, 2019 10:11 am
by ollek
And the following link shows that there is no separate filter housing on a 885 engine, the filter fits straight into the machined face of the engine block. https://partstore.caseih.com/us/parts-s ... 7ar1264045

Re: Oil prerssure

Posted: Mon Jan 14, 2019 10:50 am
by philedge
The OP asked where is the bypass valve and as far as I know, as cobbadog said, the bypass valve is in the filter housing, item 22 in the linked parts drawing.

Re: Oil prerssure

Posted: Mon Jan 14, 2019 11:06 am
by ollek
The question asked by the OP can be a little bit misleading and the answers are therefor not correct. The pressure relief valve can be stuck, not the filter by pass valve, if there is no oil pressure. The filter by pass valve has nothing to do with the engine oil pressure. The problem is most likely in the pump, feed pipe from the pump to the cylinder block or the pressure relief valve if, as the OP says, no oil is present at the filter. The problem can also be damaged drive gears at the pump or the cam shaft.

Re: Oil prerssure

Posted: Mon Jan 14, 2019 2:45 pm
by housebg
Thanks to all will start and go from there Billy

Re: Oil prerssure

Posted: Tue Jan 15, 2019 12:23 am
by cobbadog
Yep, I was aware of the pressure relief valve on the oil pump itself and as I mentioned "On the 30C engine it is on the filter housing". It was also the reason I asked "Are you getting pressure anywhere?" This would then direct you to either the pump or a bypass valve issue.
When I rebuilt my engine there was a gasket between the filter housing and engine block, so I made a new one and put one back. I am not saying that it was original but the gasket if fitted back to front would block one of the galleries.

Re: Oil prerssure

Posted: Tue Jan 15, 2019 5:38 am
by ollek
Talking about a 30C can be very confusing, when the tractor in question is a 885.

Re: Oil prerssure

Posted: Tue Jan 15, 2019 5:45 am
by cobbadog
No problems here ollek.

Re: Oil prerssure

Posted: Thu Jan 17, 2019 8:55 pm
by bedwards1966
I had an engine apart a couple of years ago and it wouldn't develop any oil pressure when cranking. The solution was simply that it needed priming by putting oil into the gallery/filter housing (at the pressure switch or blanking plug as I recall) using an oil can. It can happen when an engine is sat for a while in bits and all the oil drains away. Filling the oil pump with Vaseline is a trick which can help them prime.

I would not tow an engine that has no lubrication.