admiral

Can anyone tell me please the trigger pressure of the oil pressure switch on a YB in a 1988 Sapphire Cossie?

costina

iTrader: (1)

Think its around 15 psi.
but change the switch first as they do fail.
Best to get a good quality gauge in there too be sure.

On a used engine your looking at around 60psi cold and 30 psi at idle when up to temp using 15/50 good quality oil. Dont use anything made by comma.

admiral

Many thanks Costina for speedy and helpful response. Have just fitted gauge and discovered lowish oil presure (3.4 bar cold, 2 bar hot with 0-60 oil). Car has been in storage since 1990 (30k on clock) and has been flushed but I suspect strainer is still blocked. I have a new oil pump handy in case.

martysmartie

iTrader: (1)

Nothing wrong with that, it's exactly what Costina said, in the latter case.

Personally I wouldn't use that viscosity though, I use 15/50.

Martin

costina

iTrader: (1)

I used to use mobil 1 15/50 which was ideal for a cossie. I now use Fuchs titan 10/50.

I wouldnt use any additives that so call clean it can cause more issues than its worth. Just do a couple of oil changes 100 miles apart with a quality oil.

admiral

Sorry should have made it clear my pressure readings were at 2000 rpm and above, not at idle so not so good. I only used 10/60 to prove a point and will probably run on a 10/50 in future - when I find the problem!

costina

iTrader: (1)

Hmm 30k is nothing mine has 93k and still has good pressure.

What type of gauge u using? mechanical or electric?

admiral

Electric - but have also checked pressure mechanically at turbo as in workshop manual. Sadly it showed electric reading was spot on.

costina

iTrader: (1)

what is it at idle? is the light flickering? Hot

admiral

Just under one bar. Hence my initial query about the oil pressure switch - light is not coming on. W/S manual says hot idle should be minimum 1.8 bar. There are no unseemly, expensive noises from the engine indeed it sounds as sweet as the Andy Rouse 304 I had 20 years ago - wish I'd kept it!

costina

iTrader: (1)

Time for the sump to come off if the strainer is gummed up that can cause issues.

What about your turbo? if it had excessive clearance on the bearing it could be enough to drop pressure???

Just a thought you could blank off turbo feed and check pressure. Quick check tho.

admiral

Yes, sump coming off next week. I'm new on this forum - how do I give you a "thanks" ?not that you need any more!!!

costina

iTrader: (1)

I have no idea. But hope you find problem and it is not expensive.
get yourself some of that fuchs oil from oilman on here and use a genuine motorcraft filter.

Regards

Paul