Low reading oil pressure gauge '87 TS

[teambee75]

Since purchasing car 8 weeks ago oil pressure gauge needle sits on minimum at idle and only moves up very slightly as engine revs increase. Not too concerned as warning lights function OK but wondering if anyone else has had similar problem? Is it likely to be in the sender unit or gauge itself?

[Pascs]

When the oil is warm/hot the oil pressure should be about 1bar at idle rising to about max 5bar from about 2500rpm onwards.

[j.k.QV]

I had a low reading sender unit on 164. As far as I remember after repairing the sender unit, it went bad after a week. So I wouldn't worry TOO much about the reading.
Still, it makes sense to check pressure at a garage, to make sure it's the sender and not the actual pressure.

[Mound Dawg]

Originally Posted by Pascs

When the oil is warm/hot the oil pressure should be about 1bar at idle rising to about max 5bar from about 2500rpm onwards.

Mine sits at 2 bar stinking hot at idle and 5 bar elsewhere. When it's cold it idles at 5 bar which tells you exactly why you shouldn't rev the engine hard with cold oil!

I agree it's likely to be a sender fault but you may also be using the wrong oil. Handbook says 10/40 or 15/40 but try Valvoline Racing VR1 20w/50 or Millers CSS 20w/50.

[eddiealfanut]

Hi,

Co-incidentally I had _exactly_ this problem just a couple of weeks ago. Same thing, low reading, but no warning lights, no smell of oil in the exhaust and nothing in the water. Had me worried but I got a new sender from Alfaholics and now have lovely pressure readings.

Simple enough job and cheap too, so worth it for the peace of mind I reckon.

HTH,

Ed.
AlfaSmiths

[Mike69]

I hope that this is just a faulty sender, but you really need to get the true pressure checked. Don't rely on the warning light, as they are designed to go off at tickover, with oil at full temperature. Therefore, your oil pressure could be dangerously low at higher engine revs, and the warning light would remain unlit.

[Unkle Munkle]

Mine doesn't work at all so wouldn't worry too much. They get gummed up and fail to work properly. You'll know if there's a serious oil pressure problem. Just give it an 'Italian tune up' - ie 7,000 rpm in as many gears as possible!

[teambee75]

Thanks for all responses. Sounds like Ed is on the money, will let you know how new sender goes when installed.

[porto]

hello there.in my ts i had the same problem with you and i thought that it was nothing but after 20k of hard work the engine faild.the problem was that i had lost one of the six crank oil way plug and i had low presure oil.YOU should chek this out if there is no problem with your instruments,but it is pain in the a.s because you have to remove your engine from the car.

The crank plug oilway dropping out is a VERY occasional problem on this engine, but not enough to make anybody worry about it.

99.9% its the sender, which is a well known failure item after about four years of use. The diaphragm inside it deteriorates and the readings just get steadily lower.

Having replaced three on different engines and restored the readings on all three its the quickest engine rebuild in history

Once replaced you should see a very healthy reading on start up from cold..up to 3 to4 bar. Once the engine gets hot the reading will fall and you may only get about 1 bar at idle. Don't worry about this, provided the OP needle responds well when you rev the engine then all is well.

AlfaLincs

[teambee75]

I installed a new sender unit last Monday but have been unable to report back due to forum renovations. Very happy to say cold idle pressure just under 6 bar & warm idle around 4 bar which makes me feel more confident about supersprinting this Sunday. Cheers to all contributors.