Oil light fun

[Scar]

Got my Stag back from the mechanics a few weeks ago after some fairly extensive and expensive mechanical and electrical work. Got about 2 miles up the road when the oil light came on, so I drove it straight back! They checked the level and it was fine, and blamed the sender. Figured its MOT was due in a couple of months anyway so I'd just get it done when I brought it in for that.

After driving it for a bit though, I've noticed when the engine is cold, the light is only on at idle and disappears when the engine is revved. Once the oil has reached running temperature, the light stays on all the time. This to me doesn't seem like a dodgy sender. I'm planning on taking it back again but not sure they've done anything that could have upset the oil system - they replaced water pump and cam cover gaskets but that's about it, so no need to go draining oil I'm assuming.

How worried should I be about this? I don't plan on driving it again until I've sorted it, but I've already covered 50 or so miles (no worrying noises). Have read it could be anything from clogged filter to dodgy sender to knackered bottom end! Unfortunately I don't have an oil pressure gauge fitted.

[KOY 23]

I would be worried and I would not drive it until I knew there was good oil presssure. You need a pressure gauge connected to get a meaningful diagnosis.

[len]

i would start by getting an oil pressure gauge , it doesnt sound good, most likely bearings gone.
Len

[Scar]

I've bought a new oil filter so will get that fitted and an oil change carried out in the hope that maybe that's the problem, then I guess I'll get the pressure checked afterwards to check.

[StagJonno]

Likewise, I'd be worried too. Worth getting a new sensor if you don't want to go the whole hog of fitting an oil pressre gauge. Might be worth trying a new sender (http://www.ldpart.co.uk/shop/shop.ph...169cec0f5e9efe) to rule that out. Unless you've got a dodgy filter (which is causing a blockage), just changing the oil is unlikely to make the sort of difference you're looking for. IIRC, the oil pressure switches operate if the pressure goes below ~6psi, whereas an engine in reasonably good nick will have a hot running pressure of ~40psi @ 2,000rpm.

If you're not hearing any bottom end knocking or rumbling, it could be that your main and big end bearings are still OK. The next place I'd be looking would be the oil pump (cheaper than a speculative engine strip down).

A proper oil pressure gauge would help you get a better idea of what's going on - you can get a combined oil pressure/ water temp gauge (including a T adaptor for the oil and an adaptor for the water capiliary bulb) for ~£100 plus fitting and replace the existing Temp gauge. If going this route, I'd recommend that you get one with theperature scaled in degrees C rather than "C-N-H"

Jonno

[Scar]

The clock doesn't work so I was considering getting an oil pressure gauge put in there... Wish I had now!
Just seems odd that before it came on literally on the drive away from the garage I'd had no problems. Would have expected to see it first come on at hot idle if it was something more progressive like the bearings going? The fact that it suddenly came on and stayed on suggests to me more like something has just happened rather than a slow decline finally tipping below the 5-6psi to trigger the light. Engine sounds fine and again I'd expect the garage would have picked up on any problems considering the number of road tests they took it on. Plus at less than 5 psi I would have thought the engine would have seized within the 50 or so miles I've done on it since... Or maybe I'm just clutching at straws that I don't need a full strip down and rebuild!

Steve

[Goldstar]

Is the sender connected? Not even sure that would show your symptoms without reading up but it’s bedtime so
ill throw it out there as you don’t mention checking it.

[I am Groot]

From what your saying all sounds fine. Possibly oil pump and/or very tired pressure relief spring. Get an oil pressure gauge and then if pressure is a bit low but crank sounds ok try a new pump if you have no record of it being changed. Bed time!

[davidf]

Most likely a problem with the sender or circuits; next most likely is the oil pump relief valve. Easy to rig up a pressure gauge; that is an absolute measure of what you have.
See also a recent post about oil pressure problems - someone had assembled the filter incorrectly after letting all the bits fall off the central bolt (retaining clip was missing). If your problem has just happened after a service, that is also a possibility.

https://socforum.com/forum/forum/stag-owners-club/soc-forum/758794-oil-pressure

[Kithmo]

Is the sender connected? Not even sure that would show your symptoms without reading up but it’s bedtime so
ill throw it out there as you don’t mention checking it.

I was thinking the same, or the wire could be chafing somewhere and earthing out.

[Scar]

I was thinking the same, or the wire could be chafing somewhere and earthing out.

Sender is connected - first thing they checked when I took it back after driving it off. They disconnected it and the light went out - they did ask whether to just leave it off but I thought that was probably not the best idea! Taking it back this Thursday for them to check the pressure properly. Have got a new filter from LD parts on the way and will ask for an oil change as well - hasn't been done in the 6 months I've owned the car and whilst it has still only done 200 miles since it was put back on the road and MOTed after a 10 year lay up it's probably a good idea.

[Hughesy]

It sounds too much of a coincidence that the car was fine and then after "some fairly extensive and expensive mechanical and electrical work" you immediately have a problem. What work did they do? Are you sure it is not related to their work? Craig

[Scar]

It sounds too much of a coincidence that the car was fine and then after "some fairly extensive and expensive mechanical and electrical work" you immediately have a problem. What work did they do? Are you sure it is not related to their work? Craig

Water pump replaced, so carbs & inlet manifold off. Both cam cover gaskets replaced as one was leaking oil. Choke cable replaced. Overdrive solenoid replaced.
Electrical - voltage regulator and rheostat for dash lights replaced. High beam indicator switched (previously on when using dipped beams, off when high beams on), interior lights fixed, radio & speakers fitted. They wouldn't have had a need to go near the bottom end so can't think of anything that they might have done, but yes does seem odd timing.

[steve.n]

Scar, was the work done by a Stag specialist?
In the interests of customer relations I would expect them to be interested in solving this, maybe checking the oil pressure, I would not be driving without knowing what oil the pressure is (Engine pressure not pump pressure)

[Scar]

Scar, was the work done by a Stag specialist?
In the interests of customer relations I would expect them to be interested in solving this, maybe checking the oil pressure, I would not be driving without knowing what oil the pressure is (Engine pressure not pump pressure)

Not a Stag specialist in particular though they have worked on them, but classic specialists with complete rebuild services. Usually a good mix of e-types etc there so they're certainly trusted.

Just had a thought - water pump has an oil seal etc. Is there any way this could have failed/not been fitted correctly? Should I be looking for oil in the coolant?