V8 Oil Pressure Light

[danny hoffman]

Driving to work this morning my oil light started to flicker at low revs once it was warm. The pressure gauge looks fine, 15lb at idle and rising as I rev - so I am hoping the switch is faulty.

Is it common for it to fail in this way?

Also can anyone confirm the part number, it's an '85 pre serp?

Cheers

Danny

[adam quantrill]

That is actually normal. It's working fine.

[danny hoffman]

It never used to come on at 15 PSI before!!

[ed_crouch]

it wouldnt be unthinkable for the pressure switch to click at 15lb. Theyre normally more like 10PSI...

Theyre not mega expensive, so Id change it to be sure.

Ive always found that the oil pressure in my cars has been slightly better after an oil change.

FWIW mine (58k mile 390SE, NCK engine) sits at about 25 - 30PSI on idle, rising to 50 - 55PSI.

However, dont be worried by that as I believe the 390 engine has a higher pressure pump. I think...

[adam quantrill]

danny hoffman said:

It never used to come on at 15 PSI before!!

Hmm - when you say low revs, if you mean below 800rpm on tickover, with the engine hot (90 or above), then the light flickering is not unknown.

Any rpm's above that, isn't normal. Certainly by 1000 it should be out.

I wouldn't trust the pressure gauge to be too accurate anyway, best to stick a known good gauge on there to calibrate both switch and gauge.

[wedg1e]

ed_crouch said:

However, dont be worried by that as I believe the 390 engine has a higher pressure pump. I think...

Not to the best of my knowledge. The one on my 390 is the standard SD1 variant. Though, of course, anything is possible with TVR...

[danny hoffman]

It was a faulty switch - phew!!

I had to fit an Intermotor one though as this was all my local motor factor had - lets hope it doesn't got the way of the rotor arm and dizzy cap of theirs I fitted recently

[350zwelgje]

danny hoffman said:

It was a faulty switch - phew!!

I had to fit an Intermotor one though as this was all my local motor factor had - lets hope it doesn't got the way of the rotor arm and dizzy cap of theirs I fitted recently

Is it a separate switch, or is it included in the oilpressure sensor for the gauge?
Had about everything of the wedge in my hands, but can still (and need to) learn.

Rob

[gsx600]

Theres 2 sensors, one for the low pressure light and one for the electric oil pressure guage. On mine I took another T off and fitted a hydraulic pressure guage fed by a capillery tube to get a true reading until I could fathom out why electric guage was useless