Oil pressure problem

Oil pressure problem

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netley

Original Poster:

5 posts

154 months

Saturday 13th September 2014
quotequote all
I have a '94 3.2 Jaguar X300. My problem is the car starts and after a minute or so the tappets become noisy. Then I noticed no oil pressure on the gauge though there is plenty of oil showing on the dipstick. I haven't run it since as I'm afraid of serious damage.
I'm stumped as to where to start. I'll try to get a pressure gauge to test off the block but that will mean starting it and I think that could be a bad idea.
It had been stood for quite a while but I'd run it a few times to move it around to address other problems.
Any ideas where I should start looking?
Cheers
Neil UK

Jaguar steve

9,232 posts

210 months

Saturday 13th September 2014
quotequote all
No oil pressure at all would suggest an indication fault. Does the oil pressure warning light go out? If it does then you do have oil pressure just no indication on the gauge. IIRC in response to customer concerns Jaguar changed how the gauge was driven sometime during the X300 production run from a actual pressure sensor on the block to a electrical simulation representation of oil pressure. You will need to research this to help diagnosis.

Fitting a master mechanical gauge will prove for sure or not if you have oil pressure. In the meantime I'd suggest you fit a new filter to rule blockage out, carefully re check oil level and then start up again. You could always fit a new or known good oil pressure switch wired into a separate stand alone circuit to see what happens when you do to rule out any continuity problems.

The oil pump is driven by a single short chain at the front of the crank. If that's broken or the pump had failed you're into some serious engine work. As far as the engine noise goes then that could be an indication of either top end oil starvation or just ticking injectors but the AJ16 has quite noisy valve gear even when healthy so it may be you've just noticed that whilst looking.


netley

Original Poster:

5 posts

154 months

Saturday 13th September 2014
quotequote all
I'll get a pressure gauge on first and take it from there.
Cheers
Neil