10 replies to this topic

[tino]

Ive searched the forums and found nothing similar.

When I start the car up I get no oil pressure reading on the gauge unless I go about 100 yards down the road when it returns to normal. This is when hot or cold.

If the car is left to idle and no moving then it remains reading nothing. Ive left it idling for 10mins+, but if (after ive got a reading) I dont stop the engine its fine when at lights etc.

When I pull away and rev the engine a little you can hear a crunching/grinding noise from the engine until the pressure is reached but I dont get this noise unless im moving forward if I rev while staying still I get normal noise and still no reading.

I think it started to occur after I took the rocker cover off to adjust the tappets, I did't glue the seal back on (its a new seal) would this cause the drop in pressure at the start?

When its reading again after the first 100 yards everything is fine and as usual there is no difference from when I normally drive her. So any idea's what it could be? I ive change the oil as it was pretty old before. Got a new gauge so I'll try that next just wondered if any of you have experinenced this before? Or know what the problem is.

I think that explains it well enough. Im not loosing alot of oil by the way and its a new head gasket with normal compressions and no blue smoke.

[Dan]

Electric or mechanical oil gauge?

[tino]

mechanical, 1979 mini 998. If you need that aswell.

Oh and the low oil pressure light doesnt come on, although im not sure if ive got one anyway....

[Big_Adam]

Mine does that too. Take a moument to get the pressure up. Don't know about the other stuff tho.

[paulrockliffe]

Is it really the first 100 yards, or after a certain amount of time? If you're not sure, time it and see.

Mine does exactly the same thing, it's because it takes some time for pressure to pick up.

Does anyone know if having air in the connection pipe to the gauge affects the reading?

[Stoo]

Sounds like the pump's not priming properly at startup. Mine takes a few seconds to prime but I gently blip the accelerator to get pressure ASAP so the engine doesn't run dry for too long. DONT let it idle with no pressure!!!!!

My first thoughts are you've got a worn pump -

Having air in the guage pipe won't affect things.
What is hot idle pressure (once it's primed)? - This will tell us a bit more.

Stoo

[tino]

Once its been on a long run and idle's it sits at 1 kg/cm^2 (what the manual ive got says is correct) at load its between 3 and 4.5 depending on how long a drive ive been on. (also within the range given)

Its always from my house to the end of the road (crossroads) so 100yards or less but in that time.

The oil pump has done about 90,000 miles now so probably is getting a little old.

Thanks for the help.

[tino]

Hmm it was even longer today and the engine did't sound at all nice while I was driving it so I think ive gota sort this soon. Is there anyone in the Southampton area that could help with a engine out job as ive not really got the space to be able to work on the engine (uni accomodation) or should I just pay the £400 that the garage said they would charge me for a part that cost's £30 + lots of labour....

Thanks for the help

[*DJH*]

I had that... then the engine seized up.

[tino]

Thanks...

New engine then...sigh one problem after another

[minidaves]

370quid to fit an oil pump not bad for 4-5 hours work.

dave