Slow Oil Pressure
Turbo Mini Forums

Having just done a gearbox rebuild and dropped the engine back in, I've hit an oil pressure problem.
Every time I start up it takes 10-15 seconds to build up oil pressure, once it starts to build it ramps up quickly, just takes a while to initially move. Gauge and light register at the same time, so its not the gauge gone duff. Once pressure's there, it stays there - no fluctations or anything.

It used to be pretty instantaneous. The only thing 'engine' side I changed during the rebuild was the oil pump itself and I fitted the turbo one from Minispares as I was advised the greater flow would be good as I run a cooler. Previously I'd used a standard pump - are the turbo ones prone to 'draining down'?

Edited by graemec on 1st Sep, 2014.

O ring?

I run a supercharger and I don't care the TB is on the wrong side.
VEMS + 12 PSI + Liquid Intercooler = Small Bore FUN!

what oil?

ive not had any drama with my "turbo" pump in the new build

did you check the clearances before fitting it?

maby the oil filter is letting it drain back? ive noticed different brands have varying standards of quality when cutting them open some have purely made drain back valves that wont Evan stop a breath blown into it..

not sure if you guys can get the ryco brand but thats what i use number Z68

I think Graham is referring to O-ring between block and box..

Dazed and Confused....

This sounds like a badly machined pump if you are sure an o ring was fitted... Did you open and inspect the pump? I always do this just to make sure all is well and there is no swarf or stray casting flash ready to break off hanging around in there. A quick feeler gauge check will verify the pump clearances.

O ring was fitted, unless it fell out when I dropped the box onto the block (if it did, it fell inside not out!). I think without the O ring I'd struggle to get any reasonable pressure at all wouldn't I?

I did take the backplate off the pump to check for swarf etc, but must admit I didn't measure it up.

Edited by graemec on 1st Sep, 2014.

I always gasket seal the o ring into place, that way I'm 100% sure it's not going to be a problem for me.

Schrödinger's cat - so which one am I ???

Sounds like either way it's a pull it apart and check

I run a supercharger and I don't care the TB is on the wrong side.
VEMS + 12 PSI + Liquid Intercooler = Small Bore FUN!

Hmm, genuine gasket and the o ring was new and held in place with grease as I always do - I doubt it isn't in there.

Looks like its a least end cover casing off though. Arse.

It's not the oil pickup pipe gasket or something is it? Don't think that's been mentioned yet.

usually what happens here is where the O ring sits on the gearbox the gasket covers the O ring and never seals correct, causing this classic problem i have found out

what you need to do is cut around the gasket to expose the O ring so it can seal correctley between the gearbox and engine block,

also i have one turbo oil pump from minispares which was goosed in the past

+1 one with benross

i had to trim the gasket so it cleared the rubber o ring i was not happy to let them over lap

+2 trimmed the gasket when building my small bore

I run a supercharger and I don't care the TB is on the wrong side.
VEMS + 12 PSI + Liquid Intercooler = Small Bore FUN!

Missed that trick.
An expensive lesson by the time I've spent the time and wasted all the gasket!

the OEM gasket were trimmed the copys are NOT this is one to watch for gents as it gave me a large pain in the rear

’77 Clubman build thread
http://www.turbominis.co.uk/forums/index.php?p=vt&tid=618189

Siamese 5 port EFI testing
http://www.turbominis.co.uk/forums/index.php?p=vt&tid=611675

graham, i would replace the OEM relief valve set up. as a start.

your problem will most likley lie with the gasket problem as mentiond above.
new oil pump problems are very rare.

if you have a oil cooler fitted and the hose sticks up in the air that could be your problem also ? keep us posted

Well, I've found black rubbery bits on the dipstick, either rubber or RTV, but feels strong enough to be rubber - guess the O ring did dislodge on assembly.....
Out again next time I'm off work then!

Clean the area with thinners and super glue the seal in, also don't forget about the gasket mod above. Keep us posted

How much do you cut away? Just the OD of the O-ring or a bit more to make sure it's clear?

just cut say around 1mm all the way around the seal on the OD enough to expose the seal so it does its job ok and a little clearence