Oil Filter Seal Blowing
Turbo Mini Forums

Well this stinks!
I started up the car thanks to the help from my other thread and pretty much immediately the oil filter o-ring/gasket popped out shooting oil out into the fan and across my garage.


Talking with a friend we assumed with was a pinched oil filter gasket so we threw another filter/gasket on with plenty of oil to lube it up. Tried again and BOOM! There it goes!


I checked my oil pressure gauge it was actually broken and stuck in the max position-probably not good, eh?


I pulled out my oil pressure relief valve and it looks to be the correct spring and the valve slides easily in the shaft. It doesnt seem to be stuck but maybe under high pressure it could be?
I also measured the approximated fitted depth of the plunger and it matches to Haynes.


I'm not sure what else to look at here, maybe it's a clogged feed line somewhere?
Or could it be the turbo oil pump on the 998 block?
Should I swap for the ball bearing instead of slider?
Cut some lengths of the spring?

I'm worried about damage the oil seals on my turbo.

As always, I really appreciate your help.

Edited by seahuston on 20th Apr, 2016.

Have you plugged and redrilled any of the holes on the underside of the block while having it apart? Possibly plugged the oil return hole? A so called professional engine guy here in Norway did that once, and it caused exactly this behaviour.

Here's a shot of my block before I assembled it, looks like the drain hole is clear:


I did use some gasket sealer while mating the engine to gearbox. I wonder if that could have plugged the holes? It's a pretty big hole to plug though. I can think of any way to check this without taking the engine out/apart.

For the fun of the thread, here is a pic I found of the galleys:


Looking at that pic, I'm wondering if that plug I used to seal the small hole in the circled area is too long and causing hydraulic lock by blocking the intersecting pipe as well.

Edited by seahuston on 20th Apr, 2016.

Update!

I really hate my past self!
The plug I put in that cross way was too long and was definitely blocking the vertical way. This would cause hydraulic lock and result in the valve not being able to open.

Jeez I feel like I fool but hopefully that solves it. Should be a pretty quick fix.

This is all character forming and helping you to bond with your car.

Good learning :).

Not sure if you've got a ball bearing on the end of your spring or just a plunger? I run a plunger, with three holes drilled around the outside where it slides in the bore. Reduces the chance of it getting stuck.

Glad you found it, I have had a similar problem before with excess oil pressure, it seems the filter seal is the weakest point.

I have a block in my garage which does exactly the same thing. It turned out to be a factory brass plug fitted in an oilway just behind the relief valve preventing it working. Think the block came from an inline engine

that is a jolly interesting section, I never realized the main beaing gallery and oil relief valve intersected,

IIRC there is somthing in the Vzard book about some blocks not having the relief vaolve seat fitted... and hence no oil pressure.

mind you that appears to be a a small bore block judging by the start of a tapet chest and 1 core plug.

In the oilway circled mine has a brass plug fitted

On 20th Apr, 2016 Joe C said:
that is a jolly interesting section, I never realized the main beaing gallery and oil relief valve intersected,

IIRC there is somthing in the Vzard book about some blocks not having the relief vaolve seat fitted... and hence no oil pressure.

Here is the block diagramed as I understand it.


Red line is the pressure relief oil pathway
Green line is the pathway which just acts to prevent the valve from hydraulic lock. There shouldn't be a lot of flow through here.
Yellow is where the plugs should be installed.
Blue is the ball.

When my engine was machined, the brass plug in the cross way was drilled out so I, feeling like a smarty, put a bolt in to plug like Vizard suggests for the other plugs. Bolt was quite long and likely full blocked the flow path.

So now I'm going to knock up a new plug on the lathe tonight. Any suggestions on how to make it? They are solid plugs stock but I'm wondering if I should put any taper on it? I was thinking just a slight interference (.002" or so) and guide chamfer on the end. But then also thought that maybe a couple degrees of taper on the length could help installation and holding.

Make it parallel, it then is a fit along its whole length which will be sufficient to retain it. Make it tapered and it will only be a fit in one spot around the plug.

Solved! Knocked up a plug for it today.

Ended up being 0.255" diameter and about 0.35" in length. I installed with with red locktite to help hold it in.

The stock plug doesnt have the flange on the end but I left it there and didn't press the plug all the way in. This way I can lever against it in case I ever need to get it out.