Low Oil pressure.

[billwill]

Alas I haven't used my S3 since last August and when I tried the engine last week, at first it didn't create any oil pressure, then it was OK for a few minutes & then went down to zero pressure, so I somewhat hastily turned it off.

I suspect the most likely candidate for the problem is the relief valve stuck open by some gunge, so when I've got some flushing oil (and some proper oil) delivered I intend to take the oil pump off & give it a thorough clean, then use the flushing oil and if all goes well the proper oil later.

Does this sound like the best approach?

Bit of a b**g*r really as I'll have to lift the front of the car inside my narrow garage, without engine power to drive onto some ramps, so that I can get underneath to access the pump and the drain plug. And due to the virus lockdown, I can't ask anyone to help either. I don't have a car lift.

Hey ho.

[ericbushby]

Hi Bill,
It might just be worth replacing the oil filter.
I believe that I had one collapse internally once. It was about 50 miles after an oil and filter change when the pressure reduced gradually over about two miles.
I recovered the car to home and did a lot of work investigating, but it was after I changed the filter agaln that pressure was restored.
It was quite a while before I watched the speedo more than the oil pressure.
Best of luck
Eric in Burnley
1967 S3SE DHC

[2cams70]

Dumb ass question but did you check the oil level? Also you can easily access the pressure relief valve after removing the filter. Check that it's correctly seated and see if it moves freely by gently levering it upward with a screwdriver. You don't have to remove the pump from the engine to do this

[ericbushby]

Bill,
Just another quick thought.
I believe you have a modern starter motor fitted. If you take the plugs out the starter should take it up the ramps. Maybe!!
Let us know how you get on.
Eric

[512BB]

Now that is a bummer Bill. As you no doubt realise, its a lot of work to remove an oil pump in situ. Engine has to be moved over to get it out and all the work that involves.

Had low oil pressure on an engine I built a couple of years ago. It could not possibly have been the workmanship, as that was faultless So it was either the new oil pump or a faulty gauge, which was original. My guess was the new oil pump, but before removing that, I plumbed in a spare gauge, same result, low lbs. Replaced with the original from new oil pump, lbs restored.

I will send you my spare gauge Bill if you want to try it. No deposit required I have a few new oil filters laying around, if you want to fit one of them at the same time, £s required.

Moral of the story. If you rebuild an engine and you know that the old oil pump was sound, refit it. New no name oil pump quality is utter crap.

Leslie

[billwill]

I did check the oil level, it was down a bit, but not serious; about half way between the FULL and FILL marks. What was most worrying was that by looking through the oil filler cap the cam chamber looked rather dry.

I haven't any spare unused oil, so I'm going to order some.

I hadn't realised that there isn't enough clearance to get the oil pump out without moving the engine, that's a b****r.

My starter is a standard Lucas type, but I could try spinning it with no plugs after I've had a bi of a fiddle with the relief valve.

There's a LONG Lotus type oil filer on at present, but I have a short spare one, which I was going to use with flushing oil, so I can try swapping to this new one. I don't think the problem is the gauge itself, because it worked for part of the checking & then went down to zero bobbing about a bit. It's relatively new the gauge was changed around 2001 It's a capillary type of course being an S3 Coupe.

[englishmaninwales]

From memory, I think with the oil filter off you can see the piston for the relief valve - then determine if it’s stuck open.

[h20hamelan]

From memory, I think with the oil filter off you can see the piston for the relief valve - then determine if it’s stuck open.

Do you have an inspection camera, or a good light to shine up using an old mirror

[billwill]

Luckily I have one of those tiny round cameras that you plug into a laptop for inspecting nooks & crannies etc such as through the plug hole into the firing chamber.

[benymazz]

Throwing ideas out there - if it's not the relief valve it's possible that the pickup tube has come unthreaded. I can't speak for how the pickup works for the 6 bolt engines as I believe it's different than the 4 bolts but on my 4 bolt engines at least the pickup pipe (the one with the strainer attached to the end) screws into the block and has a locktab washer that's intended to prevent it from loosening.

-Ben

[billwill]

Mine is a 4 bolt engine bottom part. Not sure why as I think it's manufacturing date was well after the switch to 6 bolt, however I haven't double checked that date.

I haven't modified the cross support to be removable, so I hope it isn't your diagnosis as it will involve engine out or do that mod, to get the sump pan off.

[RichardHawkins]

Bill,

My car is a 1968 S4 FHC. This car has a 6 bolt crank, the oil pick up pipe is a force fit into the block.

Hope this helps,

Richard Hawkins

[englishmaninwales]

My S3 had a ‘cross over’ block with a 4 bolt crank and a push in pick up. The push in type it cannot come out as the sump will prevent it.
Is the oil pump a modern replacement? My Burton supplied replacement the release valve piston was tight and needed fettling to ensure it wouldn’t stick open.

[alan.barker]

I have removed an Oil Pump with Engine in Car. You just need to remove the 2 Screws that go through the Engine Mounting and Chassis Lug. With a spreader under the Sump use a Jack to adjust height of Engine on Oil Pump side so the Oil Pump clears the Chassis Flange.
Alan

[pharriso]

I have removed an Oil Pump with Engine in Car. Yuo just need to remove the 2 Screws that go through the Engine Mounting and Chassis Lug. With a spreader under the Sump use a Jack to adjust height of Engine on Oil Pump side so the Oil Pump clears the Chassis Flange.
Alan

Agreed, just changed my pump this way, took an hour start to finish, mind you carbs were off...