K100 8v Morris Marina Conversion
Turbo Mini Forums

Brilliant! Have you sorted the handling to stop it reversing into the nearest hedge?

'Where does the engine go?'

Beware of falling pianos

Engine now run in. At the rolling road yesterday. Mapping going really well until at at about 3500 revs sudden reduction in oil pressure as revs rose further.

Has anyone experienced this, what was the cause?

Engine now run in. At the rolling road yesterday. Mapping going really well until at at about 3500 revs sudden reduction in oil pressure as revs rose further.

Has anyone experienced this, what was the cause?

Engine now run in and at rolling road yesterday. Mapping going well, until sudden loss of oil pressure as the revs rose.

Has anyone had this problem on an A series based engine, we were stumped. Researching on the net at the moment, ahead of the inevitable strip down.

first thing I would check is the oil pump gasket,

there was a known issue with not enough face area between the pump and the cam bearing to grip the gasket properly, minispare revised their pumps, but it seems it may still not be enough. their Evo pump should have plenty of area, but its as well to check properly.

failing that theres not a lot else that could caus this wothout you seeing a biig pool of oil, maybe the releif valve stuck open, but that would normally show at idle and pick up abit through the revs

Is the sump oil level correct? I mean have you got the correct dipstick in there, low oil level could lead to loss of pressure as more oil is up in the engine as the revs rise.

'Where does the engine go?'

Update: car now on the road and MOT’d. Run in for 500 miles at under 3000 revs and off to the rolling road to finesse the timing and mixture and then do some power runs.

Had to abandon the power runs, when the oil brewed up at 3,000 revs and the oil pressure died away to nothing. Part of the problem was that the oil pressure relief valve had popped and stuck partially open. Now replaced with a ball beRing and new spring.

Unfortunately, it hasn’t cured the major loss of oil pressure at around 3000 revs.

Has anyone experienced this problem? What did it turn out to be and what was the eventual fix?

Sorry about the duplications, could see the various versions, mods can you delete as appropriate please?

The position of the throttle bodies means that I can’t use the standard dip stick, so I fitted the Specialist Components curved dip stick tube and bendy dip stick.

It is possible that I may have overfilled the sump, so that there was a windage problem (crankshaft whipping up the oil). The Marina engine should have 3.7 litres oil in total including the oil filter, so now I am measuring it in from a measuring jug and remarking the dipstick, if only to eliminate that possibility.

I am interested in the comments about the oil pump tolerances. Is it only the MiniSpares pumps. I am wondering whether a genuine OE MG Turbo would be OK? Cheapskate really 😁.

Edited by Carboy0 on 8th Aug, 2019.

Is the gearbox in sump oil level different to a conventional sump level, and the specialist component dipstick is specified for the gearbox in sump A series?

Errr - not sure, good call. Guessing that they will be different, hence my comment on re-marking the dipstick.

I am surprised that the oil contents including filter are as little as 3.7 litres.
I would think it is at least 4.5 litres.

Yes so did I, but as per the BL Repair Operations Manual.

Looking to buy the MiniSpares Evo pump at the moment, only to find that they are out of stock and can’t give a delivery date.

Edited by Carboy0 on 12th Aug, 2019.

So, given the above the Metro Turbo option is next best thing. I noted that it’s only a two bolt fixing unlike the Evo pump four bolt fixing. Has anyone had any experience of drilling out the two corresponding extra holes and fitting the extra bolts?

I can’t see why it would be a problem, unless anyone has done it before and come unstuck?

Pretty sure I have on mine with no trouble.

Great stuff thanks

Update - engine out, Metro Turbo oil pump in. Start her up loads of oil pressure at tickover 80psi. Rev her up and at 3000 revs the pressure starts to drop off again down to 25psi and falling. I was so pl**ed off that I though ‘sod it’ I may as well break the engine and gunned it.

Suddenly the oil pressure jumped up to 70+ psi and there’s been no reoccurrence. I’m guessing that there was some lose sealer stuck in an oil gallery from the first rebuild and the extra flow of the Metro Turbo pump has washed it through to the sump.

Now waiting on getting back to the rolling road for some power run figures. I have chickened out on the road in low gears at 5000rpm and she’s still pulling like strain.

Could it be a sticky relief valve? Easy to pop it out and check. Used to be the accepted mod to remove the standard spool and replace it with a ball bearing which cannot stick.

This has appeared in PPC mag this month, good read, tidy conversion.

Shane