Evening all. Just refitting an oil pump. Should there be a gasket between the pump 'plate' and the casing it is bolted to? I dont think one was there when I dismantled it but it was a long time ago...
Presumably a good seal between these component would be a good idea to maximise the pump performance.

There is no gasket between the pump body and the timing-chain cover. Just make sure that the surfaces are absolutely clean and the 4 screws are done up tight. Before you fix the pump to the timing-chain cover, pack it with petroleum jelly (NOT grease)--this will give the pump something to suck on upon initial cranking and will bring the oil pressure up quicker. If youare fitting a new oil-pump you MUST fit like-for-like, you must NOT mix 500 and 126 parts, the pumps are slightly different--500 pump with 500 timing-chain cover; 126 pump with 126 timing chain cover.

Thanks for the advice. In this case I am refitting, but good to know!

Hi,
Can one access the oil pump with out removing the engine? I took the engine out to replace the pistons but neglected to check the oil pump. I now find I have zero oil pressure... rookie error doh!... which may have been the primary problem all along! Thanks.

Without looking back through all your listings did you just fit a 540cc kit to a engine with low oil pressure? Zero oil pressure would have to be down to an extremely worn or broken oil pump. More likely to be down to core plug loose on crank, worn bearings and crank, faulty oil pressure switch or oil has just not found its way around the engine yet.

Yes Toshi, I’ve replaced most of the top engine but did not check the crank shaft or oil pump. That seemed a lot more challenging at the time. I had forgotten to replace the oil pick up seal but no better with it. Measured by using a proper guage at the pressure switch. I suspect the answer is to take the engine out and apart again armed with better knowledge!

Before you rush into anything have you ever removed the sump to look in there?

Sensible suggestion by Dave (Toshi) to rmove the sump and check things inside 1st (drain sump before you remove it!). Check that neither of the crankshaft core plugs have come out and that there is not excessive vertical play in the con-rod bearings.
The oil-pump CAN be removed without taking the engine out, as long as you can work out how to 'lock' the flywheel in order that you can undo the big crankshaft nut (149 Nm tightening torque--it is tight). If you do get to renew the oil-pump you MUST renew like for like--don't be tempted to fit an 'uprated' 126 pump if the original pump is a 500 unit.
If you are going to renew the oil-pump with the engine 'in-situ', I would suggest that you check the crank first, then re-fit the sump (even if you only fit 50% of the retaining screws) before you try to remove the rear cross-member.
Having the sump in place will give you the ability to support the engine with the cross-member not in place.