Oil pump priming difficulty

[RichardF]

I have just installed a temporary replacement engine. It starts and runs lovely but the oil light will not go out.
I know it's lack of primimg even though I have followed the manual and pressed plenty of petroleum jelly into the pump gears. When I remove the filter, it is not full as usual and I can see some of the jelly protruding from the base of the pump, so it seems to be pushing it a bit. Also no oil drips from the spout that feeds the filter.
I have removed the sump and checked the oil pick-up and strainer; they are clean and tight. Also plenty of clean oil and I fill the filter prior to fitting.
Any ideas folks?

Richard
Southampton

[harvey]

Did the engine come complete with its distributor or have you fitted your old distributor and fitted it to an SD1 engine so it's now an Sd1 engine fitted with a P5B distributor?Or has the old style front cover been fitted with a hi volume kit using SDI gears. Other causes can be a damaged front cover gasket. Have you put a master gauge on it to confirm you have no pressure.
I know it's a difficult thing to do with the oil light staring you in the face but sometimes they won't build up pressure on tickover alone you have to give them a LITTLE rev up. (Obviously not too much as you've got no oil pressure, nice "Catch 22" eh!)

[RichardF]

Thanks for the prompt response Harvey. I have swapped the distributor as my original one is electronic. I'm pretty sure it and the pump spindle connect okay as moving the spindle of the pump with the filter housing off gives me the feeling of a small backlash, inferring that they have mated okay.
Starting is with the choke and is pretty fast idle anyway; so much that I had to slow it down a bit by pushing the choke back in a bit.
The pump is the high volume type as is my original engine. I'm wondering if it would be okay to remove the dizzy and use an electric drill with suitable attachment and try to prime the pump that way. I could also see if the oil warning light goes out aswell.
Richard
Southampton

[harvey]

You can use a drill to prime it up, several companies sell a drive to fit in a drill for this purpose. Just make sure you have the drill running the correct way. Can't say I've ever had to do it this way though.

[RichardF]

Thanks Harvey.
Afetr a few more basic checks, I'll give it a shot with a drill and attachment. Thanks for the heads-up about going the right way.
Richard
Southampton

[Phil Nottingham]

I have heard of this trick but it should not be necessary normally - it could point to a worn pump or even worn bearings although even worn rocker shafts can cause low oil pressure. Even if it does work, it may loose its prime after standing or oil change.

The oil light sender is certainly suspect on a unused engine as te rubber diaprhram in it quickly hardens although it certainly does point to loss of prime - I always fill an new oil filter completely after an oil change as I know of cases where the prime goes after an oil change but otherwise engine seems fine - although I have not had this personally

[Smallfry]

Vaseline should be ejected quite forcibly and obviously. If its only showing a little, it points to the pump drive. Even with an air leak (oil pick up pipe or front cover gasket) it will eject the vaseline.
Check the obvious one first, pump shaft to distributor compatibility. One will have a tongue and the other a slot.......this was reversed on later engines, or the not so obvious one of the drive pin through the distributor shaft sheared, or even the pump gear slipping on its shaft.

[harvey]

If the drive pin shears it will be the distributor that loses drive not the oil pump. The oil pump gear spinning on the shaft is a possibility, but I've never come across it happening.
If you remove the pump cover to pack the pump with vaseline again, I would take the opportunity to strip out and check the pressure relief valve.

[Welsh Warlock]

Friend had similair problems on a Chimaera engine and spent many hours checking and rechecking seals and in the end handed it over to a garage who couldn't find the problem.

A second garage found the oil pick up pipe alomost completely blocked with sludge. Mostly happens where an engine has stood for a while apparently.

[RichardF]

Thanks folks for all the inputs. Problem was solved. I carried out all the very basic checks such as dizzy shaft to pump spindle compatibility, changing oil pressure light switch for known good one, rammed some more vasilene into the crevices of the pump and double checked the oil sump level (after cleaning the pick-up pipe and strainer). Still would not prime after all this. I cured it by removing the dizzy again and making an adaptor to drive the pump via an electric drill (clockwise). Even this would not work at first but after a second go, the oil light went out. I fitted the dizzy and the car started with the oil light going out straight away. After getting the engine hot, I switched off and left for 30 mins to see if the problem would return or the oil light taking ages to go off. However, all is well; the light goes out the instant the engine fires. Thanks again for all your help guys.

Richard
Southampton

[Deleted]

Good result, well done Richard, reflief all round then?

Freddy