I've built my first engine!

[Cooper1999]

Through necessity - it cracked a piston.
After carefully stripping and reassembling, it started first time .
The ecstasy quickly turned to agony when I realised the oil pressure light wasn't going out .
To cut a long story short I didn't fill the new oil pump before fitting it (must've missed that in the Haynes), so is there a way of rectifying this without pulling the engine and stripping it down again?
I have been told taking the filter off and pumping oil into the little hole from my Wesco can, while pushing the car backwards (while in fourth gear) will draw oil back into the pump - I've tried this for half an hour this evening and managed to dribble a trail of oil in the street. Does this really work - should I persevere tomorrow with this?
Cheers.

[PGM]

I want to do this with my 40, was it difficult to get engine out and back in again and the rebuild itself? I'm pretty competent mechanically and have a decent workshop.

What sort of costs were involved and did you upgrade anything?

[Cooper1999]

About £600 for machining and bearings/gaskets.
I already had an SW5i kit (cam, duplex, valve springs, oil pump), clutch, pistons and bits and pieces for my kit car engine when the mini piston went pop. So probably £850-ish.
Just remember to learn from my lesson and fill the oil pump before fitting, or you'll be looking for the same answer!

[GTRMikie]

I'm not sure which hole you have pumped the oil into. The hole you need is the one where the link pipe from the oil filter to the block meets the block. Undo the banjo bolt that secures the link pipe to the block and pump the oil into the hole. Rocking the car backwards in top gear while you do this will help to prime the pump.

[Cooper1999]

Mike,
The hole I've been trying to pump oil into is the small one adjacent to the threaded oil filter hole in the centre. My car is an mpi, so the hole is at approx. 7 o-clock to the centre threaded hole.

[Cooper1999]

Thinking about it, I did put the O-ring in place between the gearbox and block.
But when I fitted the gasket (having three gaskets for this location did through me at bit at first!) I did notice the hole at this location was smaller than the diameter of the O-ring. That is - the O-ring will be being compressed between the bottom of the recess and the underside of the gasket. Could this be causing the problem?

[Nezquick]

Good work building the engine.
I built one for mine many many years ago when I had my first Mini - a 1340cc with straight cut 5 speed gearbox. It was an immense feeling getting the thing started after all that work and then seeing the figures I got on the dyno. It ran like a dream for many thousands of miles after that as well.

Sorry - can't help with the oil issue though!

[guru_1071]

Cooper1999 said:

Mike,
The hole I've been trying to pump oil into is the small one adjacent to the threaded oil filter hole in the centre. My car is an mpi, so the hole is at approx. 7 o-clock to the centre threaded hole.

your wasting your time trying to fill the pump through that hole (which is the pressure relief hole), with an mpi your a bit stuck as it doesn't have the handy hole that you can easily use to backfill the pump.

you could try removing the filter and back filling the ports, but I suspect that this would make a mess!


if you take the plugs out (so no compression) and crank the motor (with the filter refitted) for 5 min (keep stopping to allow the starter to cool) the pressure should come up, but if all you have is a light then it only needs 7psi or so before it goes out.

if the pressure doesn't come back after 10 min or so, then you have to assume there is a problem - ive never, ever seen a freshly rebuilt motor magically find decent pressure after this much cranking!


normally when you crank with the plugs out you can hear the engine note change as the pressure ramps up.

good luck!

[Cooper1999]

Ended up pulling the engine, filling the pump and refitting.
Engine got oil pressure, runs nicely (with only a slightly gruffer idle - SW5i fitted). Can't wait to drive it!
But I'll have to - the water pump gasket is leaking! Oh well....
Still chuffed that it works, and sounds great.