Discussion
Oil pressure relief valve stuck? Try replacing the plunger type with ball and spring.
Oil pump - did you put the gasket in the right way round - otherwise you've blanked off the feed gallery hole (common mistake). Was the pump primed when you built it (usually fill it full of cam lube that won't drain away)? If the pump is trying to pump fresh air it have no suck (if you excuse the pun) and not generate pressure even if the unit turns over...
Crank the motor over on the starter with the plugs out to get the oil pressure up. Do not start it up, or you'll undo all the good work you've put in so far...
Good Luck.
Oil pump - did you put the gasket in the right way round - otherwise you've blanked off the feed gallery hole (common mistake). Was the pump primed when you built it (usually fill it full of cam lube that won't drain away)? If the pump is trying to pump fresh air it have no suck (if you excuse the pun) and not generate pressure even if the unit turns over...
Crank the motor over on the starter with the plugs out to get the oil pressure up. Do not start it up, or you'll undo all the good work you've put in so far...
Good Luck.
Edited by FWDRacer on Thursday 20th March 10:34
Sounds like it has seized in the bore - these can be a bugger to free off. It sounds brutal - but if you have either a new plunger (wise investment) or plan to replace with ball and spring (these aren't 100% failsafe either), get an Easiout or failing that drill and blind tap the plunger to get in and remove it. Try and avoid getting swarf in there (main oil gallery - although it will go through the filter before reaching the pump).
You will find that the plunger will be heavily scored but the actual bore in the majority of cases is fine. A new plunger should do the trick. A trick is to machine a couple of flats on the cylindrical surface (not right the way down) to allow any sh!T to get pumped out and not seize the plunger in the bore. Before anyone gives me a rollicking for not suggesting the ball and spring 100% to replace - I've had problems with them feckers too
Again.. Good luck.
You will find that the plunger will be heavily scored but the actual bore in the majority of cases is fine. A new plunger should do the trick. A trick is to machine a couple of flats on the cylindrical surface (not right the way down) to allow any sh!T to get pumped out and not seize the plunger in the bore. Before anyone gives me a rollicking for not suggesting the ball and spring 100% to replace - I've had problems with them feckers too
Again.. Good luck.
Put the car in gear and push it backwards whilst pouring oil into the oil output hole in the block. If you have an oil cooler, take off the input pipe into the cooler and pour oil down that pipe whilst pushing the car backwards.
Personally I have never liked the ball bearing type oil press relief valve and always use the plunger type. I did once have one stick open, so now I always polish the outside diameter with 1200 wet and dry, followed by a good metal polish to achieve a smooth finish. Make sure the housing is free from swarf or other muck.
In fact I did one of these just yesterday for a '67 Cooper 'S'.
It can be a problem to get the pump to prime and before the advent of 'assembly lube', I used to use EP90 gear oil as a pump primer to avoid 'drain down' prior to starting.
On a 970 'S' I had a few years ago, the drain down over the Winter was so bad that the pressure would not come up and I thought I had sheared the pump drive pin and stripped it all down, only to find that it was a poor build toleance pump.
The other problem is that if you use a pin drive pump on an 'S' block, the length of the shaft is different for the 850/998 blocks and for the 1275 it must be 0.230" longer (that's from memory). However, the Federal-Mogul catalogue lists the same pump for all engines and on a 1275 it just won't work properly. Sure it appears to engage and does so by about 0.030", but the load at cold start is high and the slot can shear off and leave no pump drive at all. I did write and tell them that their catalogue was wrong, but got no reply, despite sending a drawing as well. That was 3 years ago and it'still wrong.
The other oil pump problem is where you have had a 3-bolt pump (early 'S') and changed to a 4-bolt (like a Metro turbo pump). The extra drilling for the 4-bolt can break into the water gallery on earlier 1275 blocks which does not matter too much, except if you go back to the 2-bolt, which is all that's available in slot drive now, in which case the gasket land it small and 80 psi+ oil can easily pump into the water. I had this happen and cured it by drilling out the oil pump casing to take 4 bolts.
I hope all this helps.
Peter
Personally I have never liked the ball bearing type oil press relief valve and always use the plunger type. I did once have one stick open, so now I always polish the outside diameter with 1200 wet and dry, followed by a good metal polish to achieve a smooth finish. Make sure the housing is free from swarf or other muck.
In fact I did one of these just yesterday for a '67 Cooper 'S'.
It can be a problem to get the pump to prime and before the advent of 'assembly lube', I used to use EP90 gear oil as a pump primer to avoid 'drain down' prior to starting.
On a 970 'S' I had a few years ago, the drain down over the Winter was so bad that the pressure would not come up and I thought I had sheared the pump drive pin and stripped it all down, only to find that it was a poor build toleance pump.
The other problem is that if you use a pin drive pump on an 'S' block, the length of the shaft is different for the 850/998 blocks and for the 1275 it must be 0.230" longer (that's from memory). However, the Federal-Mogul catalogue lists the same pump for all engines and on a 1275 it just won't work properly. Sure it appears to engage and does so by about 0.030", but the load at cold start is high and the slot can shear off and leave no pump drive at all. I did write and tell them that their catalogue was wrong, but got no reply, despite sending a drawing as well. That was 3 years ago and it'still wrong.
The other oil pump problem is where you have had a 3-bolt pump (early 'S') and changed to a 4-bolt (like a Metro turbo pump). The extra drilling for the 4-bolt can break into the water gallery on earlier 1275 blocks which does not matter too much, except if you go back to the 2-bolt, which is all that's available in slot drive now, in which case the gasket land it small and 80 psi+ oil can easily pump into the water. I had this happen and cured it by drilling out the oil pump casing to take 4 bolts.
I hope all this helps.
Peter
Yep that helped me. I'd thought of the rolling-car-backwards-in-gear trick but didn't know if it was standard practice, or would work. Suitably reassured now.
Just have to mount the EDIS and coilpack for the Megajolt, make up the loom, then drop the engine in and I should be away. Oh and mount the oil pressure gauge, and make up a plug for the distributor hole, and put the grille back on, and get the mould off the steering wheel, and pump the tyres up, and reconstruct the exhaust, and get a new horn, and make sure the brakes still work and then I can start mapping the ignition. Still some way to go.
Just have to mount the EDIS and coilpack for the Megajolt, make up the loom, then drop the engine in and I should be away. Oh and mount the oil pressure gauge, and make up a plug for the distributor hole, and put the grille back on, and get the mould off the steering wheel, and pump the tyres up, and reconstruct the exhaust, and get a new horn, and make sure the brakes still work and then I can start mapping the ignition. Still some way to go.
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