TA Oil Pressure problem

[Phil Dadd]

I have just installed my rebuilt MPJG engine, with the plugs out, I tuirned it over about 3 times, checked and primed the oil pump, checked the oil filter and found that this was full. We took the pipe off the top of the oil pump and found that this is pumping oil.
But; there is zero oil pressure at the gauge and no oil running through the external pipefrom the bottom of the block to the head. I removed the oil filter and can get some oil to run through the outlet port that goes into the engine --- not a lot, but some. I am not prepared to run the engine until this is fixed. Any ideas?
Thanks,
Phil TA2982 Sydney Australia

[Gene Gillam]

Phil,

It takes a bit to get the oil pump pumping and the oil flowing. Did you spin the engine over on the starter motor with the plugs out? It can take several bursts of up to 20 seconds with the starter to start registering pressure on the gauge since you've got to fill all the oil galleries in the engine as well as the external tubing and filter.

This won't hurt the engine, by the way.

Gene

[Phil Dadd]

Gene, Thanks for your early response and suggestion. I am sorry to say that the frustration continues, although I am now pretty sure that the oil pump did not prime. Having decided this I pumped oil through the engine via a pressure tank. This shows oil through the Rockers and overhead gear, as well as showing oil pressure. I then put a vacuum hose on the external pipe that runs from the bottom of the Block to the Cylinder head -- but could not achieve any result. The idea was to pull oil through the pipes and, hopefully, like a capillary action I would have oil and pressure. Again no Success! I then dismantled the oil pump, packed the gears with vasoline and then topped up the pump with gear oil. Still no pressure !
I have been working on these cars since the 1950's and at this point in time have no idea what to do next. This is the second complete engine rebuild in the years I have owned this particular car. I figured that I may have another 10 years of driving, so rebuilt the gearbox, diff and ancillary running gear. Unless i can overcome this problem, there may be a TA for sale! I also have a Three Litre Alvis, but the MG has been a part of my life and getting rid of it would cause a riot within the family.
Kind Regards,
Phil

[phil cassie]

Good evening Phil , I'm in Melbourne. I had a similar problem with priming.I tried the Vaseline trick without success. The method I used was to feed oil into the outlet side of the pump with the plugs out,put the car intop gear and push it backwards a few engine revolutions. This primes the pump instantly. When you hit the the starter with the oil line disconnected it should fill your boots with oil before you can move your feet.If you pressurised the system as per your post all bearing surfaces should be adequately coated . At starter motor revs no damage is done.Make sure your oil filter is full, reconnect oil lines and try the starter pressure should be almost instantaneous. Phil TA 2833

[Phil Dadd]

Thanks Phil, A couple of questions; my car is still on jack stands. Do you think I could get the same result by putting the car in gear and turning the rear wheel? Should I leave the vaseline in the gear pump or clean it out? Should I disconnect the oil lines or have these bolted into place whilst "priming" the pump? Phil TA 2982

[Steve Simmons]

I don't know if the TA will act the same as TC, but the last time I rebuilt my engine I couldn't get the Vasoline trick to work like it did the time before. Nor did pressure seem to do it. So I poured oil into the output on top of the pump with a funnel, then cranked the car and within seconds I had pressure.

[phil cassie]

Good morning Phil. Yes you should be able to turn engine over by rear wheels. If not you may have to drop it off stands and push car backwards. When I first tried this method to prime I just left the Vaseline in. Leave oil lines disconnected to see if you have success (oil in boots) I use an oil gun tofill theoil pump but an oil can would probably do.If the pump is full of Vaseline you will only need enough oil to fill the air pockets in the pump.But beware it does make amess of your nice clean floor. Phil TA2833

[Gene Gillam]

I've primed the pump by putting the transmission in reverse, jacking up one rear wheel (if both rear wheels are off the ground, one of them will have to be held or the differential will allow it to turn and not the driveshaft - path of least resistance). Be that as it may, the pressure tank method should have primed everything! I remove the line going to the oil pressure gauge and attach the pressure tank to the outlet. By the time I've pumped 2 qts of oil in everything is full and when I turn the engine over with the starter (plugs) out the pressure registers almost immediately.

[mgtamike]

I managed to reassemble an oil pump with the gasket flipped over.
Gasket is symmetrical except for the outlet hole, so fitting it wrong way blocks the outlet.
No attempts at priming would fix that!!

[Phil Dadd]

Gentlemen, my TA now has oil pressure, a reading of 59psi. I would like to thank each one of the contributors for your assistance and wise counsel. My first error was an assumption that the pump was actually pumping oil --- it was not. I had just had the engine professionaly rebuilt by a company with impeccable credentials, hence I had not considered that they may have been in error. The problem was caused by the oil pump gasket which they had cut, not having a hole for the oil outlet, hence it didn't matter what we did, there was no way that the oil could be picked up and passed through the engine. Thanks Mike for this clue! As I had followed everyone's advice, it is unlikely that any damage was done, but in the event of anything occuring in the near future, I have the offending gasket plus a history of the work done to research the problem. I now have about half a gallon of oil on my garage floor, chipped and damaged paintwork on the new engine, together with some wisdom which I have accrued through this exercise. Thank you sincerely for your advice and the manner in which you responded to my plea for help.
Phil TA2982

[Gene Gillam]

Glad you got it figured out, Phil and congrats to mgtamike for the magic fix!

[Steve Simmons]

A home-made gasket missing a hole. It's always something you never considered. I'll try to remember that one!