• Hi Guest!
    You can help ensure that British Car Forum (BCF) continues to provide a great place to engage in the British car hobby! If you find BCF a beneficial community, please consider supporting our efforts with a subscription.

    There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Subscribers don't see this gawd-aweful banner
Tips
Tips

MGA Priming the OIl Pump... MGA 1500

ronzet

Jedi Knight
Offline
Good day all,

I have been trying to find an document that I once read that outlined the priming of the oil pump after a rebuild of an A 1500 engine.... to no avail...

Anyone possess this bit of knowledge or am I losing my memory completely??? /bcforum/images/%%GRAEMLIN_URL%%/cheers.gif
 
Hello Ron,

I have read that pumps benefit (not just MGA's) from being filled with petroleum jelly when the engine is assembled but I have never tried it.
Are you having a problem getting oil pressure to build up? I would suggest, if that is the case, that you open an oil gallery and pump oil into it to back feed the pump with oil. I know some people go to the trouble of removing drive shafts etc and driving the pump with a drill but again I have never done that. I would just crank the engine with the plugs out, until it pumps. I find that I can hear the pump start to work before any pressure starts to show. If none of this works after a few minutes then I would drop the sump to check the pump.

Alec
 
You could always pick up or borrow a cheap pre-oiler. Run that through the system for a few seconds and you're good to go.
 
piman said:
Hello Ron,

I have read that pumps benefit (not just MGA's) from being filled with petroleum jelly when the engine is assembled but I have never tried it.
Alec

/bcforum/images/%%GRAEMLIN_URL%%/yesnod.gif The prescribed method for TR8's, and I can guarantee it works (assuming there's oil in the pan, and the pump's good).

Mickey
 
piman,

Good morning. Nice to hear from you.

I have not yet fired the engine up, but darn close, ergo, the query. The rebuild was complete along with a new oil pump. I don't know if there is a problem yet... Just being cautious. /bcforum/images/%%GRAEMLIN_URL%%/smile.gif

I have rebuilt dozens of engines over the years and never bothered with priming the pump. However, the memory of this article has played havoc in the back of my mind.

The engine is in place without the petroleum jelly in the pump and I would rather not drop the pan.

I will pour oil in the back feed and pray...

Thanks for the suggestion /bcforum/images/%%GRAEMLIN_URL%%/cheers.gif
 
Ron -

With a new pump already installed and the engine ready to start, I believe I'd go with pulling the spark plugs and carbs and spin the starter over a bit until you "see" oil pressure on the gauge, or maybe you can remove the oil pressure sending unit and see oil pumping out there. A bit messy, but at least you'll know...

Let us know how you make out.

Mickey
 
I know this is a problem on some B's, don't know about A's though. The oil pump gasket will fit two ways. One is correct, the other way blocks a hole so the oil can't flow.
 
Maynard,

Oh great.. now I have something else to worry about.. /bcforum/images/%%GRAEMLIN_URL%%/wall.gif

/bcforum/images/%%GRAEMLIN_URL%%/cheers.gif
 
Mickey,

Thanks for the suggestion.... I do have the oil pressure gauge hooked up and will crank the engine over until I see some pressure...or better yet, to eliminate anything but the basics... I will take the messy approach and disconnect it looking for oil to spurt all over my nicely painted engine compartment... /bcforum/images/%%GRAEMLIN_URL%%/rolleyes.gif

/bcforum/images/%%GRAEMLIN_URL%%/cheers.gif
 
ronzet said:
Mickey,

Thanks for the suggestion.... I do have the oil pressure gauge hooked up and will crank the engine over until I see some pressure...or better yet, to eliminate anything but the basics... I will take the messy approach and disconnect it looking for oil to spurt all over my nicely painted engine compartment... /bcforum/images/%%GRAEMLIN_URL%%/rolleyes.gif

/bcforum/images/%%GRAEMLIN_URL%%/cheers.gif

Well, there is THAT little item! /bcforum/images/%%GRAEMLIN_URL%%/jester.gif
 
/bcforum/images/%%GRAEMLIN_URL%%/lol.gif

Well.. yes, there is that.. /bcforum/images/%%GRAEMLIN_URL%%/jester.gif

I'll let ya know...
 
Ron - the oil pumps in the B series engines don't need priming the way they do on the old XPAG engines used in the T series cars do. Having a TD, I made up a pressurized priming system that works equally well on the MGas and early MGBs. It consists of a 1.5 gallon garden sprayer with the nozzle replaced with a 'T' fitting as used on the later MGBs to connect the flexable oil pressure pick up to the ridgid line to the gauge and to the pressure switch, which is part of the anti run-on circuit. I insert the 'T' in place of the straight through coupler with the hose from the garden sprayer attached, put 4 quarts of oil in the container and then pump up the pressure of the sprayer and wait until all the oil has been pumped through out the lubrication system, including the pump and into the sump. You can even watch the oil pressure gauge and see the pressure being used to push the oil in. When it is done, I reconnect the original adapter in place, spin the engine a bit with the starter with the plugs out (probably unecessary) to insure that there is still oil pressure, install the plugs and start the car. The gasket problem spoken of above, involves the 5 main bearing engines for the later MGBs. There were two different pumps used and the gallery holes were different. The gasket kits had both style pump gaskets supplied and if the wrong one was installed, no oil pressure was developed (guess how I found that one out).
Cheers,
 
David_DuBois said:
The gasket problem spoken of above, involves the 5 main bearing engines for the later MGBs. There were two different pumps used and the gallery holes were different. The gasket kits had both style pump gaskets supplied and if the wrong one was installed, no oil pressure was developed (guess how I found that one out).
Cheers,

I remember finding two similar gaskets and reading about this in the B Series Engine Data book. I made sure I had the right one then cut the extra one up into little tiny pieces :smile:

I pumped oil down the thin braid hose using an oil can, but didn't bother to pressurize it. Pulled the plugs and cranked; after about 5-10 secs, I had pressure.

Don Garlits (the drag racing legend) once told me to always run my B-series engine at least a quart over full, as it tends to not drain back and may starve the pump . He also told me to paint the inside of the block with Glyptal to help the oil return to the pan faster. I do the former but did not do the latter. He swears a factory rep suggested this to him on a visit to England.
 
I think that priming a A-series (Spridgets) or B series MGA/MGB) is the only way to fly, as sometimes they will get a air lock and take freaking forever to get pressure. On the rear oil fitting on the back passenger side of the block, the one going to the oil cooler or oil filter depending on the car and set up you have, (not the oil pressure gauge line) with the line removed insert a small funnel, pour a small amount of oil in it, then rotate the engine by hand at the crank nut counterclockwise, it will suck oil into the pump, do this a few times until it looks like it slowing up on the sucking of the oil into the pump, you have now primed your oil pump, hook the hose back to the fitting, with the spark plugs out, turn over with the starter, now you should see pressure at gauge in 60-90 seconds.
 
HAp,

THANK YOOOOUUUUU.... /bcforum/images/%%GRAEMLIN_URL%%/thankyousign.gif /bcforum/images/%%GRAEMLIN_URL%%/thumbsup.gif

As I said in my original post I had read an article with that process in it.... You have been a great help.

Thanks again... /bcforum/images/%%GRAEMLIN_URL%%/cheers.gif
 
Scott_Hower said:
Don Garlits (the drag racing legend) once told me to always run my B-series engine at least a quart over full, as it tends to not drain back and may starve the pump .

Don may be the dragmeister but he isn't right on MGs.

There is no need to run over full on the MG engine and you will get windage loss if you do. You DO need to use a sump baffle to keep the oil down in the pan if you slalom or road race. Many American engines need restrictors to the top end or even fancier ways of getting oil back down (eg American Motors V8s), so maybe that was where he was coming from.

Vaseline? Never bothered and the thought of adulterated oil would bother me more than the possibility of the pump not priming. And don't use KY - I hear it's no f___ing good.... /bcforum/images/%%GRAEMLIN_URL%%/devilgrin.gif
 
Back
Top