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MG MGB GT V8 Factory Originals Technical - Very High Oil Pressure

Filled the radiator and was going to go for a spin for the first time in three years, but cranking it again for the fourth time since rebuild, it blew out the O-ring on the oil filter. I was looking at the oil pressure gauge and it ran up to at least 100# and fell off to just a couple of pounds and oil all over the floor again.

Has anyone had experience with the Flotec oil pump housing as shown on page 28 of the "How to give your MGB V-8 Power. I do not think the gears were changed on the pump. The Flotec has two bolts on the back of the cover. I have never had any experience on this issue and any suggestions would be appreciated. I think someone said you can change springs on the cover to change the pressure. Not sure what to do, but really tried of mopping oil off the floor and supporting Walmart with oil purchases. Any suggestions are really needed, PLEASE HELP!!!!!
Jeff Howell

It's hard to help some one via a post without seen what you have.

The only problem I can see from here(magic) is that you either have pressure relieve valve stock or you have the wrong spring in the pressure relive valve.

100 psi is to much.
Look at your pump and see if you have a nut and a screw in front above the filter. If you then then back off the screww two full turns and lock.
Remove your distributor and find a dummy distributor and turn it with a 1/2 drill and check your oil pressure. If you 1/2 drill is slow the oil pressure should read 30 to 45 (idle pressure) If your drill is a fast one then it should read 50-60.
Check it first as it's right now with the drill, this way you can get a base line.

If you do not have the adjustable pump, then removed the big nut and make sure the sporing is not binding, if its invetigate why. If the spring is to strong it will have high oil pressure, less spring less pressure.
Sometimes pumps have a shim under the spring remove and test with the drill making sure you are turning the correcdt way.
Bill Guzman

I reckon Bill has made the only diagnosis he could - I don't recognise Flotec but if the pump is similar to the OE, the pressure relief valve is on the pump face (after end) -Moss used to sell a tighter spring which increased pressure by about 4 lb. My guess is, yours was jammed shut.

As far as changing the gears on the pump - Rover put bigger gears into the SDI in order to increase volume - so long as yours actually filled the pump body - you don't have a prob (and you don't get 100psi from a pump which is not working).

Your target pressure on startup is 45psi - 20 at idle when hot.

Roger

I had the same thing happen to my engine at it was a small drop of loctite on the pressure relief valve that caused it to stick. When the o-ring blows on the oil filter it makes a real mess.
Jim Miller

Thanks for the feedback. Removed the output tube from the oil filter, no blockage. Removed the large bolt on Flotec and removed the spring and did not see anything. Removed the spring, reinstalled bolt, removed the distributor and spun up the oil pump. No pressure on the oil gauge. Reinstalled spring and spun up the pump and the drill did not labor as before. Had son hold drill and what do you know, 50-55# of oil pressure. Reinstalled distributor and cranked engine and the oil pressure was 50-55# of pressure. I guess when I spun up the oil pump without the spring it broke lose the valve.

Many thanks for the feedback. Look forward to see you all in Townsend, TN for the V8 meet!

Jeff Howell
Jeff Howell

" Look forward to see you all in Townsend, TN for the V8 meet!"

We wish !!
Roger

RMW

This thread was discussed between 15/04/2006 and 18/04/2006

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