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TR2/3/3A Oil pump question

Hello John

Thank you.
Good to know that the hot bath is not destructive to the bush.
I will take a look at the clearance on the washer and make a little more if necessary.

David
 
The cheap modern gauge read about 5lb lower than the TR gauge.

I think that I will order a sump gasket and oil pump gasket then check out the pump and bushings.

David
 
I think I lost track of the goal here. Is it that the pressure is too low? If it is, then adjusting the regulator on the filter base is the way to go. I set mine using my air hose pressure regulator. Air flows easier than oil, so I set it just about 65psi on air. Sure enough, is sits right on the desired 70 psi on the car! If you reach a point where the spring is bottomed, valve closed, and the pressure is still low, then you have an excessive flow problem. Still, until you have tried to adjust with the regulator, you cannot be sure of the second condition.

Also, every filter base I have rebuilt (and I have, like 3 ready to go), the ball and seat in the regulator were corroded. They all required new balls to properly set the pressure without over-flowing oil.
 
I agree about checking the ball and seat, as that is another potential leak spot. But the function of the relief valve is to set the maximum pressure, which has been described as being just about right (70 psi). The relief valve should be already fully closed at idle.
 
Hello John

An update.
Oil pressure on start up is 70+ which drops a bit as it warms up. After a drive of about 25 miles the pressure is down to 50ish and at idle it is below 20.

I can remove the PRV and check for ball corrosion and the condition of the seat. I do have a spare so I can swap them out if I needed.

Maybe being super sensitive to the oil pressure readings.
David
 
I took the PRV out and took a look at the ball and seat. Both looked OK so I set up an air tester so I could see what was happening. Both the PRV from the car and my spare leaked despite having corrosion free balls and seats free of damage.

I had some valve grinding paste and made a wooden grinding tool and attempted to clean up the seat. That did not seem to make much difference I decided to try lengthening the spring as the adjuster was bottomed out. With a little experimenting I got the right amount of spacing above the spring to hold air at 70lb but blow off at 75.

Running the engine I have a higher pressure now. 80lb when cold but I think my gauge may be reading high by about 5lb. Have not driven yet but will report the results.

David

Pressure release valve setting e.jpg
 
Nice Job David, I wondered how someone could test, repair, and adjust those things. I always felt unsettled around them because I figured that one of the P.O’s at some point fiddled around with it. I plan on starting my motor this week and that is good information to have on hand.
steve
 
Hello Steve

I had the adjustment bottomed out and it was blowing off at 55 to 60lb It also had a leak. Thinking about it later I feel that a small disc of 220 or finer wet and dry on the end of my pointy stick might have done a better job of cleaning up the seat.
Make sure to clean all the abrasive out when you are finished.
I added a 4mm socket head screw to increase the amount of compression I could get on the ball. The screw slid inside the spring and the head fit in the adjuster. With this setup I could get the pressure up over 80lb and adjusted it down and locked the adjuster

David

PRV2.jpg
PRV e.jpg
 
I'm sure you noticed the factory used a lead seal around the adjuster after It was set. I just used a couple wraps of thin solder...and it seems to still be sealing well after several years of sitting/operation.
 
So that is what is around the thread. Looked like a mushed washer.

I think I will reduce the setting about 5lb as it is above 80 when I first set out driving.

David
 
Update.

Took the oil pump out and sanded the end plate as there was some wear in it. Checked the clearance in the pump rotor and that was good. That did not make a difference to the oil pressure but I did end up with an oil leak between the pan and block. I had struggled to get the pan on and scraped the gasket sealer off. So I had to get the oil pan off again.

While I had it off the second time I removed the oil pump and replaces the gasket between the pump and block and used a little sealer on the gasket.

The oil pressure seems to be better now. About 20+ at idle when hot and 50+ when driving at 2500 RPM.

David
 
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