Removing the oil pressure relief valve

[paulbell6]

Hi all, I need to remove the pressure relief valve and as expected I cannot get it to move (the engine is in situ), I was wondering if anyone has tried to remove it by removing the split pin and then cranking the engine over - as suggested on one of my previous posts. I have a large tray that I can put under the car but I am worried that the ensuing pressure may cause a bit too much mess. I was then going to increase the pressure relief point by adding a washer behind the spring.
Any tales of woe or great success would be gratefully received.

Many thanks as ever

Paul

[AlanD]

Hi Paul,

it has been done that way, then you have to catch it!! there should be posts on here discussing it, i think you have to manually prime it then, someone will explain better than me soon

Alan

[marshman]

Paul,
Put a big bucket or bowl under the engine, remove the split pin then start the engine for a second, as soon as it fires turn it off. You should find the cap, plunger and spring in the bowl with a small amount of oil - worked for me!

When you do get it out solder half a washer - end on - to the the cap. Then next time you need to remove it you can use pliers to pull it out.

Roger

[martin]

Paul,
Put a big bucket or bowl under the engine, remove the split pin then start the engine for a second, as soon as it fires turn it off. You should find the cap, plunger and spring in the bowl with a small amount of oil - worked for me!

When you do get it out solder half a washer - end on - to the the cap. Then next time you need to remove it you can use pliers to pull it out.

Roger

- - - - - or on the other side of the road Good luck ! Martin.

[flying farmer]

You only need a thin washer under the spring for a 10-15 psi pressure increase, first time I did it I used two washers and the oil pressure went off the top of the 100psi gauge and knackered it!

Neil

[paulbell6]

Thanks for the replies Gentlemen, everything duly noted.

Neil, when you say thin do you remember the actual thickness that you used please?

Kind regards

Paul

I should say that I have installed a pressure gauge and the pressure is quite slow to get to around 40 - 45 psi at tick over and does not move if I blip the accelerator, I did expect the gauge to mimic the rev counter to a certain degree.

[wilf]

If the gauge does eventually show a rise in pressure as revs increase, you probably just have a "slow" gauge. Mine moves in "jumps" anyway.

If you don't fancy trying to disloge the pressure relief valve as above, it isn't a big job to take out the whole pump, then you can have a good inspection of it. Does mean dropping off the downpipe.........

Not a bad idea to take the pump out and replace the O rings that seal it to the block, as they leak eventually anyway.

[paulbell6]

Hi Wilf, the pump is fully refurbished already, and I have removed the pressure gauge and tried it on an air line and it seems to work okay, so my feeling is that (with advice from on here) the relief valve spring has weakened thus allowing oil past meaning that the pressure takes more time to build. I think I have to try this method just to eliminate it as a problem, but who knows! fingers crossed.

Regards

Paul

[wilf]

Always good to eliminate possible causes.

While you are down there, empty the oil out of the capillary line to the gauge. Thick, cold oil in a thin tube will dull the gauges response. It will work perfectly happily on air.

[paulbell6]

Thanks Wilf, good advice.

Paul

[paulbell6]

Good evening all, just a quick update on my oil pressure situation. Pulled the split pin out of the pressure relief valve and cranked the engine over but still the valve would not dislodge! Took the pump off and removed the top plate to reveal the relief valve, and after a fight (there was only going to be one winner) I managed to remove the plunger, spring and cap. I assume that the cap was difficult to remove due to having a new rubber "o" ring fitted. Inspecting the plunger didn't show any signs of wear so it was all re assembled. This time I fitted an M10 stainless washer between the cap and the re fitted split pin in an attempt to increase the oil pressure. The washer thickness was 1.2mm. Having refitted the pump and cranked the engine the slow response in the oil pressure gauge is still present but I would have to say marginally higher at tick over.
i suppose now I have the option to add more washers to increase the pressure so I think I am heading in the right direction.
One thing that springs to mind is that i am initially using Halfords oil which I intend to change to Valvoline at a later date, and maybe this does not produce as much pressure as a better quality oil would do.

Your observations would be most welcome

Regards

Paul

One bizarre outcome of this work is that I have now lost the hand brake on light in the warning cluster. What next!

[staginhiding]

Hi Paul
Are you using the Halfords 20/50 oil..
Increasing the pump pressure will give you a false sense of security if you have a problem elsewhere..

Sam

[paulbell6]

Hi Sam, yes it is 20/50 classic motor oil. I am really just trying to get the newly fitted gauge to work as it should. Wish I had never fitted it!
The Topaz?

Regards

Paul

[staginhiding]

The Halfords 20/50 should be fine..
Is it a good quality gauge..
Dont ever wish you hadn't fitted it,its essential for peace of mind..
Just need to get to the bottom of it.
You need to check the gauge to make sure its working correctly..I'm not sure if there is an easy way to do that..anyone else ???

[milothedog]

The only true way to see what's happening is use one of these which is calibrated, I think I paid about £80 a couple of years back.

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Ian