spmdr
Diamond Level Sponsor
This could go in the Stock world.... but NEEDS to be done to a Race Engine.
In the past, there has been quite a bit of discussion
about the problems with the Alpine engine Oil Pressure
Relief Valve.
Here is one thread:
forum.sunbeamalpine.org
The problem is, the end result was a bit inconclusive.
So I am picking up the subject.
I too have had the OPRV stick open and closed!
...too many times!
Time to try something different.
upon disassembly, I found the piston was galled.
I wanted to try a ball bearing to replace the piston.
Looking closely at the valve refreshed my memory about some
unexpected details.
I concluded the OEM valve is a bit of a controlled leak,
even when closed, it does not seal very well.
The piston does not seal against it's face.
The inner sleeve of the valve housing has notches.
And the piston diameter (.435 Dia) is not a real snug fit
in the valve housing.
The replacement Ball bearing (.4375 Dia ) is a better fit.
The original spring is too long to use with the ball.
I found a shorter, stiffer spring at the Hardware Store.
The spring is a #136, with 10 turns of .056 wire.
I put the new ball and spring together with a single flat washer
to give a little more pressure.
so far it works correctly.
Time will tell.
DW
In the past, there has been quite a bit of discussion
about the problems with the Alpine engine Oil Pressure
Relief Valve.
Here is one thread:
Oil Pressure Regulator Questions
My dad's '65 has some oil issues...specifically the oil pressure regulator is junk. He was planning to modify it with the screw but it got a bit damaged during disassembly. After looking at it, I see why it was made the way it was but that reason (low price at high volume) doesn't much matter...
The problem is, the end result was a bit inconclusive.
So I am picking up the subject.
I too have had the OPRV stick open and closed!
...too many times!
Time to try something different.
upon disassembly, I found the piston was galled.
I wanted to try a ball bearing to replace the piston.
Looking closely at the valve refreshed my memory about some
unexpected details.
I concluded the OEM valve is a bit of a controlled leak,
even when closed, it does not seal very well.
The piston does not seal against it's face.
The inner sleeve of the valve housing has notches.
And the piston diameter (.435 Dia) is not a real snug fit
in the valve housing.
The replacement Ball bearing (.4375 Dia ) is a better fit.
The original spring is too long to use with the ball.
I found a shorter, stiffer spring at the Hardware Store.
The spring is a #136, with 10 turns of .056 wire.
I put the new ball and spring together with a single flat washer
to give a little more pressure.
so far it works correctly.
Time will tell.
DW
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