Single oil pressure relief valve length, 60mm VS 63mm

[Ofir]

Hello all,
My case has Single oil pressure relief valve.
The length of the ~45 years old spring is 60mm, yet according the BENTLEY books it should be between 62-64mm,

I found NOS German relief valve spring, and the length is 63mm, per the book.

What's the difference I'll get in the engine by this 3mm difference between those 2 springs: old 60mm VS new 63mm ?

Oil pressure difference?
Oil temp difference?

Thanks!

[Mr.Duncan]

The newer longer stronger spring will be harder for the oil pressure to push down.

So when the oil is thick cold and high pressure it pushes the piston down, which allows it to go straight to the bearings and bypass the oil cooler.

when the oil is thin and hot and lower in pressure the spring and piston win and push up diverting the oil to the oil cooler THEN to the bearings.


Thus, installing a new Stock Stronger not worn out spring will direct the oil to the oil cooler sooner.
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[Ofir]

[Mr.Duncan]

Probably not.

If im correct since you do not have the 2nd valve like I do.

the oil either have 2 ways in your case.

To the bearings (pressure is made)

Or to the oil cooler (cools the oil) THEN to the bearings (pressure is made)

If you have low oil pressure this would be because the clearance in your bearings is wider, or your oil pump is scored.


In my DUAL relief case, my 1st valve controls the oil cooler (like yours)

My 2nd valve is on the back of the case which lets oil the oil escape, for example if i have too much pressure in my case, the 2nd valve would open and dump the oil from the lines going to the bearings into the sump.

In your case, if you had too much pressure this is what would happen.

It would have to squeeze out your bearings or blow up your oil cooler.




When i had a OLD worn out engine i install a stronger spring in the 2nd valve that would only open the oil to the sump at a much much higher pressure causing my oil pressure to go up.

More of a bandaid fix.


Read this thread. Its nice.

http://www.thesamba.com/vw/forum/viewtopic.php?t=280293
_________________
(Owner) www.vintagecarleds.com

Red 1971 Squareback Thread
Red 1966 Beetle Thread
---------------------------------------------------
1971 Green Super Beetle (sold)
1966 Ghia (sold)
1971 Blue Super Beetle (sold)
1966 Java Green Std Beetle (sold)
1971 Red Squareback (sold)
1966 Red Beetle

[Ofir]

I have very good oil pressure, the engine has low miles on it, post rebuilt a few years ago. it's stock 1600cc, single relief case.

However, the green light never turn on, nor flicker when the engine is hot on the highway.

I use 0-30 BRAD PENN

Thanks again for your answer!

[Mr.Duncan]

[Mr.Duncan]

update

It appears the single relief valve also lets oil return to the sump if its too high pressure.

_________________
(Owner) www.vintagecarleds.com

Red 1971 Squareback Thread
Red 1966 Beetle Thread
---------------------------------------------------
1971 Green Super Beetle (sold)
1966 Ghia (sold)
1971 Blue Super Beetle (sold)
1966 Java Green Std Beetle (sold)
1971 Red Squareback (sold)
1966 Red Beetle

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