1931 and 1932 Series 80/90 oil pump bypass valve spring

[drovak]

In both my '31 and '32 parts car, the oil pump bypass valve spring was corroded and not doing much good. 

 

For those still operating with an oil heat exchanger, this spring and plunger should be installed in case the oil is too cold and viscous to flow through the heat exchanger at normal flow rates.

 

For those that have bypassed the heat exchanger with an external loop, this valve and spring should not be necessary and could be left in or removed. 

 

For those that have bypassed it with simply capping off the block, it would be wise to remove the valve and spring altogether.

 

For those that plan to put a full flow oil filter in this circuit instead, having this valve operational may be a good thing in case the filter gets too clogged. Rather than the filter bursting and contaminating things down stream, the valve can bleed off some pressure and bypass the filter—just like modern cars, as I understand it. 

 

Anyways, I found what I believe are the appropriate springs at Lee Spring (LC 035EE 17S, 2.5 lb/in). I had to order extras lest I pay a hefty surcharge for my order, so I'm happy to sell my two extra stainless springs for $8 each plus shipping. I also have the music wire version (not stainless, LC 035EE 17M, 3 lb/in) which I don't anticipate using anytime soon, but I have two of those extra as well. 

 

 

For further clarification, this is for part number 1249500 in the master parts list. I have no idea what was used after 1932, if anything. 

 

[BuickTom87]

Any pictures where this goes. ? For some reason I’m drawing a blank 

[drovak]

Of course! Once you drop the oil pan and remove the pickup screen and tube, you have access to the valve and spring. 

 

 

 

 

[BuickTom87]

Ahh ok yes , my mechanic dropped the pan and replaced it for me as well . He said he had to match it up to other springs he had in his bin. 

 

Did you find a lot of sludge 

[drovak]

2 hours ago, BuickTom87 said:

Ahh ok yes , my mechanic dropped the pan and replaced it for me as well . He said he had to match it up to other springs he had in his bin. 

I'd be very sure the spring constant is correct. If it's too strong, it won't do much of anything. 

 

2 hours ago, BuickTom87 said:

Did you find a lot of sludge 

Had some goo in the spring area as seen in the photo for the '31, but not too much in the pan. Definitely not like the prehistoric dino goo in the '32 oil pan. But the spring certainly sits in oil that could turn to goo eventually as that's not the usual path for oil to take. 

[BuickTom87]

Yeah , I had a lot of gunk like a lot of gunk. Surprised it ran and the pickup screen was loaded