Oil Filter Relief Valves

[DavidBrough]

Does anyone know if there is a difference between the springs and plastic caps for the oil cooler bypass and filter overflow valves as I seem to have mixed them up and they both seem the same. I know that they break at significantly different pressures and wonder of this is determined by the filter housing casing shape as opposed to the springs and caps themselves.

[wwheeler]

I just rebuilt my entire oil filter housing including the relief valves. I used new springs and valves from MB. The caps I believe are interchangeable and are indicated as such by the parts listings.

The original valves were of two different materials in my early '68 M130. One was a phenolic/canvas (Micarta) material and the other was steel. The springs were also different. I believe I still have the old parts and tagged which ones went where. I also have the new MB part numbers. 

The new valves are of a slightly different design than the old ones and are plastic. The new valves are interchangeable. The new springs are still different part numbers. I hesitated whether to use the new plastic ones vs. the original ones simply based on material. I went ahead and used the new plastic ones. I think the size of the valves are the same (which is why the new ones are interchangeable) but the material is different in the old ones possibly because of the different relief pressures.

I hope this helps.

[DavidBrough]

Thanks Wallace, I think I will just order two new ones then I'll definitely know which is which.

[DavidBrough]

Hi Wallace,

Could you post the part numbers you have for the relief springs to help me locate the correct bits.

Thanks

[wwheeler]

David,
Here is the skinny on the valves and springs. I have attached two pictures of the original ones. I attached a pic of the restored oil filter unit so you know which valve I am talking about. BTW, I don't know how much these things changed from year to year. I know this is correct for an early '68 M130 motor. I also do not know the position of the overflow and  the bypass on the filter unit.

The reddish colored "mushroom head" valve is the phenolic or micarta material and has the shorter spring. This one goes on the front face of the unit that is next to one of the allen head mounting bolts.

The metal cone shaped valve is not aluminum as I said before, but is steel. It has the longer spring and goes on the bottom side (can't see in pic) below an oil cooler fitting.
New valves # from MB #601 184 01 32. Replacements use the same valve and seem to fit OK.

Original springs:
Phenolic valve on front face - 2-1/4" long with .058" wire diameter and .122" spacing between coils. # new from MB #002 993 39 01.   
Steel valve on side below oil cooler fitting - 2-7/16" long with .047" wire diameter and .080 spacing between coils # new from MB #002 993 40 01.
Both springs had a .500 OD but because the wire diameters are different, the ID are slightly different.
Unfortunately, I did not measure the replacement springs. I just installed them by the part number according to the EPC. I seem to recall that the lengths of the replacements springs were not that different.

I would definitely confirm this info with the Classic Center as it may change with the different models.

Hope this helps.