Luggers and Napa auto parts

[DDW]

Is the relief valve a piece of metal like the clicker the nun used in class?

Pretty much what I found in the NL branded filter. But perhaps more important is where the relief is located. The job of the valve is to bypass oil around the element, if the element has too much pressure drop from clogging. The theory is it is better to have unfiltered oil than no oil.

A relief valve at the bottom, means the oil comes into the filter, washes over the dirty side of the element, then through the valve to your bearings. You are getting not just unfiltered oil, but unfiltered oil with everything the filter has caught so far mixed in. With a top relief valve, unfiltered oil enters the filter and then immediately exits via the valve, without first washing the dirty side of the element.

Properly designed and maintained, the valve really should never open, but most filters have them for a reason.

 

[Steve DAntonio]

At the NL training a couple years ago Bob Senter specifically mentioned that NL had their filters manufactured to a spec they created. They found that generic filters didn't meet the needs of their application. Something about the relief valve? I don't remember the specific reason..

An excellent training opportunity for those who want to invest the time.

That is correct, NL is very demanding when it comes to the parts they will use. Their oil filters have an uprated bypass valve that doesn't open when the oil is cold, which would otherwise allow accumulated and unfiltered debris to enter the oil gallery. Also, be careful with spin on filters for transmissions, the pressure on a trans is high, in the region of 300 psi. Some after market filters cannot handle it, they will leak or burst.

I otherwise like NAPA Gold and WIX filters (Donaldson is the Cadillac of filters).

I visited NL's production facility a few times, as a guest of Bob's, I was amazed at how many parts they removed and returned from new engines they purchase from Deere, Toyota, Kubota and others, adding their own replacement parts, which are then used to make Luggers and large NL gensets.