Oil Filter Top Screws Help. Dirty or Clean

[Pilotman]

Can anyone tell me what the screws on the top of the oil filer are for. Im assuming that they are for a pre and post filter tap but need to make sure. I am installing a Spinner Model 25 filter system and am figuring where to get the feed line from. I dont want to T off of the turbo lubrication line incase of starving issues. Please help!



Thanks Guys.

 

[Pawpaw]

Those plugs are both pressure ports on the dirty side of the factory oil filter. Either one is a good location to use for feeding your bypass filter, but you'll have to find somewhere else for the return.



The oil filler cap is a popular (and easy) place for the return. Some guys are using a second, unused turbo return port. It's supposedly plugged off and you can get the fitting from Cummins.



Maybe someone else will chime in with more info on the return.



Bob

 

[Pilotman]

Thanks for the info there. Im still looking for a place to get the turbo oil return line.

On the spinner filters you must have a return line blow the filter as it is gravity return.



Thanks again,

 

[nickleinonen]

Those plugs are both pressure ports on the dirty side of the factory oil filter.

both those plugs on top of the filter pad are on the clean side of the lube oil filter. in the FSM under engine > lubrication you can see the drawing of the engine, and the zoomed cutaway of the filter pad showing oil flow. center is clean, center feeds those plugs



all the 3rd gen manuals show it

 

[Pilotman]

Would you have that drawing I could take a look at?



Just ordered the the tubes for the oil return.



Thanks for the time.

 

[Nate]

Yeah those are both clean. Why would you pump dirty oil into the turbo?

 

[Pilotman]

Its not for a turbo, its for a Spinner Centrafugal Filter. The filter says it should be on the dirty side but can be on the clean side. The turbo line off the side has nothing to do with the two top ports as far as I can see from the outside. So now we have a debate on if the top two ports are pre-filter or post-filter feed.



Thanks again guys.

 

[nickleinonen]

#ad

 

[Pilotman]

Thanks for the great picture! It is worth a thousand words by gosh. Just looking at the oil system, is there a good spot to get pre filter oil from on that side of the engine? Thanks for your help.

 

[nickleinonen]

i don't think there is a test port before the filter or lube oil cooler... will look into it though



***edit***



looking at the drawings and some pictures i have, the only way i can see you getting pressurized oil pre filter would be a custom fitting [banjo or metric to jic adapter] & oil pressure relief valve with the plunger having a small hole bored through it. but doing so would make the oil pressure relief valve [75psi factory] operate at a higher pressure. boring a hole through it would make it act like a boost elbow. . taking more pressure to pop open.



or, bore a large hole through the plunger [basically bypassing the internal pressure relief valve] and in the piping going to your filter, add an external pressure relief valve that dumps into your post filter line going back into the engine sump. post filter line would need to be big like a turbo drain line...



[gonna be much easier to plumb it post filter instead of pre filter... $0. 02]

 

[Nate]

I just noticied this is a 3rd gen... .

I'm not sure on the 3rd gen trucks, since I've never got up close to one, but on the 2nd gen trucks, there are 2 ports on the filter housing and one of the ports is used for the oil feed to the turbo.

Its not for a turbo, its for a Spinner Centrafugal Filter. The filter says it should be on the dirty side but can be on the clean side. The turbo line off the side has nothing to do with the two top ports as far as I can see from the outside. So now we have a debate on if the top two ports are pre-filter or post-filter feed.



Thanks again guys.

 

[nickleinonen]

I just noticied this is a 3rd gen... .

I'm not sure on the 3rd gen trucks, since I've never got up close to one, but on the 2nd gen trucks, there are 2 ports on the filter housing and one of the ports is used for the oil feed to the turbo.

on 3rd gen engines, there is 2 top test ports, and a turbo lube oil feed port on the back side of the filter head...

 

[Pilotman]

I can see that on my engine as well. What we are trying to understand is if the two top ports are pre or post filter ports. I was told by a cummins person that the one closest to the block was pre filter and the one furthest away was the post filter. This is for filter pressure diffrence I was told. I just cant find any literature that actually says it. Thats what we are looking for.



Thanks