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CAT fuel filter

4K views 40 replies 12 participants last post by  chadw90 
#1 ·
I have the aftermarket CAT fuel filter kit. I've read that most people lube the seal with fresh oil or diesel, either is fine. But I was wondering how tight to tighten it. The filter printed on instructions say, don't fill it with fuel first?? and to hand tighten +1? How tight does everyone else do it? also I thought it was fine to put fresh fuel in so the pump doesn't have to fill it up.
 
#2 ·
Yeah, lube the rubber ring with diesel.
I went hand tight with a latex glove. Go tight enough it doesn't leak. Take for a spin and double check it after you park.

I just pulled off my 10k used Cat and had to use a slip joint filter wrench it was on so tight (that was me :spank:). I was worried it was galling on the threads, but nope, just on real tight and I don't remember lubing the ring :doh:

Oh, don't fill it with fuel. Bump the truck and let the pump run for 30sec after each bump. Do that a few times and it'll turn right over.
 
#3 ·
Ok thanks, I guess ill hand tighten it as much as possible then if it doesn't feel good, wrench tighten by feel

By bump do you mean turn the key and let the pump prime?
 
#5 ·
Yeah, bump means turn the key momentarily, just enough the starter turns and "bumps" the engine. It'll sound like you made the truck cough. You will hear the pump run after that.

Here's an example: https://www.youtube.com/watch?v=VnLBXqL5pc8
Skip forward, the bump is at 1:26
 
#7 ·
lol
Just in case, this is the filter lifesaver
 
#8 ·
I would not tighten it with a wrench. first time I changed mine I did it by hand as tight as I could get it and I about never got it back off! Had to go buy the filter wrench as pictured above. Also, I have never had a problem with priming mine. I have much more problem priming the system after changing the stock filter than after changing the CAT. usually just turn the key and let it sit a minute before I try to start it. :thumbsup:
 
#9 ·
I need to get some gloves or something then to get it tight as possible. Ive got the adapter that goes on the bottom of the filter and connects to the ratchet extension. works like a charm.
 
#13 ·
Gotcha, ive heard people say only use fresh oil though, obviously because it can get into the fuel
 
#29 ·
You shouldn't fill the filter because the whole point of using a 2 micron filter is to prevent unpolished fuel from reaching your CP3 and injectors.

Are you sure you want to just pour some ....whatever fuel straight in? completely unfiltered? out of some ....can or whatever?

I know that if you think of it like this you won't do it to your truck.:doh:
 
#17 ·
No clue, and this is me just being paranoid, but do i need to worry about draining the stock filter house and stock filter now that i have the secondary. Common sense says no but i like to have a second opinion
 
#19 ·
Is your Cat filter before or after the stock can?

The stock can maintains heating and WIF capability. Run a Baldwin 7977 in there, it is the best you can run in that location. You will need to drain the filter bowl to change that filter. You will need to drain it in the event you do get WIF too.

My Cat is after the stock can (horn mount GDP). When I changed the Cat filter I drained the stock can thinking it would suction back some of the fuel in the Cat head, but it didn't really clear it as much as I thought it would. The Cat is full and you'll get a bit of fuel spurt out when you crack the seal. So, lay out a towel if you want. I had a cardboard box laid out flat underneath the truck that caught the fuel in the driveway.
 
#20 ·
I just purchased this kit. Hope its an easy install.
 
#23 ·
What kind of oil do yall use for lube? Ive got lawn motor oil laying around haha. I think its just 2 stroke
 
#25 ·
The oil on the seal doesn't matter a whole lot really in the grand scheme of things. It is there to prevent the rubber from sticking upon removal. Also facilitates easy sliding when tightening down so it gets snug enough for a good seal.

When it comes down to it:

1. Snug new filter enough to not leak.
2. When removing be certain the rubber gasket comes off the base before installing the new one.
 
#27 · (Edited)
Shorts you were right, that thing was in good! I used 2 cycle oil to lube the ring, spun the new one on, hand tightened, drove some them hand tightened as tight as I could with some gloves on but no wrenching

Sent from AutoGuide.com Free App
 
#30 ·
Wouldn't putting this AFTER the stock setup be less work on the CAT filter? If you do it before, the CAT filter is basically filtering everything. After the stock, its a two step process from 7um to 2um. Before the stock, and is a 2um to 7um, which the 7um would always be clean. Am I missing something.
 
#31 ·
FSU, glad you got it done :thumbup: Yeah the filter seems to get tighter the longer it runs.


Wouldn't putting this AFTER the stock setup be less
work on the CAT filter? If you do it before, the CAT filter is basically filtering everything. After the stock, its a two step process from 7um to 2um. Before the stock, and is a 2um to 7um, which the 7um would always be clean. Am I missing something.

I prefer the stepped filtration as well, as do many others. It does allow for the most efficient use of a filter & it's media. Big to little with the flow. Kind of like watching the show Gold Rush. Except I haven't found gold specs in my filter yet. Though I should for the price of diesel, you'd think there's gold in it.
 
#33 ·
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#35 ·
You're welcome. The forum is full of buried treasure threads for all the questions you might have on your truck. Gotta dig, read, dig, read, dig, read, lather, rinse, repeat. You'll find info that works for you immediately and info that you need to keep for later on a issue that might crop up.
 
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