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Topic: 8.3 cummins filter confusion.  (Read 2033 times) previous topic - next topic

8.3 cummins filter confusion.

Quote from maz
I have a 99 coach with the electronic engine. It has a electric lift pump. I had been pre-filling the filter until last time I did it I noticed a note printed on the Fleetgaurd filter. It said something to the effect that the 8.3 does not require pre-filling. I think it says something about turning the ignition on for so many seconds or something to allow the lift pump to fill the filter. Tried it last time and it worked great. The engine did not even hiccup. I imagine this is only for the engines with the electric lift pump.

Mark

 Ok. So I searched the Beamalarm site and the search function on the fofums page. Realy didn't find an answer to a question. Also no answers in any of the several books that came with the coach. I looked.

  I'm not sure if the mechanical 8.3 has the electric lift pump or just what system it uses. I have the 2 new fuel filters and would like to change them out tomorrow. Am I going to do any harm by pe-filling them. I turned the ignition on and didn't hear anything that sounds like a fuel pump and I even opened the plastic peacock on the bottom of the filter ,  Nothing coming out.  So    I'm thinking I've got a mechanical fuel pump ?   

  I could just throw them on like the old 7.3 navistar and touch it off ,    Then let it shudder, shake, cough, spit and fart like the ford did but I REALY don't want to do that and besides it prolly wouldn't keep running either.

 Does anyone have the answer or know where I can find it.      Thanks
Robert and Susan
 1995 36' 280 WTBI 8.3 3060r
 1200 watts on the roof, 720 Ah of lithium's
 Build # 4637. Motorcade # 17599
        FMCA  # 451505
        18  Wrangler JLUR

Re: 8.3 cummins filter confusion.

Reply #1 –
I have the mechanical 8.3 and it has the mechanical lift pump located below the secondary fuel filter,I have always pre-filled the
fuel filters and it starts right up,yours most likely is the same setup.
96 U270 BUILD 4810
85 380SL
Drummonds TN.

Re: 8.3 cummins filter confusion.

Reply #2 –
You must prefill the filters on the 8.3, the fuel pump does not have enough lift to do it easily.  You can CRANK and CRANK til it starts but you will run down the batteries
 and overheat the starter doing it.  And NO, I will not detail how I know this.
Gary B

Re: 8.3 cummins filter confusion.

Reply #3 –
Bob,
As stated above, your mechanical 8.3 has a mechanical lift pump.  Makes sense...right?  You actually DO have a pump that can be used to refill the fuel lines and filters after changing them, but you won't want to use it.  It is built into the mechanical lift pump.  I'll post a few photos below.  Two of them show the old and new pump from when I replaced mine.  The others show different views of the pump mounted on the engine.  It is on the side of the block, passenger side, down low and kinda hard to get to.

new lift pump made a BIG difference

There are 2 "barrels" on the pump.  The top one has in and out fuel fittings, and a pushrod sticking out the side.  The pushrod is activated by a lobe in the engine as it rotates, and works the pump.

The bottom barrel has a black rubber cover on it.  You can push on the cover, it will go in and out, and it will work the pump "manually".  This will refill your fuel lines, and pressurize your fuel system, after changing filters.  Problem is, the manual pump is so hard to get to, and so awkward to operate, that it is practically useless.

So it is easier, and cleaner, to just pre-fill the filters with CLEAN fuel, screw them on, and crank the engine.  I warm up my engine before I change the filters, then swap them out.  Mine has always started right up - never been a problem.
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: 8.3 cummins filter confusion.

Reply #4 –
Chuck,
What kind of wash and wax do you use on your engine? Mine just don't want to get or stay that clean!!
Nice pics .... Thanks for posting.
Justin & Cathy Byrd
1995 U280 "Old Faithful"
36' Build #4673
C8.3 Cummins
Allison MD3060R 6 speed - retarder
Powertech 10KW  4cyl Kubota

Re: 8.3 cummins filter confusion.

Reply #5 –
On my 8.3C, I have found by pre filling the primary filter, priming, starting and then changing secondary filter it starts with less cranking.
John
1998 U270 34'

Re: 8.3 cummins filter confusion.

Reply #6 –
Quote from: FourTravelers –
Chuck,
What kind of wash and wax do you use on your engine? Mine just don't want to get or stay that clean!!
Nice pics .... Thanks for posting.
Yer welcome!  I have never, in the 4 years we've owned our coach, washed the engine.  It is always dusty (part of living in West TX), but it doesn't have any major oil leaks, so it stays pretty decent looking all by itself.  The old lift pump was leaking - that's why I replaced it.  In the photos, you can see the stains below the new pump from the prior fuel leakage.  Other than a couple other minor oil "seeps", our old engine is pretty "tight".

I guess we got a good one.  8)
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"

Re: 8.3 cummins filter confusion.

Reply #7 –
Thanks for all of the responses. Looks like pre-filling is in order.

 Chuck.
 What do you do with the slobber tube. Our engine stays pretty clean also.    But.  There is some soiling in the immediate area around  the end of the tube.  I've heard some put a bag on it or hang a can ?
Robert and Susan
 1995 36' 280 WTBI 8.3 3060r
 1200 watts on the roof, 720 Ah of lithium's
 Build # 4637. Motorcade # 17599
        FMCA  # 451505
        18  Wrangler JLUR
 

Re: 8.3 cummins filter confusion.

Reply #8 –
Quote from: Bob & Sue –
What do you do with the slobber tube.
I use the "hang a can" solution.  I have a bunch of empty aluminum tubular containers that originally held welding rod.  I cut a hole in a container lid that is a "loose" fit around the slobber tube, and hung the can on the end of the tube with some nylon ties.  It has worked fine for a couple years now.  I checked it once about a year ago, and there was a little oily residue in the bottom, but not much.  Unless your engine crankcase gets overfilled, I don't think there should ever be much more than a little vapor coming out of the tube.
1993 U280 SE 40' WTBI, Build: 4359
C8.3 300hp, 6-Speed, Exhaust Brake
960 watts on the roof (6 x 160)
Sorento (or BOLT) on a Kar Kaddy SS
"Nature abhors a vacuum"