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Topic: Primary Fuel Filter upgrade options for Cummins ISC (Read 3081 times) previous topic - next topic

Re: Primary Fuel Filter upgrade options for Cummins ISC

Reply #25 –
A very interesting discussion and I'm certainly getting an education.  I'm looking at the fuel system from 40 years of boating and maintenance in harsher environments and wondering if this is not getting a little over thought. The specs on filters obviously is based on different criteria.  The engine needs 6 to 10 gal. an hour to burn and the balance of that is for cooling and is returned to the fuel tank. The major pollutant problems could be eliminated by polishing, considerably cheaper than the high tech expensive filtering methods mentioned. A filter/water separator built from a pump and filter from a fuel tank transfer pump like used by construction and agriculture purposes is functional and cheap. A Racor filter system with valves and parallel filters eliminates changing filters on the road and a vacuum gauge down stream will tell you what's going on. And all of that is low tech, cheap, and easy to install and maintain. High tech isn't always better, but it is a challenging hobby.

wantabe

Re: Primary Fuel Filter upgrade options for Cummins ISC

Reply #26 –
It as the very rear of the coach directly behind the engine access doors. It is mounted where it is higher than the top of the fuel tank. With a new filter element installed, the fuel level in the bowl is only a couple inches up on the filter. Over time it slowly climbs but I have never seen it over about 1/2 to 3/4 up the filter.
Previous coach - 2007 Phenix 45'

Re: Primary Fuel Filter upgrade options for Cummins ISC

Reply #27 –
The engine may be burning 6 to 10 gallons an hour, but the cooling aspect is very important. The ECM, the CAPS pump (in the Cummins ISC), etc. are all cooled by the fuel. In looking at the Cummins Insite software while diagnosing the stop engine light problem, the fuel temperature was right at the top limit and was undoubtedly caused by the restriction. i.e., The CAPS pump is starving for fuel resulting in the over pumping fault code, and there is less fuel being returned to the tank for cooling. Also, I disagree that this is a high tech approach merely a change in the primary fuel water separator and choosing the best mounting location to make it easier to service and the visual check to tell when just makes sense to me. Setting up a fuel polishing set up is definitely on my radar and I may do that at some point, but certainly not cheaper than than my $160 eBay new old stock filter. Nor would mounting a multi-parallel set up with valves in the limited space be a trivial pursuit... but each of us comes to the solutions for the issues that crop up by the means which our own experience and thinking process prepares for us. Yours may well be different. Those who haven't been bitten by the cr@p fuel issue and had to change filters by the roadside (assuming they know what caused the problem in the first place), won't like see the point of all this discussion and are free to ignore it under the principle of "Do What Makes You Happy" frequently mentioned on this forum (Thanks Dave M!).
Don
Quote from: wantabe –
A very interesting discussion and I'm certainly getting an education.  I'm looking at the fuel system from 40 years of boating and maintenance in harsher environments and wondering if this is not getting a little over thought. The specs on filters obviously is based on different criteria.  The engine needs 6 to 10 gal. an hour to burn and the balance of that is for cooling and is returned to the fuel tank. The major pollutant problems could be eliminated by polishing, considerably cheaper than the high tech expensive filtering methods mentioned. A filter/water separator built from a pump and filter from a fuel tank transfer pump like used by construction and agriculture purposes is functional and cheap. A Racor filter system with valves and parallel filters eliminates changing filters on the road and a vacuum gauge down stream will tell you what's going on. And all of that is low tech, cheap, and easy to install and maintain. High tech isn't always better, but it is a challenging hobby.

wantabe
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Don & Tys
1999 U270 3602 WTFE #5402
Xtreme Stage 1 w/Headlight, Step Conversion, etc.
2009 Honda Fit Sport with Navi
Freedom is NOT "just another word for nothing left to lose"... with apologies to Kris Kristofferson

Re: Primary Fuel Filter upgrade options for Cummins ISC

Reply #28 –
I totally agree....just wanted to offer another solution. Also, a fuel cooler might  be considered.

Wantabe

Re: Primary Fuel Filter upgrade options for Cummins ISC

Reply #29 –
I don't know about previous years, but the 99' U270 has a fuel cooler in front of the radiator. I imagine with advent of electronic engines and the use of fuel for cooling the electronic components, Cummins required the OEM's to include them.
Don
Quote from: wantabe –
I totally agree....just wanted to offer another solution. Also, a fuel cooler might  be considered.

Wantabe
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Don & Tys
1999 U270 3602 WTFE #5402
Xtreme Stage 1 w/Headlight, Step Conversion, etc.
2009 Honda Fit Sport with Navi
Freedom is NOT "just another word for nothing left to lose"... with apologies to Kris Kristofferson

Re: Primary Fuel Filter upgrade options for Cummins ISC

Reply #30 –
On my Newell the Davco filter was mounted at about where the center of the tank would be.  One has to remember that you need room at the top in order to fill the filter with fuel after you change the filter.  It takes about 3 quarts or so.  Therefore on the Newell in stead of hauling diesel in a can in case one got bad fuel and had to change the filter on the side of the road,  we carried several bottles  of Dextron ATF to fill the filter. Lot easier than diesel.  I was lucky and never had to use AFT but there were members of the forum that did. The old Detroit loved it as much as diesel.
 I change the filter about every 18 months.
Chappell & Mary
36' 2004 Foretravel U270 build #6273

Re: Primary Fuel Filter upgrade options for Cummins ISC

Reply #31 –
I am updating this thread as I have gotten a chance to work on the coach in the ultimate man cavern (much to big to be a man cave!). We are enjoying the Texas hospitality of Bill Chaplin in his amazing warehouse/shop South of Ft. Worth. We had a few more issues with the fuel filter on the way here, and so while I am hoping to take advantage of this opportunity to work on the coach indoors and get a few more projects done while at the warehouse, the fuel filter has jumped the priority list and everything else will take a back seat. I have refined the the mounting location and made a mounting plate out of ¼" steel that is bolted to the heavy duty rectangular tubing that borders the engine compartment. This places the elevation filter element at or very near to the full tank level. I will also put in a shut off valve on the supply side of the filter to keep the prime if I remove the filter base to access other components for servicing. There is a check valve on the input side of the filter that will do that if you are just changing the filter element. I will have a couple of braided stainless steel teflon lined hoses made to order, so I wanted to finalize the mounting location to be sure of the length and choice of fittings. These hoses won't be cheap, but they will be flexible enough to route optimally and total extra length will be less than six feet. Here are a couple of pictures of the filter location, and a few of the Warehouse environment. I do love rustic campsites surrounded by trees and all that, but an indoor facility to get projects done with a 50 amp electrical hook up is 5 stars in my book! :D
Don
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Don & Tys
1999 U270 3602 WTFE #5402
Xtreme Stage 1 w/Headlight, Step Conversion, etc.
2009 Honda Fit Sport with Navi
Freedom is NOT "just another word for nothing left to lose"... with apologies to Kris Kristofferson

Re: Primary Fuel Filter upgrade options for Cummins ISC

Reply #32 –
Wow- that looks great Don.  I am very interested in this too as I had some misses and check engine light again, that is after changing filters twice.  If this works for you I might have to consider that upgrade.

On my coach that looks to be in front of the D2 and the PureAir Halex air dryer.  Wondering if they will still be accessible with the new fuel filter there?   
Ted & Karen
2001 U270 36' - sold after 12 years full timing

Re: Primary Fuel Filter upgrade options for Cummins ISC

Reply #33 –
That does make the D2 governor less accessible, though still doable with out removing the filter canister via reach around (at least for me 8) ), but the Air Dryer wasn't particularly accessible before I put the Davco 382 there. Any work on the Air Dryer really means accessing from behind and underneath (which would be necessary to remove the air lines anyway). The last picture shows the Air Dryer mount from behind. You can access the air dryer mounting fasteners from directly behind even with the Davco in place. That said, my experience thus far says that I am much more likely to need to get to the fuel filter than either the governor or the dryer. At this point, I just need to take the bikes off the rack to open the hatch to change the filter, or with the bikes on, just open it a crack to examine the restriction level... I may be able to see that through the grill, but I haven't closed the hatch yet so we will see.
I had one braided stainless line made up from a hydraulics shop in Cleburne, TX. It has a crimped on 90º sweep on one end and a straight fitting crimped on the other end. The crimped fittings are JIC (37º taper) and they are connected to the filter with ½" MPT to JIC adapters. The new line is called ½", but the crimped on fittings have openings that are only hair over 5/16". This is just a bit smaller than the openings of the ⅝" OD Parker fuel lines with the DOT air brake compression fittings that Foretravel put in about 4 years ago. The next size up that hydraulic shop stocked is ¾" and this was much stiffer and appeared to be almost twice the diameter of the ½". Time will tell if I will need to upsize the line. I finished the install of the Davco today and tested it, though just at idle. It was very easy to pre-fill the filter unit and purge the air. I used the key-on 45 second running of the lift pump after pre-filling the filter unit about three times and then started it while Bill Chaplin looked on. A lot of air bubbles at first, but it didn't stall. I topped of the filter housing and started it again and within 30 seconds or so, no air bubbles and the level visible in the filter settled down to its initial level visible in the picture. I am going to change the height control valves now and when I am done with that, I will take it for a road test... One good thing about the Davco system is that pre-filling the filter unit puts adds the the diesel on the unfiltered side of the element so that what ever you add from the can gets filtered before it gets to the secondary filter. I will continue to update this thread as I see the results over time.

Quote
Ted & Karen
On my coach that looks to be in front of the D2 and the PureAir Halex air dryer.  Wondering if they will still be accessible with the new fuel filter there?   
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Don & Tys
1999 U270 3602 WTFE #5402
Xtreme Stage 1 w/Headlight, Step Conversion, etc.
2009 Honda Fit Sport with Navi
Freedom is NOT "just another word for nothing left to lose"... with apologies to Kris Kristofferson
 

Re: Primary Fuel Filter upgrade options for Cummins ISC

Reply #34 –
Some notes on the parts and process of relocating the primary fuel filter from behind the curbside rear dually's above the chassis batteries to the area accessible by opening the engine bay door. On our coach, a 99' U270 with the CAPS fuel system electronic ISC 350HP, the original Racor filter housing was located above the chassis batteries at arm's length through the hatch behind the passenger's side rear wheels. This location is not very convenient for servicing, but makes sense from a plumbing point of view as it places the primary filter in line and close to the lift pump. The right side of the Racor housing is the inlet side with the filtered fuel exiting on the left side. Placing the Davco unit where it would be at the recommended mounting height and accessible without standing on my head or opening up the bed to access from above required me to extend the fuel line 6' coming from the fuel tank. I went with a teflon lined braided stainless steel hose with crimped on ends which my research indicated is suitable for pretty much any kind of chemical including diesel fuel of all kinds.
I had Foretravel replace the fuel lines (all of them) just under four years ago, and they used what they are using on their new coaches. It is a Parker HTFL (High Temperature Fuel Line), ⅝" OD for the main engine and ⅜" OD for the generator. The Parker fuel line has a consistency like air line used for brakes, but is a different color. In fact, he fittings used for the main fuel line are DOT brake line fittings. The ones used by Foretravel for the fuel lines are the compression type rather than the PTC (push to connect) type. The sizes apparently are not that common on air brake systems as the truck parts place didn't have many options and the parts counter guy seemed surprised to find some for the ⅝" OD tubing. The fittings on the Racor I/O are ⅜" FPT (female pipe thread), and the Davco has ½" FPT I/O. The Dot fittings can ban be adapted on the pipe thread side, or you can get fittings that have the ⅝" OD compression (or PTC) on one side and ½" male pipe threads on the other. The 6' extension I had made at the hydraulic's shop have JIC fittings only so I got the JIC male to ½" FPT adapter extend the fuel line from the tank. At the filter housing which has a JIC female swivel and an adapter that goers from JIC male to ½" MPT the is screwed into the check valve fitting. A note on the JIC fittings: These fittings utilize a 37º taper and do not use any kind of sealant on the sealing surfaces. On the pipe thread fittings, I used Loctite 567 which is the same as what I use on pipe threads in the air system. I also installed a ball valve between the Foretravel installed fuel line and the extension. This is a ½" brass valve that is rated for WOG (water, Oil, & Gas). By slightly rerouting the main fuel line from where it had been connected to the Racor unit where it had to make a 90º turn towards the curbside, I was able to feed it so that it ended right inside the engine compartment on the corner so that the shut off valve is reachable by opening the bed.
Don
Quote from: wolfe10 –
Let us know where/how high you install it and what extra hoses it took (if any).
Thanks.
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Don & Tys
1999 U270 3602 WTFE #5402
Xtreme Stage 1 w/Headlight, Step Conversion, etc.
2009 Honda Fit Sport with Navi
Freedom is NOT "just another word for nothing left to lose"... with apologies to Kris Kristofferson