Foretravel Owners' Forum

Foretravel Motorhome Forums => Foretravel Tech Talk => Topic started by: Jim Sizemore on March 23, 2016, 03:36:55 pm

Title: change fuel filter/water separator,leaking from drain.
Post by: Jim Sizemore on March 23, 2016, 03:36:55 pm
How stop fuel while filter unscrewed?

thnx,

Jim
Title: Re: change fuel filter/water separator,leaking from drain.
Post by: Chuck & Jeannie on March 23, 2016, 04:08:19 pm
Jim,

I'm not sure I'm understanding your question.  Are you asking if fuel will run out of the filter base while you are changing the filters?  In my limited experience, there is very little drainage from the lines while the filters are removed.  I was expecting it to be a problem the first time I changed mine, but it just didn't happen.  If anything, I think the fuel tends to siphon backwards toward the fuel tank, drawing some air into the lines.  That is why the engine runs a little rough when you first start it with fresh filters.

I warmed my engine up to operating temp before changing filters, and pre-filled my filters with fresh diesel prior to installing.  I had no difficulty restarting the engine after swapping both filters.

You do have a manual priming pump that is part of the transfer pump (lift pump).  See photo below of old and new pump.  The priming pump is the "button" on the bottom of the lift pump.  It is protected with a black rubber cover.  This primer can be used if you have a hard time getting the engine to start, but I did not find it necessary to use it on our coach. 
Title: Re: change fuel filter/water separator,leaking from drain.
Post by: Mike Leary (RIP) on March 23, 2016, 04:46:18 pm
The diesel engines have what's called a "high side" and a "low side". If you're changing filters, they're on the "low side" and need nothing to start. However, if you run the coach out of fuel (a no-no), you're on the "high side", and you'll need the pump to get it flushed of air. If that happens, be very carefull to shut the bleeder all the way down.  ^.^d
Title: Re: change fuel filter/water separator,leaking from drain.
Post by: wolfe10 on March 23, 2016, 05:01:34 pm
Mike,

Both your coach as well as the vast majority of Foretravels have two fuel filters:  Primary fuel filter/water separator between fuel tank and lift pump.  The secondary filter is on the pressure side of the lift pump.

Bleed procedure varies by engine family.  Some have an electric pump.  Some (like your Cat 3116) have a manual primer pump.  So no "one way fits all".
Title: Re: change fuel filter/water separator,leaking from drain.
Post by: Jim Sizemore on March 23, 2016, 05:10:44 pm
Mike,

  Some (like your Cat 3116) have a manual primer pump.  So no "one way fits all".

Thanks Bret - my manual says it is a 8.3 250hp Cummins. Where do I find a tag to verify same? It's an inline six.

Jim
Title: Re: change fuel filter/water separator,leaking from drain.
Post by: Chuck & Jeannie on March 23, 2016, 05:18:01 pm
Jim,

Brett's comment was directed at Mike Leary (who has a Cat), not at you.
Title: Re: change fuel filter/water separator,leaking from drain.
Post by: wolfe10 on March 23, 2016, 05:27:41 pm
Thanks Brett - my manual says it is a 8.3 250hp Cummins. Where do I find a tag to verify same? It's an inline six.

Jim


Yes, Jim, you have a Cummins "C"-- a very good engine.

 It is a linered engine, so be sure coolant is correct (either low silicate with added SCA that you check and keep the SCA concentration where it needs to be OR one of the newer long life coolants that do not require SCA testing and addition).
Title: Re: change fuel filter/water separator,leaking from drain.
Post by: Mike Leary (RIP) on March 23, 2016, 06:13:45 pm
Quote from: Chuck & Jeannie link=msg=227441 date=145 Brett's comment was directed at Mike Leary (who has a Cat), not at you. [/quote
Yup, and sorry for the confusion on my part: both my Isuzu engines had bleeders and I assumed (wrongly) all the big diesels had them, as well. Is it a pain to bleed the other engines if one (gasp) runs out of fuel?
Title: Re: change fuel filter/water separator,leaking from drain.
Post by: Chuck & Jeannie on March 23, 2016, 06:35:32 pm
Mike,

That's OK...confusion is normal around here.

Bleeding.  It has never come up for me (knock on wood), but on the (mechanical) Cummins engines I think all you do is loosen the fuel line connections on top of the injectors, and pump the priming pump.  When fuel dribbles out at the connection, tighten it back up and you're good to go.

I don't plan on EVER running out of fuel!  8)
Title: Re: change fuel filter/water separator,leaking from drain.
Post by: wolfe10 on March 23, 2016, 06:44:50 pm
Actually, "best practices" is to always run on the top half of the tank.  Fuel is used to lube and COOL fuel injection components and parts of the head on some engines.  For every gallon of fuel that goes to the engine, most return to the tank.

Operating on the top half insures better cooling of engine components/cooler fuel temperatures.
Title: Re: change fuel filter/water separator,leaking from drain.
Post by: Jim Sizemore on March 23, 2016, 06:49:45 pm
Thanks for the schooling session folks - and especially Bret as I was wondering about cylinder linings...

Jim
Title: Re: change fuel filter/water separator,leaking from drain.
Post by: J. D. Stevens on March 23, 2016, 09:13:07 pm
Bleeding.  It has never come up for me (knock on wood), but on the (mechanical) Cummins engines I think all you do is loosen the fuel line connections on top of the injectors, and pump the priming pump.  When fuel dribbles out at the connection, tighten it back up and you're good to go.
I suggest you NOT make any changes to the fuel lines on top of the injector pump. One of the mechanics at FOT loosened and tightened one of the injector lines to bleed air after they replaced fuel lines. I had a fuel leak at that point for a year. Folk at FOT could not find the source of the leak. I took the coach to someone who knows Cummins engines. He quickly identified the problem. He did some machining on the injector line and tightened it to the proper torque. It has not leaked since then.

I trust FOT to do a lot of service on my coach. However, I take the coach elsewhere if there is an engine issue that requires any more service than changing fluids.
Title: Re: change fuel filter/water separator,leaking from drain.
Post by: amos.harrison on March 23, 2016, 11:51:21 pm
I try to avoid changing filters with a full fuel tank, just in case.
Title: Re: change fuel filter/water separator,leaking from drain.
Post by: P. Wyatt Sabourin on March 24, 2016, 01:58:40 pm
With my 96 U320, to drain water from water/fuel separator, tank must be almost full or rear must be much lower than front. With less than 3/4 tank, air sucks into water/fuel separator, so there would be no fuel leaking when changing fuel filter. Air in fuel line is easily removed using suction on the schrader valve. I have a hose with female connector from a hand air pump that I use to do this.
Title: Re: change fuel filter/water separator,leaking from drain.
Post by: pocketchange on March 24, 2016, 02:26:17 pm
Amen for keeping your fuel level @ 1/2 tank plus.
Especially if you are the owner of anything with a small cell (ie; auto, pickup, etc..)
2 stroke additive and cetane booster hurt nothing.
FWIW.. Current fuel reg's and older diesels are not a positive combination.. pc
Title: Primary filter/water separator
Post by: Jim Sizemore on March 25, 2016, 12:09:13 pm
I'm having a heck of a time finding one - the AC number on Beamalarm will will not cross over to anything in my neck of the woods. The water drain valve on mine is leaking. Anyone have a good number of a filter that will replace mine? The one on there now has a transparent sediment bowl with the bleeder on the bottom of that - don't know if that was OEM or not....How do I keep from getting soaked when I take that filter off(as we did when we  replaced the fuel line!

Jim
Title: Re: Primary filter/water separator
Post by: nitehawk on March 25, 2016, 01:59:44 pm

For what it is worth--on my '89 DD 8.2--- I position a drain pan or pail under the primary filter. Then I test that I am going to be able to unscrew the filter. I do this, just in case I can't get it off easily. Then, having confirmed that I will be able to unscrew the filter I use a long bladed screwdriver and punch a hole in the bottom of the filter. I wait until fluid quits draining and then I unscrew the filter.
I prefill the new filter, grease the threads and the rubber seal, and then screw the filter on. I then start the engine and let it run for a few minutes to get any air out of the line.
I then proceed to do the secondary filter the same way.
Amazing how clean I stay compared to the old way of just unscrewing a full filter and getting diesel fuel all over everything!!
Title: Re: Primary filter/water separator
Post by: Jim Sizemore on March 25, 2016, 02:07:32 pm
What drenched us was fuel from the tank - running free flow until we raised the line 'til it stopped. Will fuel gush from the filter mtg as it does from the hose?

Jim

Title: Re: Primary filter/water separator
Post by: nitehawk on March 25, 2016, 02:10:58 pm
Most likely will keep running unless you put a clamp on the rubber line. Don't know if that would be a good idea, tho, unless lines are fairly new and pliable.
Title: Re: Primary filter/water separator
Post by: Bill Willett on March 25, 2016, 08:53:32 pm
I can be a Racor S3202 or a Fleetguard FS 19520, do yourself a favor and buy a second clear bowl, that way you can have a fitler that is prefilled and ready to swap out.
Title: Re: Primary filter/water separator
Post by: Rich Bowman on March 25, 2016, 09:05:39 pm
I try to make sure the tank is about 1/2 full and then raise the rear and lower the front of the coach.  Seems to help a lot.

Rich
Title: Re: Primary filter/water separator
Post by: FourTravelers on March 25, 2016, 10:08:41 pm
I installed a new Racor 1000FH turbine filter/water separator. IMO it would be less likely to plug up in the event of a bad tank of fuel.
Title: Re: change fuel filter/water separator,leaking from drain.
Post by: Jim Sizemore on March 26, 2016, 12:34:32 pm
I can be a Racor S3202 or a Fleetguard FS 19520, do yourself a favor and buy a second clear bowl, that way you can have a fitler that is prefilled and ready to swap out.
Bill, will you elaborate - I don't understand about the second bowl?
Do the sediment bowls come with the new filter? How about the petcock?

Jim
Title: Re: change fuel filter/water separator,leaking from drain.
Post by: wolfe10 on March 26, 2016, 12:44:26 pm
Jim,

Bowls do not generally come with the filters.  I agree-- easier and safer (in case a plastic bowl breaks) to have a spare bowl.  Install it on the new filter element at your leisure.  Makes changing filters less of a "drama".
Title: Re: change fuel filter/water separator,leaking from drain.
Post by: Green99 on March 26, 2016, 04:06:11 pm
Jim,
Fuel will continue to run out the hose when the filter is removed.  Try to find a large drain pan, and if you purchase another bowl you can assemble the new filter and have it filled with fuel so that when you drop the old filter you can immediately install the new, thus cutting down on the amount of lost fuel.
It is also good to have the second bowl so you can carry a spare filter already assembled in case you ever get bad fuel.