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Topic: Fuel Pump Replacement and Dropping Fuel Tank (Read 1412 times) previous topic - next topic
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Re: Fuel Pump Replacement Decision
Reply #25 –
Working my way down to the generator.  Available time and assistance has me focused on the main tank connection for the genny.  Main engine fuel pump isn't exhibiting any symptoms of badness, which is why I was going for the slight drop instead of complete removal approach. If I take it all the way off, I may replace it pre-emptively; 80,000-ish miles.

Generator is 'surging' instead of running at steady RPM, which I understand points generally to fuel supply inconsistency (although other causes exist as well).  Since hose integrity is a known issue in the 2000 model year, and it's a (theoretical) $5 fix if handled at home, it seemed a good place to start.  I'm comfortable with the hard line between the hose bits on each end, since my 50+ year old sports car uses the same thing, and it's held up well. 

Generator-end hose segment is next of the low-hanging fruit, then genny fuel pump/carb attention is next on the list if still called for.  I'll be in that vicinity in a few weeks, attending to de-rusting and re-finishing propane tanks also.  I have a fuel pressure gauge that's good for EFI and standard carb pressures, so I'll probably verify pressure consistency as part of the troubleshooting.  I'm sorely tempted to add a 'tap' for quick fuel access, too.  On the fence about that one; there are some nice valves available for marine use, and a valve+cap affair should provide appropriate belt+suspenders backup.  Looking for safe, no-hassle transport of fuel for other types of equipment.

Chip
2000 Front Lounge
Re: Fuel Pump Replacement Decision
Reply #26 –
I replaced my Owan 4000 fuel pump in 2015.  Here is a link to the process.   When the fuel pump gets old it will some times deliver inconstant or weak fuel pressure.   At first the pump surged a few minutes and then would run just fine.  Then if I was using the AC in very hot weather it would sometimes cut out.  Finally I could not run the AC at all.  I went to a shop and had the generator and AC checked out (Restless Wheels RV in Manassas, VA.  No trouble found with either item, they were doing other work on the RV and did not charge me for those two items. I will go back to them in a hart beat if in need help).   Eventually the generator refused to start at all.  From the good folks here I learned how to check the codes on the panel (flashing light sequence).  Here is a link to the "how to" that is posted on the Lazy Daze Companion site. The Lazy Daze Companion: Generator - Replacing Onan 4000 Microquiet Fuel...
Currently: 2008 36' Tiffin Open Road
Previously: 2007 Mid Bath
Re: Fuel Pump Replacement Decision
Reply #27 –
John, thanks for the link and the comments.  I'll be adding them to the reading list.

Andl, just to complete the wholesale hijacking of Rich's thread (sorry)...
I snooped around with my little inspection camera tonight, and was able to read the words 'fuel' and 'vapor' on the genny line into the tank (position 3, hose clamps instead of fancy connector, line going to genny).  On an end view, it had the 6 or so fibers embedded in the sides that I've noticed on other aftermarket fuel hose. So my take was, the tank connection had been addressed before.  Line was soft and pliable, but not 'dead' gooey, and not dry and flakey.  I had the tank dropped on long bolts on left, and resting on a transmission jack on the right.  With tank 3/4 full, I was happy enough for now to re-secure it and troubleshoot the other end of the fuel line.  Re-securing the tank took all of 5 minutes.  Easy enough to pull when much emptier.

I peeled a little plastic wire loom away from the generator-end hose, and have found no writing so far, and the end view didn't show fibers in the walls of the tube.  I'll dig into that later next week.

I have three now-extra 12x1.75 mm threaded rods, about 6" long, if anyone needs them.  Of the 6 I made, I'll be keeping 3 for future use.

Chip
2000 Front Lounge
Re: Fuel Pump Replacement Decision
Reply #28 –
I'm still following along and enjoy reading the updates from everyone else.

I pulled into the driveway from my last weekend trip with the low fuel light on.  My plan is to try and drop the tank one of these weekends and see what's going on. 

The start of the trip was fine, no symptoms.  By the end of the trip I noticed a few extra cranks (3-4 seconds) before the engine fired up.  2 flips of the key (which starts the fuel pump for a few seconds but doesn't crank) seemed to help.  I'm taking that as a sign that I'm living on borrowed time. 

Rich
'03 MB in NC


2003 MB
Re: Fuel Pump Replacement Decision
Reply #29 –
I dropped the fuel tank today and ordered a new fuel pump.  Here are some things I learned for anyone thinking about doing the same.  My mid-bath LD is a mid-2003 chasis with a December 2003 delivery date.

You need a 15mm and a 21mm socket to drop the tank.  A 5/16" socket loosens the clamps connecting the fuel fill and vent just inside of the gas cap.  I hit the fuel tank fasteners (nuts on one side, bolts on the other) with some penetrating oil the night before and had no problems removing them.  I used 2 ratchet straps purchased in a 4-pack at Costco to control the descent (Goodyear brand, 1000lb limit, $20, Item#: 103929).  If you go this route, think ahead about how much strap needs to be rolled onto the ratchet to allow a complete descent.  You don't want the strap slipping when the tank is only halfway down.  I wrapped the hook ends of the straps around the frame. 

Combined with my HWH levelers, dropping the tank was easier than I anticipated.  Getting in back into place might be a different story.  I laid some 2x4's down to act as rails for sliding the tank towards the back on the rig once the tank was lowered and free. 

Getting to the fuel line disconnects was the trickiest for me.  You need a Ford fuel line disconnect tool to release the fuel lines, which is the same tool you use to change the fuel filter.  I always struggle with those disconnects.  Having done the fuel filters a few times (on various Fords) helped.  I wish the fuel lines were 6" longer. 

You will need pliers to remove the pinch clamps attached to the 2 fuel vent vapor valves.  The vapor vent hoses are showing some wear and I might replace them as well.  A 1/2" wrench will remove the nuts attaching the pump to the tank. 

Most of the tools are pretty standard, but I had to buy the 21mm socket and some people may not have the Ford fuel line tool.  I think most auto parts places carry them.

Fuel was almost empty (low fuel light was on) .  That made a big difference.  I plan to siphon out the remaining few gallons before reinstalling.  I would not attempt this with much fuel as pushing/sliding the tank around was useful. 

The infamous short piece of hose attached to the generator pickup was indeed cracked and aging.  Replacing it should make starting and running the generator easier.  That alone will make this project worth the effort. 

Amazon has the OEM part in stock (Motorcraft pfs20 for my 2003) and might be a good option for someone needing to find that part while traveling.  I ordered it tonight and it should arrive on Tuesday. 

For anyone following my entire saga, I have no doubt that the first mechanic I towed the RV to did not drop the tank, despite his statement to the contrary.  There was a collection of crushed acorns (mice) on top of the tank but no evidence of chewing on any of the wires or hoses.

Reattaching everything and lining the tank up for re-installation should be interesting.  It's always easier to take things apart than to put them back together. 

Suggestions welcome!

Rich
'03 MB in NC
 
 
2003 MB
Re: Fuel Pump Replacement Decision
Reply #30 –
Rich,
Sounds of success!
At least there is no broken 9000 lb. car lifts this time!
Rodney
1988 Mid Bath
Re: Fuel Pump Replacement Decision
Reply #31 –
Rich, take your other two ratchet straps and deploy them the same way, except hold off on threading/adjusting them until you need to relieve the first set as they reach over-extension or too-big-a-roll-o-strap on the reel.  In other words, have them at-the-ready to take over when the travel limits of the first ones are met.  That way, you don't have to block up the tank from beneath in order to complete your lift/lower process. 

To re-hang my tank, I had to use a ratchet to pull the tank to the right to align the holes.  Only needed to move it about 3/4", but it was steady and precise using the strap.  No prying needed (as there was nothing to pry on to move that particular direction...).

Are you considering extending all factory fuel lines enough to be able to drop the tank completely without worrying about disconnecting them? 

Chip
2000 Front Lounge
Re: Fuel Pump Replacement and Dropping Fuel Tank
Reply #32 –
If you own a rolling floor jack or a transmission jack, I would use it with along with the straps.
Place the jack under the tank, with a square of plywood between the tank and the jack.
The jack provides more stability and the ability to easily lift the tank.
I like the suggestion to use four straps, alternating them, if necessary, to provide the needed lift.

Instead of having 2"X4"s, on the ground to slide the tank on, use a couple of furniture dollies, if available.
They will make it easier to move the tank.

Do drain the tank as completely as possible, even a couple gallons of gas, sloshing around,  will make the tank cumbersome and unstable to handle. Our 2003 LD's gas tank has a drain in the bottom of the tank.

Please let us know if the Ford pump is the proper pump, once you have had a chance to compare them.
I need to do this before taking off on our summer trip.

Larry


Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze
Re: Fuel Pump Replacement and Dropping Fuel Tank
Reply #33 –
re: jacks -- I used a floor jack with a factory adjustable spreader bar for lowering,  Was able to adjust for slight fore-aft tilt, and put a pad on each end strap with a wood block in the center.  However, floor jacks describe a small arc when lifting and lowering, and some misalignment did occur. (On gravel, so no rolling to re-align.) Mid-stream, I switched to a scissor-style transmission jack, but used it to hold just the passenger side -- driver side was held by longer bolts, and I was only lifting one side. The V-groove in trans jack saddle was helpful.

Empty is better than full. Or even 3/4 full.  I'd like to know the thread size of the drain plug before I take it out.  Anyone know for sure -- 2000 E350 Super Duty (FL)?

Chip 
2000 Front Lounge
Re: Fuel Pump Replacement and Dropping Fuel Tank
Reply #34 –
I appreciate all of the suggestions.  I sometimes do things the hard and slow way (like siphoning the fuel instead of using the drain plug) just because I'm more confident that I won't screw it up.   In the end I siphoned 6+ gallons out and I'm sure I would have placed something like a 1.5 gallon container under the plug....

I'm also doing the job on a gravel parking pad which limits the usefulness of wheels at times. 

The Motorcraft pfs20 seems to be an identical replacement, down to some of the numbers stamped in the top plate.

I'm off to buy replacement hose for everything I can find before putting it all back together. 

Rich
2003 MB
Re: Fuel Pump Replacement and Dropping Fuel Tank
Reply #35 –
Rich,
I appriciate your work location.
Card board to cover the rocks.
Square wheels, wooden skids, and rachet straps.
Just like working in the dirt fields of my youth, 
Or the grassy suburban front lawnof today.
Rodney
1988 Mid Bath
Re: Fuel Pump Replacement and Dropping Fuel Tank
Reply #36 –
No shame in siphoning.  You have much more control.
Chip
2000 Front Lounge
Re: Fuel Pump Replacement and Dropping Fuel Tank
Reply #38 –
Quote from: rich  - 
I'm off to buy replacement hose for everything I can find before putting it all back together. 
Did you finish?
I'm planning on doing this soon, before it gets too hot.
The heavy rachet straps seem like a good way to do this.

Larry
Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze
Re: Fuel Pump Replacement and Dropping Fuel Tank
Reply #39 –
Not yet.  We took a non-RV trip over the weekend. 

Rich
'03 MB in NC
2003 MB
Re: Fuel Pump Replacement and Dropping Fuel Tank
Reply #40 –
I put the fuel tank back in place.  The coach starts beautifully and I can confirm that the pump listed upthead is working for me in a 2003. 

I'd say that reassembly was a bit easier than dropping the tank, but it took more patience.  In general, I would lift and tilt using a combination of the webbing straps and a floor jack until I could reach a connection (there are 5).  The generator hose was the easiest since there was lot of slack.  The rear tank fuel vapor vent was easy, and the forward vent was doable with the front of the tank lifted up and the rear slanted down.  I connected all 3 of these from behind.

To connect the 2 fuel lines I had to lift the rear and passenger sides of the tank up while leaving the front driver side down a bit.  From there I could reach up and from the driver side and reconnect the fuel hoses.  That is a one handed job (much easier than removal) due to the connection 'click' and the built in metal clips (as opposed to the plastic clips sometimes used). 

Reattaching the tank was a matter alignment.  The ratchet straps has a tendency to life the side with the ratchet more than the opposite side.  Also, I used a third strap attached to one of the rear skid guard to gently twist the tank into a straight line. 

There are 3 studs on one side of the tank (passenger) and 3 nuts welded to the frame of the driver side.  The studs were easiest to align and the bolts going into the nuts were a bit more difficult.  I did the studs first, but would probably try bolts first if I were to do it again.

In summary, it wasn't as bad as I thought it would be but it did take a bit of patience and thinking to get everything into the right place at the right time.  My fuel tank was empty, and I would not try it without an empty tank.  I also had a few floor jack and a few large blocks of wood to help direct/rest the tank as I wiggled it into place.

It might be placebo, but I was surprised as how quickly and easily the engine started for the first time.  To me it seems much improved over starting with the old pump.

I was also very pleased at how the generator ran with the hose directly in a fuel can (I haven't filled the tank to the generator dip level yet).  All of the surging and hesitating and hard starting was gone.  Again, maybe it's just my imagination but I think the cracked old piece of fuel hose was causing some issues.

Rich
'03 MB in NC
2003 MB
Re: Fuel Pump Replacement and Dropping Fuel Tank
Reply #41 –
Rich
Thanks for the great write up, I'm sure it will be of help to many, including myself.
Any idea how high the rear needs to be lifted, so the tank can be pulled out?

Larry

Larry
2003 23.5' Front Lounge, since new.  Previously 1983 22' Front Lounge.
Tow vehicles  2020 Jeep Wrangler Rubicon, 2001 Jeep Cherokee
Photo Collection: Lazy Daze
Re: Fuel Pump Replacement and Dropping Fuel Tank
Reply #42 –
Larry,
Based on my removal of the 36-42 gallon tank from an '88 MB, I would estimate, putting the rear wheels up 4 inches would give enough room to slide the tank out on cardboard.
Rodney
1988 Mid Bath
Re: Fuel Pump Replacement and Dropping Fuel Tank
Reply #43 –
I lifted with the HWH kickdown jacks, combined with 2 orange leveling blocks on each side.  I had more than enough room to slide the tank out.  Tires were still on the ground, but of course the suspension was sagging.  I also had a slight downhill slope behind the tires. 

I'm pretty sure the story from the first mechanic about not being able to slide the tank out was untrue.  From the bolts and dirt and other clues, he never dropped the tank as claimed. 

The bigger issue with height would be getting the fuel send and return lines disconnected.  I accessed them from the back (they are towards the front) and used as much height as I could get to reach both arms and the disconnect tool in there.  You might be able to get away with less height if you disconnect the fuel lines from the front driver side of the tank.

Sorry I can't be more help, but hopefully it will give you some ideas.

Rich
2003 MB
Re: Fuel Pump Replacement and Dropping Fuel Tank
Reply #44 –
Quote from: rodneyhelfrich  - 
Larry,
Based on my removal of the 36-42 gallon tank from an '88 MB, I would estimate, putting the rear wheels up 4 inches would give enough room to slide the tank out on cardboard.
Be aware that different models require different methods to change out the genset fuel hose. On our '02 30', the mechanic put the LD on an outdoors lift and simply lowered the rear tank supports (he may have loosened the front supports a little) and accessed the fuel hose from the rear. He made it look easy. It was actually a pretty quick job and around $200 I think.

Chris
Formerly: 2002 30' IB
 
Re: Fuel Pump Replacement and Dropping Fuel Tank
Reply #45 –
Quote from: Chris Horst  - 
Be aware that different models require different methods to change out the genset fuel hose. On our '02 30', the mechanic put the LD on an outdoors lift and simply lowered the rear tank supports (he may have loosened the front supports a little) and accessed the fuel hose from the rear. He made it look easy. It was actually a pretty quick job, especially on the lift, and around $200 I think.

Chris
Formerly: 2002 30' IB