Emergency HELP Please F53 Fuel problems

[Gnarley]

WE are stranded in Grants Pass.

We broke down near the bottom of Sexton Pass on I5 on the Saturday of the Laborday Weekend. No Tow Trucks were available and we had to stay in the rig overnight 4 feet from the slow lane on a curve! We were towed at 11 AM Sunday morning back into Grants Pass and dropped at the Walmart and now safe. There are few tow rigs available in some areas and few shops or mobile techs or shops that can handle a large RV. This situation is exacerbated on long holiday weekends!

Vehicle: 1999 Holiday Rambler Vacationer F53 gas Triton v10, 1/3 tank of gas. Prior owner at some point installed a frame mounted aux fuel pump before and attached to the filter.

Conditions: Driving 55 MPH and pulling a dolly with a Hyundai Tucson on 9/5/2020 at about 2:30 PM and 99 degrees.

What happened? We don't yet know what failed. I crawled under and believed the aux pump failed and found a replacement. I installed it in the extreme heat, it did not fix the problem. It would start but did not continue running. FUEL or Pump in tank failure? We found a single mobile tech that was available, there were no other options. He showed up later Sunday and dropped the tank, the pump was non-op. We found one at a parts store and it was installed. It didn't seem to run any different. The tech questioned his install and dropped the tank again. Everything seemed as it should. Sunday he scanned and looked for codes and a few senors that were questionable were replaced as a precaution, and had no impact or change.

2 working pumps may have also overfuled the systems. We tried both and it runs really bad with the frame rail pump installed.

UNSURE what to think. Tuesday morning after checking various connections and replacing a suspect damaged fuel pressure regulator we removed the frame rail secondary pump!

We drove with the engine cover off and had a fuel pressure gauge hooked up to the fuel rail and it had the correct pressures and the engine ran perfect! Up and down hills in town for about 30 minutes and no problems! You could watch the fuel pressure rise on the hills as should be expected. We put the engine cover on and went for a drive on I5. It immediately had a problem and under load lost pressure.

Everything was good with the engine cover off and with it on there was more heat and had an instant effect on drivability. SIDENOTE we only had about 1/3rd tank of gas, could a pump that's not fully submerged overheat and cause a loss of fuel pressure under load?

Due to the fires we are stuck. The 2 week trip we planned is canceled and now we are trying to get back home. We may have to abandon our RV and store it since we don't trust driving it home 400 miles away.

Does anyone have any helpful suggestions?

Please help

Thanks

[GypsyR]

I'd be looking at "voltage drop" issues. Google and YouTube explain it and how to test.
My coach is older but I had issues too and went to look at the fuel pump relay. It was fine but I happened to turn it over a bit and caught a glimpse of a bit of green inside the back of the plug. I immediately started poking and prodding and found the main power supply wire to be so green and corroded at the end I pulled it apart with my fingers. In that instance I just chopped all the wires off back where they seemed clean and healthy and then wired up a brand new plug and relay.

I had the tools ready to do voltage drop testing at that point it just happened I lucked out with a bit of visual inspection first. No idea why is was corroded. It's positioned up high behind the engine firewall and even had an extra protective plastic cover over it all.

Best of luck to you.

[arcaguy]

Have you changed the fuel filter? That would be my first guess if it seems like a fuel starvation issue.

[Argosy]

What's your coolant temperature with the engine cover off and on? Is the engine fan operating?

[Solo_RV_Guy]

Originally Posted by Gnarley

WE are stranded in Grants Pass.

We broke down near the bottom of Sexton Pass on I5 on the Saturday of the Laborday Weekend. No Tow Trucks were available and we had to stay in the rig overnight 4 feet from the slow lane on a curve! We were towed at 11 AM Sunday morning back into Grants Pass and dropped at the Walmart and now safe. There are few tow rigs available in some areas and few shops or mobile techs or shops that can handle a large RV. This situation is exacerbated on long holiday weekends!

Vehicle: 1999 Holiday Rambler Vacationer F53 gas Triton v10, 1/3 tank of gas. Prior owner at some point installed a frame mounted aux fuel pump before and attached to the filter.

Conditions: Driving 55 MPH and pulling a dolly with a Hyundai Tucson on 9/5/2020 at about 2:30 PM and 99 degrees.

What happened? We don't yet know what failed. I crawled under and believed the aux pump failed and found a replacement. I installed it in the extreme heat, it did not fix the problem. It would start but did not continue running. FUEL or Pump in tank failure? We found a single mobile tech that was available, there were no other options. He showed up later Sunday and dropped the tank, the pump was non-op. We found one at a parts store and it was installed. It didn't seem to run any different. The tech questioned his install and dropped the tank again. Everything seemed as it should. Sunday he scanned and looked for codes and a few senors that were questionable were replaced as a precaution, and had no impact or change.

2 working pumps may have also overfuled the systems. We tried both and it runs really bad with the frame rail pump installed.

UNSURE what to think. Tuesday morning after checking various connections and replacing a suspect damaged fuel pressure regulator we removed the frame rail secondary pump!

We drove with the engine cover off and had a fuel pressure gauge hooked up to the fuel rail and it had the correct pressures and the engine ran perfect! Up and down hills in town for about 30 minutes and no problems! You could watch the fuel pressure rise on the hills as should be expected. We put the engine cover on and went for a drive on I5. It immediately had a problem and under load lost pressure.

Everything was good with the engine cover off and with it on there was more heat and had an instant effect on drivability. SIDENOTE we only had about 1/3rd tank of gas, could a pump that's not fully submerged overheat and cause a loss of fuel pressure under load?

Due to the fires we are stuck. The 2 week trip we planned is canceled and now we are trying to get back home. We may have to abandon our RV and store it since we don't trust driving it home 400 miles away.

Does anyone have any helpful suggestions?

Please help

Thanks

The problem is heat, but why is the failure nearly instantaneous upon replacing the doghouse? {scratching chin}

Something is spewing more heat than it should or something has changed (loss of a heat shield, maybe?) that keeps heat from building up. It's how quickly it happens that is stumping me because it would otherwise be a classic symptom of vapor lock.

[Gnarley]

I just wanted to post an update.

We didn't have much time to do anything after 4 nights and there were no open RV sites we could access. There were no options for fixing it today and no options to get it home. I was able to find a caring older man who has a small storage yard and went to personally meet and ask if he'd allow me to store my rig and he trusted me and we signed an agreement and paid him 2 months upfront. We found a U-haul truck that that could tow our dolly and car and set the plan in motion.

We got back to the rig and spent 3 hours transferring everything we had in it to the U-haul in the event break in or theft. We finished and I was able to drive it to the storage and park it.

We hit the road about 5 and drove through to Redding, CA for the night. The rig is safe and we have all of our personnel belongings and will be home early afternoon.

Once I get unpacked I'll be checking everyone's ideas and suggestions for finding the problem and getting it fixed.

On the way south we drove through active fire areas in Southern Oregon and witnessed 3 large jumbo jets dropping retardants and many other helicopters in terribly devastated burn areas, it was heart breaking.

Hugs to everyone and love to close to you,you never know when something like this may happen to you.

Thanks everyone for your support and suggestions.

[edge68474]

I am sorry for your problem and hope you can get it fixed soon.
Please let us know when your rig is fixed and running correctly and the solution. Their are many of us with the same chassis.
Thank you and Good Luck.

[NXR]

A question to me is why the previous owner installed the second fuel pump.

Was it because he knew the one inside the tank had failed and he did not want to pay for a proper repair?

Or was it because there is a heat problem causing the fuel in the lines to vaporize so he added a second pump to overcome that. I know some people do that when they have a problem with a gasoline generator getting vaporized fuel.

I'd trace the fuel line from the tank into the engine to see if anything looks odd. The line too close to the exhaust, a fuel line that looks non-factory, etc.

I believe there is a wrap-on insulation for fuel lines so maybe you can take some with you just in case you find a section of the fuel line that may be exposed to high temps.

Ray

[PbdBlue]

It's pretty rare to have a vapor lock issue with properly operating FI system. It was more of an issue back in the carb days when the fuel line pressure was much lower. You should not need a secondary pump and it probably will cause more problems than it solves. If you haven't already I would recommend removing it.

[Gnarley]

Originally Posted by edge68474

I am sorry for your problem and hope you can get it fixed soon.
Please let us know when your rig is fixed and running correctly and the solution. Their are many of us with the same chassis.
Thank you and Good Luck.

I absolutely will share! I see you have a HR, do you have any HR resources?

[Gnarley]

Originally Posted by NXR

A question to me is why the previous owner installed the second fuel pump.

Was it because he knew the one inside the tank had failed and he did not want to pay for a proper repair?

Or was it because there is a heat problem causing the fuel in the lines to vaporize so he added a second pump to overcome that. I know some people do that when they have a problem with a gasoline generator getting vaporized fuel.

I'd trace the fuel line from the tank into the engine to see if anything looks odd. The line too close to the exhaust, a fuel line that looks non-factory, etc.

I believe there is a wrap-on insulation for fuel lines so maybe you can take some with you just in case you find a section of the fuel line that may be exposed to high temps.

Ray

Something happened to need the frame-mounted pump and it had to be installed for the previous owner, but we don't know exactly why. When we dropped the tank on Sunday we found an aftermarket carter pump, no sock-strainer, the pump was not secured to the assembly, and hanging by the line that connects it to the output line of the assembly, it was a shoddy job! It seems that the tank pump failed, this is also called a lift pump I believe. The new frame pump I installed could not pull fuel past the lift pump. Once a new tank pump was installed and there were 2 working pumps we think that it had too much pressure and low-end drivability was terrible! We removed the secondary pump and the AM test drive on Tuesday confirmed that it could run correctly, it ran perfectly! After adding the dog house in the high heat the problem showed that pressure dropped under load, the harder on the gas or greater the hill the faster the pressure dropped.

Regarding the generator it has a separate line that does not go to the bottom of the tank like the pump does that sits about 1/4 inch off of the bottom. THe generator line only goes down 3/4 of the way and then will stop drawing fuel

[Gary RVRoamer]

It seems evident to me that the frame-mounted pump was in lieu of the non-working tank pump. Now that you've fixed that, eliminate the second pump and move on to the next problem.



Definitely find and replace the inline fuel filter, just to be sure. A dirty filter can cause all sorts of weird symptoms, so eliminate it as a possible issue.


The doghouse variable would seem to suggest a heat problem, but that has to be rare in a direct-injected fuel system like yours. Maybe it's not the old vapor-lock at all. Instead it could be excessive heat in the air intake or an ignition wire failing or maybe even the engine cooling system. When you are focused on a fuel problem, you may have missed some other possibilities.


I recall an engine problem with a Workhorse chassis in National RV coaches that was the result of chassis/body air baffles deteriorating after several years. Cooling air that was supposed to be traveling up and over the engine instead escaped out the wheel wells and some owners experienced performance problems. I'll not go into details because yours is a Ford, but wanted to make the point that air flow over and around the engine can be critical.

[NXR]

Do you have a ScanGuage II or similar, a device that plugs into the OBD II diagnostic port and continuously reads a number of parameters?

Before you just buy one at an auto parts store, I'd confirm that a chassis that old even has an OBD II port. I know the 1997's did not but I do not know when they were added to the F53. This post may help you determine if you have the port: https://www.irv2.com/forums/f23/1998...rt-491538.html

You may be getting tunnel vision because of the fuel pump problem. The lowering of the fuel pressure may be a symptom of something else and an OBD II device may help you determine that.

Ray

[SKP Kirk]

Because of the doghouse issue, I would take a hard look at the fuel lines in the engine area. There has to be some reason the previous guy had two fuel pumps. I would also want a look at the scan codes. I had that same chassis for 14 years and there is an OBD II port. Ford started to install them in 1997.