Community Forums

6wheeler · 06-01-2023, 06:58 AM

Hi all. So, I have a problem with the coachman. Since I bought it, the fuel guage hasn't worked. I just stop and fill it every 150 miles or so. On our last trip over the Memorial Day weekend. It ran fine and idled fine. But? Then it started dying out under power. As long as I didn't put my foot into it, it did fine. Being an old Ford guy. I know the issue is going to be fuel related. Specifically, the filter is most likely the problem. It is a 1988 Ford E-350 chassis with the 7.5l (460) in it. This is one of the the first major forays into fuel injection that Ford did. So, It has The low pressure pump in the tank feeding into a reservoir then into the high pressure pump, to the filter then to the injectors. Since I am changing the filter? I was thinking of replacing the rear fuel pump, because the gauge doesn't work. I had to figure out what size tank it has. I have all the books and paperwork that came with the coach. Because I bought it from the original owner. But, nothing in the paperwork tells me what size tank it has. I crawled underneath and could read the numbers on the fuel tank. The numbers are E8 US 9002 AB. I can't find that number on Fords sight. But? I believe it is a 37 gallon tank. Because, the first 4 digits don't match any tanks but the last 6 do. As a 37 gallon tank, It takes a different fuel pump than what I have seen. It is going to need to have 3 outlets in it. 1 for the outlet. 1 for the return. And? 1 for the generator. Has anyone found one of these? Or do you know if I can have it rebuilt somewhere? The pump works. But, the sender does not

MrMark52 · 06-01-2023, 07:07 PM

What you don’t know is if the coach builder installed a different tank in the chassis, especially since the numbers you found don’t look like Ford #’s.

Since your thinking about dropping the tank anyway - just go ahead and do it - pull the assembly, and take it to the auto parts store. I did that for our previous ‘91 coach in ‘18 although the actual pump was all that needed replacing. And fortunately, the assembly wasn’t all rusted out like I’ve seen with other older vehicles not designed to handle “up to 10% ethanol” gas.

Sending units are easy to repair anyway once you get the assembly out, assuming it isn’t corroded away.

RickNC · 06-02-2023, 03:41 PM

I had a similar issue when I replaced my in tank pump. I measured height x width x length and divided the result by 231( Cubic inch volume of a gallon ) it should get you with in striking distance of your tank size choices.

MrMark52 · 06-03-2023, 08:01 AM

Good advice from RickNC!

And I will better qualify my experiences and justification for dropping the tank anyway - while our ‘91 coach on a Chevy P30 chassis didn’t have a rusted up pump/sending unit assembly - recently working on a friends 84 Jeep CJ, and about 10 years ago working on another friends 70’s model Datsun 280Z, both vehicles the gas tanks were horribly cruded up and rusted. None of which was detectable when looking down the filler hose or evidenced by clogged filters.

Mizzbos · 06-25-2023, 03:47 AM

Thank you for all of this information. I have a 2000 coachman mirada that idles fine, however when in tow. I lose Rpms. Was totally banging my head trying to figure out what direction I need to go. Will be dropping my tank with in a couple of weekends.

GypsyR · 06-25-2023, 07:23 PM

First thing you might want to do is check the fuel pressure and confirm it's a fuel problem.
I had rather the same thing. To start with it was weak pump. Then it was old fuel debris in the tank choking up the rather puny stock "sock" filters on the pump. Both had almost the same lack of power symptoms but with the clogging filters I could stop and rest a while and the crud would settle out of the filters enough for me to limp it a ways further back home. (A nerve-wracking little trip.)