Need Fuel System Help

Started by Xbird, June 12, 2019, 08:32 PM

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Xbird

Has been awhile since I've been on the boards, and the 'ol girl has had me hard at work since my last visit.
I just got back from a royally fun trip, think Gilligan's Island "three hour tour"  W%

Last couple weeks i went through the transmission soup to nuts and had a Hughes do me up a Towmaster HD torque convertor for the torqueflite. Along with that I re-did the fuel supply lines and filters and a few other TLC odds and ends on the chassis.

So with high hopes I set out for a 2 hour haul to the races that turned into seven fuel-drenched  $@!#@! words filled hours.
Looking for some advice/input as to what happened and here's what i've found so far.
As part of the "clean up" there was a rather greasy, ancient pump like device hanging in the air inline between the mechanical pump and the carb. I got rid of it, the lone wire terminal on whatever it was was long snipped off.

The main tank sending unit has a second hose on it that i would assume "should" be for a fuel return line from mechanical pump ??? That one has a bolt in the end stopping it up and sits at tank top level. I left that creation alone.
My fuel gauge doesn't work and I'm not too certain that the wiring on the main/aux toggle switch is correct. In "Aux" position there was 12v feeding the marine style switcher pump that the engine line goes into along with the main fuel feed lines from the two tanks. 

Before leaving, the main tank took fuel, then gave me overflow, so i figured she was full. The aux tank I had pulled the sending unit, soldered up the brass contactor, found rusty gas and decided to leave that alone and run only on the main.

About half way thru the trip, pulling a pretty monster hill she sputtered and died. found gas leaking from a split in what is either a breather or feed line that runs between the two tanks, 1/2 line.

After a lot of messing about, nearly killing the battery and having to prime the carb to fire, i got underway .... weakly enough to make the top of the hill, hit the exit and hit a gas station. Once again, fuel leakage when trying to gas the main tank, and she definitely could have taken some. crawl back under, and the breather (not the overflow line) was hanging down where it runs alongside the main fill hose. Stuffed that back up there, got it refired and that "seemed" to resolve things.
Two miles from the races and she dies again. I'm thinking Main is empty, so i go to add and am greeted with leaking fuel from that same breather. sure enough, another ruptured line, this time the breather right where it's connected.

Now I'm out of hose, line or anything to use to fix it, it's dark and it will not run off that main tank. i can prime the engine all i want, but can't get fuel in the tank, tank has fuel anyway and it won't run. Switching to the Aux side yields same no run condition. plenty of priming, but just will not take throttle just chokes sputters and dies.
so, laying under the mess, praying none of the good samaritan racers who keep stopping to help is gonna get out with a smoke in hand ... one did actually  ??? .... i finally stare at that switcher pump long enough to see that the new main tank filter is bone dry, the aux is full so the bulb goes off and i pull the engine feed and aux filter lines and plug them together to bypass that pump.
Bingo, fires gets me there and home trouble free.
Now for the fun. I've got the main tank down. drained and flushed. It has a dead float (no biggie, kinda nice to see i might get that working) It had 15 gallons of fuel in it. Aux has fuel in it.
What is stopping the flow?????
Would dead switcher pump do that? It clicked a couple times when i disconnected the wire, but did not run steady like a fuel pump. would that cause all the lines to over pressurize somehow?? just seems odd that line after line ruptured the way they did.

Is that capped fuel line from main's sending unit part of it ? should it be breather or a return? there is a newish fuel pump on the engine so no idea if it's is one that maybe didn't have a return line when the original did.
Any input welcomed.




ClydesdaleKevin

If I was you, I would try to restore the fuel system back to factory specs.  Put a new tank selector switch in...they still make them.  Put a new mechanical pump on, and install a new return line.  If you are using an electric low pressure pump, have it set up to push fuel to the mechanical pump.  Replace ALL your fuel lines, including the breather line giving you trouble, and maybe even the filler tube hose.  And replace every fuel filter.  The fact the you got it running and made it home tells me it probably isn't your carburetor of vacuum lines.  Also, check to see what kind of fuel cap you currently have installed!  I'm pretty sure those old Dodges require a VENTED fuel cap...someone may have installed a non-vented cap, which looks exactly the same...but will cause vapor lock.

Kev
Kev and Patti, the furry kids, our 1981 Ford F-100 Custom tow vehicle, and our 1995 Itasca Suncruiser Diesel Pusher.

Xbird

That's essentially the plan. Aside from the 1/2 inch breather/connector lines, i replaced everything else, and yes, the filler hoses are on the replacement list as are new sending unit filter socks and floats.
There were a lot of non-stock items added over the years, most of which were in non-functional status, that I have been eliminating. Got ride of a cruise control, clip on fuel line magnet, that old in line pump, assorted old muffler hangars, bodged 1-wire alternator, sun tachometer ... Also took off the spotlight, which IDK if it was a factory option or not, but was just too intrusive. I've also taken off the AC compressor which had a bearing on its way out and put in a 2-groove idler pulley in its place. At the same time, found that the power steering pump bracket had been bent around a bit, so that went in for a re-shaping that pulled 1/4" of angular misalignment back into place and provided much needed clearance between the mounting bolt head and alternator belts. Frame has been getting rustoleum hammertone paint job as I work my way around under there and she has a new set of shoes on her.

BamBam

Another thing to look at if you haven't replaced the fuel pump yet, is to check the length of your fuel pump push rod. If it's under 3.25" you'd better get a new one as that's a problem with fuel issues. Good Luck

Xbird

Got to thinking, this doesn't have a charcoal can in it any longer that i've noticed.  Hm? Not quite sure where the evap lines from those are/were actually routed with it MIA. may have been one tank to the other then just hanging in the air up top of the aux. tank. I haven't taken that one down yet.  I may have to j-yard up a can and put that back into the system. Also have to double check the mech. pump to see if it has a return line that maybe the previous owner capped off.

Xbird

Main tank is back in and all pretty, as is the chassis around it. Drained the Aux last night and just dropped it. Took out the filler neck, which went through the bench seat/water tank area and lo and behold, yellow crayon "77 Dodge Van" on it.
Pretty sure I have my hands on an owner-installed Aux tank setup which would explain the Sears toggle switch bracket, aftermarket selector pumps (the old dead inline one and the newer dead one) and soft copper fuel line runs. Since i haul around 5,000 lbs. plus, I'm thinking of saying "Adios" to the tank and all over it's rear axle overhang weight. Simplify and get rid of all the excess lines and wiring. My travels don't require the added fuel.

Fleetwood Jamboree owner's manual doesn't have any indication of provisions for an Aux. setup and doesn't show it as an optional system like it does with the generator.


ClydesdaleKevin

Quote from: Xbird on June 15, 2019, 03:05 PM
Main tank is back in and all pretty, as is the chassis around it. Drained the Aux last night and just dropped it. Took out the filler neck, which went through the bench seat/water tank area and lo and behold, yellow crayon "77 Dodge Van" on it.
Pretty sure I have my hands on an owner-installed Aux tank setup which would explain the Sears toggle switch bracket, aftermarket selector pumps (the old dead inline one and the newer dead one) and soft copper fuel line runs. Since i haul around 5,000 lbs. plus, I'm thinking of saying "Adios" to the tank and all over it's rear axle overhang weight. Simplify and get rid of all the excess lines and wiring. My travels don't require the added fuel.

Fleetwood Jamboree owner's manual doesn't have any indication of provisions for an Aux. setup and doesn't show it as an optional system like it does with the generator.



Sounds like you figured it out and have a plan!  Good job!  Just make sure your fuel cap is of the "vented" variety.

Kev
Kev and Patti, the furry kids, our 1981 Ford F-100 Custom tow vehicle, and our 1995 Itasca Suncruiser Diesel Pusher.

Xbird

 I decided to go with the simplification process and eliminated the rear tank. It's now running the main with a factory steel line from the tank to the engine fuel pump and no electric pusher. I kept one copper line from the aux. setup for the evap line off the top of the tank. It goes along the underside of the floor and goes up and over the water tank inline line (goes higher than the fuel filler level) and then back down through the floor so it acts like a plumbing trap to keep the fumes in when not running. trying to replicate the factory setup without the parts on hands at the present time was a no go.

Test drive found it to be a vast improvement performance-wise, I'm pretty sure the system has been sucking air since I bought it and had steadily gotten worse. Fuel gauge was also put back into service, figured out the original wiring run for it, spotted where it had been cut out of the harness and spliced to the switch, so that's all back to original with a male/female terminal pair on the leads at the harness connector.


   

Xbird

Just a little update. With the auxiliary tank gone and running 3/8ths line with an inline filter to the engine's mechanical fuel pump, the old girl made the last trip with no issues. Pulled 5,000 pounds up route 33, (starts out of home with lovely long climb) along 80 west with a 7 mile gradual uphill and did not peg the temp gauge. Runs so much stronger now. Got plenty warm, yes, but it didn't burn up the trans fluid or convertor and I only got into the 4-ways in the 40 mph range a couple times. The sending unit only reads up to a half a tank when full and hits E well before the tank is empty, i "cobbled" some carb floats onto the unit's rod since the brass float was too far gone to fix. i had to repair the contactor, so either that's hanging up on the wire coil or the floats I hung on it just don't have the volume. I'm quite surprised that based on fill ups I'm getting 7.5 mpg, thought it would be worse. Just finished prepping her for another trip to the same region, but family camping at Knoebel's, no trailer to haul til September

ClydesdaleKevin

Quote from: Xbird on July 28, 2019, 04:57 PM
Just a little update. With the auxiliary tank gone and running 3/8ths line with an inline filter to the engine's mechanical fuel pump, the old girl made the last trip with no issues. Pulled 5,000 pounds up route 33, (starts out of home with lovely long climb) along 80 west with a 7 mile gradual uphill and did not peg the temp gauge. Runs so much stronger now. Got plenty warm, yes, but it didn't burn up the trans fluid or convertor and I only got into the 4-ways in the 40 mph range a couple times. The sending unit only reads up to a half a tank when full and hits E well before the tank is empty, i "cobbled" some carb floats onto the unit's rod since the brass float was too far gone to fix. i had to repair the contactor, so either that's hanging up on the wire coil or the floats I hung on it just don't have the volume. I'm quite surprised that based on fill ups I'm getting 7.5 mpg, thought it would be worse. Just finished prepping her for another trip to the same region, but family camping at Knoebel's, no trailer to haul til September


Great to hear!  Good job!

Kev
Kev and Patti, the furry kids, our 1981 Ford F-100 Custom tow vehicle, and our 1995 Itasca Suncruiser Diesel Pusher.