Fuel problems persist

[Mat7783]

So I posted about my fuel filter change outs and now my prime pump is leaking so I have one on order.here is my problem: when I hit the ignition, I hear a pump clicking. Is this the fuel transfer pump? I read that the water seperator gets fuel thru vacuum in the lines. Am I understanding that correctly because I removed the filter again and it is empty after i initially filled it at install.this filter should always be full and daring any water from bottom as necessary. Am I missing something here???

[Native]

It would seem you are not getting fuel from the tank to the prime pump.


Have you drained some of the fuel from the tank to see how it looks? The filters really look nasty and if they have rusted, then there was water in the fuel. Water in the fuel usually come from the tank.

[Mat7783]

Yes I drained 25 gallons of fuel from tank. Put 18 gallons of fresh fuel in and star tron fuel treatment. Once I figure out what the heck is going on with this crap, I can take for a spin and start burning some fuel.

[Brad_SwiftFur]

It's possible the two fuels are "summer blend" and "winter blend" (they will appear different), when was the 2 fuels purchased? Even in Florida, during winter months most fuels will be winter blended, mostly for truckers who may end up in very cold northern states before fueling again.

[mmoore6856]

take a shop rag and a blow gun to the tank fill port and add some pressure to the tank while having somebody pump the primer. when it gets hard to pump close and lock the primer pump [or it will suck air]. keep the shop rag and air on the tank and try starting it

[mmoore6856]

fuel color is not your issue dont get distracted

[mmoore6856]

my fe does not use a lift [electric ] pump. race your fuel lines and see if you have one. if so disconnect the feed hose at the primary and see if your lift pump is plugged

[BamaBus]

Originally Posted by mmoore6856

fuel color is not your issue dont get distracted

I agree its not the main issue. It seems you had a problem from the start and got some good advise in your "Fuel filters changeout issue" thread. If the junk on top of the fuel separator is any indication of what was in your tank, it a good bet that more of that has clogged or partially clogged the fuel line or fuel pick-up. If the primer pump is leaking it could also be causing a vacuum leak. Just my thoughts. Sorry you are having this issue.

[Mat7783]

Thanks guys for the valued input. I drained 25 gallons since I the bus was losing power several times driving it home. Furst time driving a bus 125 miles and pulling onto highway shoulder 4 times was very stressful but I made. My old nasty water seperator was bone dry which prompted me to change filters immediately and drain some fuel just because of the unknown.so I am changing out the prime pump handle and will see what happens.the empty seperator is very concerning.

[mmoore6856]

make sure the primer is closed and locked before starting as they will suck air if not

[Mat7783]

Well I have an update on my fuel saga.so when I changed out those nasty filters after limping home,I did not realize that the separator filter mount was changed and not CAT version, so the OEM CAT filter I put in was smaller than the Purolator version and air was Shaping out from seal. Got bus started after putting in proper filter but now for the real issue. No fuel was getting to separator filter from tank until we forced compressed air in the tank as mentioned on your awesome responses and input, because I have RUST IN THE TANK and clogging fuel port.that may explain the nasty orange looking fuel While draining some fuel. Now I have to drop this 100 gallon tank and see if it is salvageable.my ride home initially as described previously was due to rust clogging port during highway travel. The bus got going after letting this crap settle for 10 minutes To the bottom of the tank and the issue repeats itself. I am SO NOT LOOKING FORWARD
TO THIS TASK! Wanted to share my findings with you all in case this topic resurfaces.

[Booyah45828]

So, you were sucking air past the separator and that's why it would run and then die.

The rust in the tank explains the orange crap all over the filters, the orange colored fuel, and why the filters plugged in the first place.

Tanks can be dropped and cleaned, but if it's that bad, you might want to look into getting a new tank.

[banman]

If you pull the sending unit, you should be able to see into the tank well enough to see how narsty things are in there...

diesel is so much more oily than gasoline -- you'd need a LOT of water sitting in the bottom of the tank a long time to really bogger it up...

As much fuel as you've drained already, you've removed any water since it sinks. When you look into the tank, you'll see how rusty the bottom is -- if looks like "flash-rust" I'd say forget about it. If it's heavy, flaky, 3D rust then I'd think about dropping the tank...

Now that you have the correct filters installed -- have a good seal -- are you running decent or still having problems?

[EastCoastCB]

Originally Posted by banman

If you pull the sending unit, you should be able to see into the tank well enough to see how narsty things are in there...

diesel is so much more oily than gasoline -- you'd need a LOT of water sitting in the bottom of the tank a long time to really bogger it up...

As much fuel as you've drained already, you've removed any water since it sinks. When you look into the tank, you'll see how rusty the bottom is -- if looks like "flash-rust" I'd say forget about it. If it's heavy, flaky, 3D rust then I'd think about dropping the tank...

Now that you have the correct filters installed -- have a good seal -- are you running decent or still having problems?

On my bus you can just open the fuel filler and shine a light in.

Is the chain on the fuel cap rusty?

OP- I remember telling you to look for any signs of a rusty tank! Those aren't fun. If yours is bad I'd start sourcing a used replacement. They're expensive as hell new.

[banman]

Originally Posted by EastCoastCB

On my bus you can just open the fuel filler and shine a light in.

Is the chain on the fuel cap rusty?

OP- I remember telling you to look for any signs of a rusty tank! Those aren't fun. If yours is bad I'd start sourcing a used replacement. They're expensive as hell new.

So interesting how different our "same model thomas fs65's are"
My 100 gal tanks centered behind the rear axle. Natives 65 gal tank is right behind the passenger door. My tank has a rubber filler neck about 3½ feet long to feed into the center of the tank...

To the OP, even after draining, it will be a 2 or 3 person job to comfortably lower the tank. OR you will need to learn to get creative with ratcheting cargo straps.
Try and post a pic of the inside of the tank after you pull the sending unit.
I may have more tricks up my sleeve for you...

[EastCoastCB]

Ah in that case I'd pull the sending unit and get a good look in from there.

[Mat7783]

Hi Banian: the bus cranks right up and idles perfectly. Bus leveled in driveway on blocks for conversion. After I get the tank issue resolved, I will take it fir a spin.

[Mat7783]

Hi EastCoastCB: cap chain is clean. A guy is coming over tomorrow to jack bus and drop tank for inspection.

[Brad_SwiftFur]

In my case I have a "30 gallon" tank (probably 35 actual) in which I observed the cap chain rust as well as the fuel float seems stuck. Now I could drop the tank and remediate the rust, but I *NEED* much more range than 30-ish gallons. So my plan is to swap out the tank for an aluminum one from a road tractor (including the brackets). In my case, mine is mounted between the passenger door and rear axle, and I have a maximum of about 54" to work with (it's a fairly short bus). I may be able to work a 100 gallon tank into the space, which would be an inch or two from the steps as well as the wheel opening.

[Mat7783]

From my tank, nasty