4BT Fuel Problems.......!

[JimmieD]

Hi guys,

Starting this thread in case some other folks have the same problems in the future.

I installed a 4BT in a '67 Dodge D-100 Town Wagon and it's absolutely GREAT, when it starts :~ ( At the time of conversion the 25 gal. tank out of the donor van was installed, and the 3/8" fuel delivery lines with 1/4" fuel return lines were used. A new Fleetguard FS1221 filter [best one to use] was installed and engine was disconnected for about 2 months or so.

Would NOT start! Filter was filled with fresh clean diesel when installed. Tried pumping fuel manually with the lever on the lift pump [fuel pump on a gasser]. Engine has to be at the right position in order for the lever to work. If it doesn't pump or doesn't have a feeling of resistance [more than its return spring] then you have to bump the starter 'til it does.

NOTE: there's a fuel shutoff solenoid on the Bosch VE injection pump which has a single wire going to it. This must be connected to a wire that is hot at ignition 'Run', and key must be in 'Run' position in order to pass fuel to injection pump.

I bled the fuel line banjo fitting coming out of filter housing going to VE pump and got lots of bubbles, then clear fuel. No start. Then bled all injectors and got lots of air bubbles. No start. I took another look at FS1221 and decided I might have tightened it too tight so loosened it some. Engine tried to start.

Finally discovered that there is a fuel line entering the very top front of VE pump, coming directly from lift pump. Hooked up a remote starting switch to solenoid's smaller control terminal and to + terminal of battery. Cranked starter while cracking open this pump fitting: INSTANT START! Figured the problem was solved by bleeding this fitting: NOT! Would not restart until fitting was bled again.....

Ordered a new lift pump. Stock they come with a nice Carter pump, or possibly an AC Delco. I ordered a fuel pump for an '89 1st Gen W-250 CTD truck from Checker/Shucks/Kragen and got an Airtex built pump under the brand of Master, P/N 1407. Perfect fit and works fine. Still have the same problem with new pump....

I think I may have bent fuel filter cannister or damaged the sealing ring so going to pick up a new one when I go to the big city today. I'll post again if this solves this pesky problem!

[warlock440]

Jimmie

I do not know what the Fuel filter on the 4BT is like but I had a 94 Dodge CTD and had a similar problem after changing the filter.. The 5.9 had a "Disc" between the filter and the (IIRC) Fuel heater.. The disc had an O-ring on the top side that was damaged.. Apparently when I took the filter off the disc came loose too and when I put the new filter on it tightened back up but also twisted the O-ring.. The engine was very hard to start when it had set for a couple hours but ran good once started.. What was happening is when it sat it would draw air in allowing the fuel to return to the tank but sealed good enough to prevent a fuel leak..

[Sickcall]

I don't know where you have your fuel pump located but it sounds as if you have a leak in your fuel supply somewhere between the tank and the pump. Is there some way for you to test it? Can you put a small amount of air pressure in it and do a soap test for bubbles? Maybe you could hook up a vacuum gauge on the suction side. What would happen if you put the pump suction right to a fuel can and bypassed all the suction stuff? Just some ideas to kick around.

[JimmieD]

Thanks for the tips and suggestions, guys. I had an extremely challenging day revolving around finding another fuel filter. Finally found one at the 5th shop I checked. Tomorrow I'll be putting it in and trouleshooting. THANKS!