Trouble shooting fuel system. Was driving down the road when suddenly the engine just up andquit running. No sputtering or anything. It was like someone turned the ignition key off. Luckily Iwas only a few miles from home and was able to call a friend with a tow rope to tow me home. Checked the ignition system. All ok there.Fuel tank is full or nearly so. No fuel getting to carb. Found the fuel pump control unit under the dash and tested at its connector for 12v at the black with white stripe wire. 12v ok there. Jumpered that wire over to the black with red stripe wire (it goes directly to the in tank electric fuel pump) and turned on the ignition switch. Still would not get fuel to the carb and start. Could not hear the fuel pump running even after going around and bending down with my ear close to the fuel tank. To see if it made any difference, I gave the underside of the tank a good boot kick while the control unit was still jumpered and the ignition switch still on. I heard the pump run for a few seconds and stop. Kicked again and same thing. Tried starting the engine. It started and ran for about 30 seconds and stopped from lack of fuel. My hands are not small enough to reach in andget to the connector on top of the fuel tank and check it for 12v and corrosion. I can see it tho and it looks like a 2 wire connector.One wire is ayellow wire whichI believe goes to the fuel gauge sending unit in the tank and the other is the black with red stripe 12v power wire to the pump. It is frustrating trying to get to it. Gave up after skinning the heck out of my knuckles. Does anyone know where the electric pump gets its ground?Maybe its a grounding problem. Maybe it grounds by its mounting to the tank and then thru the tanks mounting to the frame. Maybe after 20 years I have corrosion between the tank and the frame. I am sureNOT looking forward to dropping the fuel tank down. Would just about rather take a whipping. Sure wish I could get my hands on the guy that decided to put fuel pumps inside the fuel tanks. Does anyone have any ideas or suggestions on how to proceed from here? Any help much appreciated .........Carl
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Apparently one can unbolt the truck bed and move it rearwards (or remove it) to gain access to the fuel sender and fuel pump, as an alternative to dropping the tank. I've always wondered if it would be easier to place wet rags over the top of the fuel tank and cut an access panel into the bed for this...(my B2200 has a bad sender). A reason most vehicles don't have access panels in truck beds or car trunks for this(old MPVs did) is that fuel pumps and fuel senders hardly ever go bad during the warranty period, and there's BIG $$$ in changing these things out, and a certain percentage of that business goes to dealerships...
Thanks Cusser for your reply. I will look at moving the bed back. Biggest thing to watch for there I imaginewould be not pulling wiring for tail lights, etc. loose. Another angle I am looking at is simply adding an external universal electric fuel pump near where the fuel line exits the tank and just down stream of the fuel filter located just behind the tank. I would power it with the same 12v wire going to the in tank pump. I would try and mount the new pump as low as possible in relation to the tank bottom and not protrude below the tank bottom. My one concern with that would be whether or not there is enough by-pass through the in tank pump. In other words, will the new pump suck fuel through the in tank pump with little or no impedence? I wonder if anyone has ever tried this? Compared to the outrageous price of the OEM in tank pump, the universal pump is very inexpensive. This one has very close specs to the OEM pump: http://www.partsamerica.com/ProductD...goryCode=3339K
The other way to avoid sucking thru the in tank pump would be to find a short elbownipple to thread into the tank drain plug hole and plumb it for the universal electric fuel pump. Finding the right metric threaded nipple would be difficult I think. I would have to devise some sort of rock guard or shield to protect it though. I will let the group here know how it goes.
Tested with new universal pump to see if there is enough by-pass through the bad in-tank pump. There was no by-pass. Could not find a 90 degree elbow fuel fitting with a 5/16" fuel hose barb that would screw into the same hole that the fuel tank drain plug bolt (10mm 1.25 pitch metric threads) does. So I made one. Had to buy a 10mm 1.25 die to re-cut the threads on a brass 1/4X1/8 male flare elbow. The total for the new pump and other hardware was 41 dollars. About 100 miles on the truck now since this mod. The new fitting on the bottom of the fuel tank could get knocked off during off-road use but I don't plan on using it off-road.
Pretty good. Are you getting some leakage under there, what's that in your photo? Could you make some sort of metal guard and bolt it in front of the fuel tank? Many electric fuel pumps are cooled by the surrounding gasoline. Most manufacturers choose not to engineer-in a trap door for access, as repairing these can be big business. That'smain reason I haven't repalced my own fuel sender unit, too much labor, so I use the trip odometer.
Actually dropping the fuel tanks in these trucks is not that bigof a deal. Once you get the filler and overflow tubes off. There are 4 more hoses( suction line, return line, 2 vacuum lines 1 to the engine and 1 to the check mounted near the tank) and 1 electrical connection, and 4nuts. My fuel sending unit was bad also, soI replaced it, by dropping the tank. I know you already have this truck running, but for future reference, it can be dropped in a couple of hours.