My truck has recently developed a hard starting problem after sitting for extended period, up to a week or more. It will start right up but immediatly starts surging, then stumbles and stalls. Then it takes an extended amount of cranking to restart it and after that its fine. It only does this after sitting for about a week. If it sets overnight it starts and runs normally. I put the truck into storage every winter and this spring it started right up and never missed a beat after sitting for about five months. This problem just started within the past month or so. I replaced the return lines and injector caps last year and there are no visible leaks anywhere and the engine does not smoke when running. It just seems to lose its prime after sitting for awhile. Any ideas where to start, other than drive it more often? [img]/ubbthreads/images/graemlins/grin.gif[/img]
i have the exact same problem but for me it only takes a couple hours. i have tried feathering the gas while it initially starts and sometimes that works and sometimes it doesnt. i too thought it was a leak somewhere but i cant find one.
sorry i dont have an answer for you but im looking for one also [img]/ubbthreads/images/graemlins/frown.gif[/img]
i just replaced the lift pump and the line that goes from there to the fuel filter. im still having the same problem. would old cracked up return lines cause a hard start? im starting to run out of things to fix with my fuel system [img]/ubbthreads/images/graemlins/depressed.gif[/img]
First thing is to always replace all the rubber associated with the fuel returns. Lines, O-rings, and I like to replace the caps as well. If the problem persists, check the schrader valve on the fuel filter head, and then suspect the fuel return line to the tank. You can always put a piece of clear plastic hose on in place of the one between the filter head and #1 injector area to watch and see where the bubbles come from.
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93 F250 7.3 IDI S/C XLT 4X4 E40D 3.55LS, Captains chairs, Tutone Mocha, Leer 48" Hiboy cap, FR & RR hitches, full DeeZee running boards. Factory ordered/delivered Jan 93 has 160K+, it's basically a stock truck with all the Ford options, just no disc player.
Toys: 26'Jayco FK TT, 18'Sylvan Pro Fish.
Two things. Make sure the fuel filter is on TIGHT, also make sure that you have a SEALING valve cap on the schraeder valve. Schraeder valves are made to hold pressure, not vacuum. The proper valve cap will have a little rubber gasket inside, many do not.
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1985 International rollback, 6.9L 5 speed "Li'l Big Truck"
There is a check valve that screws into the filter head and drains into the return line. If it goes bad it will pull air into the filter head. Try removing it and see if you can blow thru it, if so then it is bad. This is very common. Each fuel tank pickup also has a check valve built into it. See if it happens on each tank. They are like inverted funnels that eventually fall off and the truck will run out of fuel around 1/4 tank or so. This will allow fuel to gradually drain back into the tank.
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90 F250 SC 4WD, 7.3 IDI, D60 FRT, FFLT 10.25 R, almost 400K, many updates and rebuilds over the years.
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