I have a 1988 F-250 XLT lariet Diesel with a 7.3 engine. My truck will start sometimes but then quickly die even at high RPM's (2000+). My truck does not start afterward but sometimes starts when some electrical wire are jiggled. These wires are under and behind the driver on the frame. They feed into some electrical box. What is this box and does it have anything to do with the problem? Thanks.

 

The symptoms sound like air in the system via a bad oring or seal on the fuel system or filter header. Air entry into the fuel system will allow fuel to drain back to the tank selected. The IP has enough fuel to start, then starves until the system is re primed when you crank it over.

The box you speak of may be the the Fuel Selector Valve if there are 3 sets of 2 lines going to it. If this box is on a single fuel line it may be an electrical fuel pump.

 

I had this problem 6 months ago and the jiggling of the wires fixed it temporarly. The problem just started again. I will have to check later on how many wires are box. I have two tanks on the my truck.

 

the diesel powered trucks use a 6 port valve to supply and return fuel from the selected tank. It is fairly big with 6 fuel lines hooked to it. You should be able to hear it switching with someone helping you work the tank selector with the key on switch while you are beneath the truck. You may be experiencing problems with that or there may be an inline electric fuel pump installed after market because the previous owner had fuel leak down problems from air intrusion. The air gets in around the o rings beneath the injector caps and may or may not show fuel leakage at that point. It just seems to be the nature of the beast. Be careful that you DO NOT crank on the starter too long at any one time. They are sensitive to heat. You may also be experiencing a problem with the glow plug system and that will also cause hard starting, but the symptoms lean towards fuel supply. Try parking the truck with the nose low and see if it helps. Good luck and let us know how ya make out.

 

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I know that there is a problem with the glow plug system since my plugs were fried after being replace in about 6 months. Now for the heating of the plugs the light is on for possibly half a second before the clicking. I did the light test on some of the plugs that were easily accessable and some were dead. When the vehicle is running properly but without the glow plugs it will start up within a couple revolutions after neing plugged in over night. Currently I am away from an electrical outlet because I am at college parking and my glow plugs are not functioning is there another way to start my diesel. I have used starting fluid (the cheap less flammible stuff) as a substitute when needed but I try to stay away from the suff when ever possible. I have heard the the high heat caused from the fluid will kill the glow plugs (not too worried because they are already fried) and also it will drive the lubrication from the cylindar. Is this true? Are there safe inexpensive alternatives to the fluid? Currently I cannot afford many maintenence and can barely afford fuel because I am a poor college student so any advise on how I could fix it myself would be great. I am fairly familiar with working on vehicles and I do all of the basic repairs and then some. Currently I drive about once or twice a week depending on my schedule and needs but this truck is my work truck and everything else truck since it is the only vehicle in my family to haul our trailers (when I am at home). It is a key part of my family for multiple purposes. Back to the topic, I do not remember the electrical box having multiple fuel lines but some appear to run past it (some parts are hard to see with the fuel tank in the way). As soon as I can afford it I will probably be getting some new plugs. What may be the problem if the "Wait To Start" light is on for half a second befor the clicking starts. Also I head that there is a way to bypass the controller and have a push-button switch in the cab to manually control the plugs. Does this work and is it a feature that is cheaper in the long run or more expensive (Cost of cooked plugs or new controlling parts?)? I will later today if possible look at the switch and try the suggested. Again, all posts are greatly appreciated so thanks.

 

If you tested some of the glow plugs and they are not testing, they are toasted. That is the reason for the short light. If you change the glow plugs get the motorcraft beru plugs. You should be able to see the fuel selector valve inside the frame rail ahead of the tank or look for two bolts about 1.25 inches vertical separation on the outside of the frame rail, that should be the selector valve. Or listen for it changing while working the switch.
If the glow plugs themselves arent working, no manual controller will help you out.

 

I found the fuel switch and tried shoving in the wires and checking to see of they were loose. The box makes a clicking sound when I switch the tank switch but I think this is normal. I should have checked for the clicking sound before I messed with the wires but did not think about it, The problem could be fixed by pushing in the wires but since my batteries are dead I do not have the power to start my truch anyways. A question; I have two 850cca batteries in my truck and they do not seem to be able to put enouch power to start my truck even in cold weather. Would it be possible to put an extra battery or two either up front (if room) or in the back with like some 2 or 4 gauge wire connecting them? Currently where I am at there are cold temperature usually ranging from about 0-40 each night (spontanious weather). I know the cold weather affects batteries and I did not have a problem last year (had working glow plugs and no significant problems for basic operation). Is adding and extra battery or two a possibility for raising the CCA?

 

Batteries get old and loose there cranking power over time, you may want to get a shop to do a load test on each battery individually, should be cheap and easy to have done. Make sure all the terminals and ground connections, including the frame are clean, tight, and free of corrosion.
Mine has quit after starting due to loose and corroded connection on the IP fuel soliniod, or if the glow plug controller has not quit cycling and the alternator is not up to full voltage it will sometimes quit if I start driving to soon. These trucks, especially with the automatic trans like to have all there electrics in good shape and the voltage up to 14.5 +/- on the alternator output.