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Doomsday Truck rolling start unsuccessful

3K views 22 replies 12 participants last post by  E TEX RAM 
#1 ·
So after the whole problem of not starting it turned out to be the alternator voltage regulator went bad so my batteries weren't getting recharged. Anyways long story short...

I thought since my 98 is a manual 12 valve and being a mechanical injection pump and stock mechanical lift pump :thumbsup: if I was rolling down a hill I could just drop the clutch and she'd start... However, after three tries this still didn't work :confused013::S: Yes my key was in the on position. I was going about 20 mph and dropped it in 3rd then in 2nd on the last try. Can anyone explain why this didn't work? :confused013:

By the way, this did work when my batteries had a charge, alternator was working yada yada and my starter was just stuck. Thanks in advance!
 
#5 ·
Did you turn the key to "start" or stop at the "on" position? I think it has to be turned to "start" for the solenoid to get power.
Therefore it will need enough power to move the solenoid.
 
#7 ·
Your batteries have to be charged for this to work. If you are unsure put a meter on your batteries and I would be willing to bet they are at 9v or less. Hence fuel solenoid not being able to open.
 
#8 ·
just put a manual choke cable on the FSS. Problem solved, doomsday status achieved
 
#12 ·
Even with good batteries the fuel shutoff solenoid usually wont do the initial pull up without the key being turned to start first. It takes quite a bit more amperage to pull it up than hold it. There are 3 wires on the solenoid- 1 is start/pull up the other is key on/hold and then a ground
 
#13 ·
My 96 would never roll start. :confused013: The motor would turn over but never catch fire. I tried on multiple occasions.
 
#14 ·
The FSS is a dual coil unit. One coils pulls on and the other holds on. For the pull on, batteries have to be fully charged and key has to be turned to the start position. The wire that feeds the starter solenoid also feeds the fuel relay. Once FSS is pulled on another circuit feeds the hold coil. This coil uses less power.

If batteries are weak, try turning key to on then reach in and manually pull FSS on. If it stays up then there is sufficient battery power. If it springs back down batteries are too weak.
 
#18 ·
Will definitely have to give that try but if I just tie it how will is shut off?

It is having problems shutting off anyways... can turn it off and it will run anywhere from 30 seconds to 5 minutes with the key off. I tell people I have a turbo time. :hehe:
 
#21 ·
I had a problem with my FSS. I used a rope to turn on n off. I bolted a hook to a fender bolt. I tied a rope to the FSS and put a loop on end of rope. I would then pull the FSS on and put the loop on the hook to hold. Turning engine off was just pulling loop off hook and releasing. I now have a cable to control FSS.

If you are saying that the engine runs on after you turn off and remove the key, then you may have a starter solenoid contact issue. When the solenoid contacts are worn it may stick in the on position. This will send power to the fuel relay and the relay sends power to the FSS pull on coil. So key off and engine runs on because FSS pull on coil is still energized. If this is the problem you need to fix ASAP. If not you may burn up some wires and some components which may be costly.
 
#22 ·
Haha, that is some true engineering right there on your cable.

Yes, that is what's happening. However, I don't think it is my starter anymore as I just had to replace the factory one in two weeks ago. It was staying on (running) before and after I replaced the starter. What other wires and components are you referencing. The starter was costly. :banghead:
 
#23 ·
I was referring to the starter n solenoid, the fuel relay, the FSS, the wiring between all and any thing else that may connect to this circuit. If the starter is new then I would check the FSS for cleanliness. They can get dirty and hang up. The FSS is spring loaded to the off position. You might try, with key off, pulling the FSS up by hand and releasing. See if it releases easy or if it hangs up. If it hangs up you may need to clean it.

If you think it may be the starter circuit you may connect a volt meter to the circuit. The circuit should only have power when the key is held to start. When you turn the key to on or off the circuit should have no power. If it does have power with key in on or off then you have a problem.
 
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