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Discussion Starter #1
I had a '82 C-10 shortbed with a 6.2L and a 4spd manual OD trans. It ran like a top for me. I sold it after getting a newer truck.


It left it's new owner stranded in the middle of no where a couple weeks back. She proceeded to melt the insulation off the battery-starter cable while trying to start it. That managed to screw up the connection between the main positive feed to the rest of the truck.


After much head scratching and cursing of GM engineers,
I figured out why it wasn't getting power. Then I cracked an injector fitting loose and cranked it over until it got diesel squirting out of the loose fitting. It cranked fine but wouldn't start on the starter. It did fire up and ran great when we pull started it.


I replaced the burnt cable, re-routed the main positive feed directly to the positive battery terminal, and back-flushed the fuel lines from the tank switching valve to the tank with lots of compressed air (even remembered to take the gas caps off so I didn't rupture the tanks).


The truck ran awesome after that. The power used to die off after 3,000 RPM(guessing, no tach), but after flushing the lines out it kept pulling pretty good all the way up. I figured maybe the pickup screens were clogged and restricted fuel flow.



Tonight she called me from the side of the road yet again. Same issue, it just died out and wouldn't start. I'd installed a small electric diaphram pump before the big, under-hood filter, and I instructed her on how to empty the water trap in the filter and bleed the air out using the pump to get the air out of the filter. No avail, it still wouldn't start. It's deffinately not out of fuel this time.



Any ideas? Any last things I should try before dropping and cleaning out the tanks, pressure testing the fuel lines for leaks and replacing the filters? (I replaced them about a month before I sold the truck, they should be OK).


Out of curiousity, where is the valve that shuts off the fuel when you turn off the ignition? Is it on the pump it's self or what?


Sorry this post is so long


Mike
 

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Does it surge before dying? I would also change the filters.


The fuel shut off is on the top of the pump. It is a single wire. I think it may be pink in color. When you apply 12volts it opens.


Right or wrong, I use WD40 to start mine when there is air in the lines, ran out of fuel etc.


Make sure the brushes are in good shape on the starter. It may be dragging. Your batteries should be in good shape. If fully charged, either battery should be able to turn the engine over by itself. I have fixed a few 6.2 starting problems with batteries, cables or repairing the starter.
 

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That is one of those deals you need to be there when it acts up or you'll just keep throwing money at it and never find it.


Could be the fuel solenoid, could be the injection pump. I am sure the starter is in bad shape if she melted the insulation off the cables.


Could be the ignition switch, we can guess all day.
 

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Discussion Starter #4
Professor: I don't know if it surges before dying, but I'll ask her today. The batteries are less than a month old. I know the guy who owned the truck before me replaced the starter. I've heard they're notoriously weak, which is strange considering the size, weight and cost of the damn things. This one does seem to be OK, it cranks the engine over pretty fast.


Traveler: I just recently started to wonder if the ignition switch or fuel solenoid is acting up. I'll jump 12V+ to the solenoid and see if it starts. The pump should be in good shape, it has a sticker from the local injector/pump rebuild shop on it's case, so I'd imagine it's been rebuilt.


So today I will try these:


A: jump 12V to the solenoid, and see if it starts, hopefully indicating weather or not it is an issue with getting power to the solenoid. If it's still dead:


B: Replace the filters (good measure), bleed the fuel system, and try it again.


Thanks


I'll let you know what happens.
 

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Discussion Starter #5
As best I can tell, there's an air leak in the line between the right tank and the switching valve. I discovered this while bleeding the lines after backflushing yet again. There's a section of clear fuel line, and I noticed that the bubbles just wouldn't quit showing up while switched to the right tank. It takes a while, but eventually enough air gets in the system and it just quits pumping.


Makes sense that it ran good for me, I pretty much ignored the tank switch and ran on the left tank for the entire year I owned the truck.


Thanks for your suggestions
 
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