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View Full Version : 1984 Converted to electric fuel pump & now have new problem



ccole
08-26-2007, 18:12
Hello all-
My mechincal fuel pump was acting up on my 1984 w/6.2 (surging at stop signs, hard starts, etc)...so, I converted it over to an electric fuel pump. It had worked excellent for 3 days, but now a new problem has arised. I was driving it around in town (and was running great) and stopped at the grocery store. I came outside and tried to start it back up (it had been sitting shut off for about 10 minutes)....and no fire. No "raw" smoke in the exhaust while crank the motor either. So...I cranked until the batteries started to get weak and i gave up. Went home and got the duramax and put the jumper cables on the 1984 and cracked (2) injector lines on the engine. (thinking maybe the injection system had air-fuel locked). I jumped in and barely hit the starter and it fired up immediatly. Went ahead and drover her home and let it sit for about 30 minutes and went out and tried to start it again.....same thing. Good crank, but no fire or no raw smoke in the exhaust. Any ideas what is going on here? The new electric fuel pump is pumping good flow and I can also crack the plastic valve on top of the fuel filter housing and diesel fuel spits out. One thing to mention-- I tapped into the heavy gauge wire that goes to the top of the injection pump for the shut off solenoid to engergize my new electric fuel pump. Is it possible this fuel pump is drawing too much and not allowing the solenoid to operate as it is supposed to? Its the only thing I can think of... What do you guys/gals think is going on here? Thank you in advance!

HammerWerf
08-27-2007, 08:30
ccole,
I am suffering the same symptoms as you. How many miles on the injector pump in your '84. Mine has about 160,000 miles since the last rebuild.

What I am expirencing is on HOT days, >95F, my truck does the same thing. Crank with no start, no smoke. What I think is happening on mine is the IP gets really hot, and the clearences in the High Pressure pump open up, allowing the fuel to leak out of the pump. The fuel in the pump gets hot, anf 'thins' out, making it even harder to pressurize. IP can't build up pressure to overcome the injectors spring 'pop' setting.

I have found that getting the heat out of the engine compartment cools the ip down enough to get a start. I have found for mine i need to have the glow plugs heat up for a more reliable start.

If you car is parked in a safe location, but don't want to be noticed, just open the hood to the safety catch, and this will allow enough heat out, but this method takes a while (thinkd hours).

My batteries are a bit weak, so that's not helping any.

HammerWerf