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Old 06-06-2012, 10:21 PM   #1
86c20
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Question 6.2 hunting for idea

truck is a 83 6.2 th400 4x4 burb. truck has been setting at least 2-3 years. glow plugs stay on unless unpluged fast ideal seems high and when she kicks off she will hunt and wont smooth out bring it up and runs great. cant do a road test as has no breaks yet also motor is supposed to be rebuilt. could it be the pump is not adjusted right? anythiing will help thanks, mike
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Old 06-07-2012, 12:20 AM   #2
rcbildr
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Re: 6.2 hunting for idea

IIRC 83 has the old style of glow plug controller. Sounds like it's not working properly, its probably best to wire up a push button control for it....there's a lot of write ups on that. I would dump a can of seafoam in the tank and replace the fuel filters and run it for a bit and see what happens.
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Old 06-07-2012, 06:36 AM   #3
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Re: 6.2 hunting for idea

Quote:
Originally Posted by rcbildr View Post
IIRC 83 has the old style of glow plug controller. Sounds like it's not working properly, its probably best to wire up a push button control for it....there's a lot of write ups on that.
X2. Did this on mine with a F*rd starter relay, mounted it to the left rear intake studs with only a little opening up of its holes (threw away the EFE/EGR when I went to the J code intake), 4 gage feed wire, $5.99 momentary push button under the dash, 6 ft of wire, and boy is it better. Mine is an 87 with the later controller, left the controller in parallel as sort of a timer, when it clicks off I give it another 10 secs of glows (I use 10g slow heat self-limiting glows so need a little more on time). It fired off on the 2nd rev last week, after sitting since October.

The hunting is an injection pump wear problem, sloppy advance. Mine started to do it at low RPM light load, like 35mph on cruise in the city. It got progressively worse until finally I changed out the pump. The cold idle being high, probably all the idles are high because they turned up the idle to try to hide the worn pump hunting problem. The Seafoam may help, and you can drive it with the hunting, but the pulses aren't good for your drive train. Sooner, not later, you'll need a pump.

BTW the next thing you should see is fuel dripping from the advance shaft at the bottom of the pump. A reseal kit is unlikely to fix it, usually it's worn and the pump needs rebuilding.

Welcome to 6.2's, I get 23mpg mixed driving on my fully loaded 87 R10.
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Last edited by D13; 06-07-2012 at 06:43 AM.
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Old 06-07-2012, 01:16 AM   #4
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Re: 6.2 hunting for idea

Updating to the newer 1990's glow controller is as easy as bypassing the early unit.
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