All,
Worked on the aforementioned truck today. Got to experience the problems
first hand.
It's an '86 GMC Sierra 3500 Dually Pickup with a lifting dump bed and a V8
(I think it's a 350 with a 2 barrel carb). It runs fine on straight and
level road. Plenty of power. Within 100 feet of driving on an incline
(even 10 degrees), the engine seems to die. No power, although it
continues to run. I get a brief surge of power, then nothing, brief surge,
then nothing. It smoothes down once we get the speed down to 25 or 30 mph.
Things I've checked.
Fuel Filter at the carb - changed a dirty looking filter.
Fuel screen in the tank.
Exhaust - new dual exhaust with NO catalytic converter
I tried to check the timing, but the timing marker on the timing cover is
gone. There seems to be plenty of power when power braking it (giving it
gas when your foot is on the brake), so I would think that timing isn't an
issue.
There's a hard to get to mechanical fuel pump, so I was unable to check fuel
flow from it. How often do the mechanical pumps go bad?
Also, I tried going up the hills in all gears (it's an automatic, so 1, 2
and D) and it gives trouble in all of them. Even first. On the straight
and level, the owner said he's had it up to 70 mph on the highway with a
load and no problems.
Is it me, or does this seem like a fuel issue? Or can it be transmission
related? Does it sound more like a fuel delivery issue, or a carburation
issue?
Sorry to bomb the lists with this again, but I need to use this truck this
coming week.
Thanks to all who offered their ideas on Wednesday. Anyone have anything
else I should check? And no, the answer's not "Get a Ford." <grin>
Mike
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/// (If they are dupes, this trailer may also catch them.)
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