1985 K20 350 Lost Spark While Driving

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Bextreme04

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Eric
Truck Year
1980
Truck Model
K25
Engine Size
350-4bbl
Here’s how it failed. When I pulled the new pump the arm was just flopping.

This was the inner piece of the arm that rises on the pump shaft inside the pump. I turned it over and shook it and this piece fell out.

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Grumpy

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Saskatchewan
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Daryl
Truck Year
1985
Truck Model
C10
Engine Size
350
When mine failed, it was a brand new carter pump on a freshly rebuilt engine. Less than 500 miles and less than two months old.
New parts fail too. That's why there are dealerships for new vehicles. Years ago, I worked on a tractor that had a failed hydraulic pump - after replacement, same thing..... so another new pump. Four pumps and two weeks later, a fresh bulletin comes in regarding a particular brand of hydraulic pump assembly, and they produced a thousand units with faulty compensators (built in.)
 

Bextreme04

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Engine Size
350-4bbl
New parts fail too. That's why there are dealerships for new vehicles. Years ago, I worked on a tractor that had a failed hydraulic pump - after replacement, same thing..... so another new pump. Four pumps and two weeks later, a fresh bulletin comes in regarding a particular brand of hydraulic pump assembly, and they produced a thousand units with faulty compensators (built in.)
Exactly... hence my comments about verify everything and start with the basics. Just because a part is new, doesn't mean it didn't go bad.
 

fast 99

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350
Check the 2 small wires coming out of the pickup coil. They will occasionally break right at the coil, check for power to the ignition coil marked battery at the cap, remove the rotor, turn it over, look for a burn through.

Not that it's your problem but did you put a small dab of dielectric under the module?
 

potent rodent

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indiana
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butch
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1500
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350 and 305
did u check your coil while cranking it over? if its getting fuel then it could be coil / pick up for the coil or bad module, may not be getting 12 volts
 

klarster

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Zac
Truck Year
1985
Truck Model
K20
Engine Size
350
UPDATE: My buddy volunteered to come put an extra set of eyes on the truck. Discovered that I suck at life and I do indeed have ample spark! Just not in the right order??? Either I screwed up putting the distributor shaft back in the engine block or paid no attention to what the frick order the plugs were in. Either way, easy enough fix I'm the end. It seems clear to me that replacing the cap and rotor fixed the original issue, and I just created another problem by putting the thing back wrong. That'll teach me. Cheers and many, many thanks to all you fine folks who helped me along the way!! In true fashion I continue making more new mistakes while learning from the old ones
 

wlwarnke

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Helotes, TX
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William
Truck Year
1983
Truck Model
K5
Engine Size
5.7
Doesn’t everyone have 18436572 tattooed on the back of their hand?
 

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