Valve adjustment question

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75gmck25

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I’ve always been told to shake the pushrod up and down to find zero clearance.

When you use the spin method you are trying to find the zero clearance point with your (un)calibrated finger tips and it’s hard to be consistent. When you shake the rod up and down its easier to find the precise point where it will no longer move. You can both feel and hear it. YMMV
 

CRM

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Well I spent the morning trying to get it running to no avail. Used the Jeep to tow it out of the way. I guess it's going to be unused for a while.
 

SirRobyn0

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Well I spent the morning trying to get it running to no avail. Used the Jeep to tow it out of the way. I guess it's going to be unused for a while.
I'm sorry to hear that Casey, if you were closer I'd come by and at least look at it and give advice. I'll let you know if any travel plans go your direction anytime soon.
 
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CRM

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Been a while since I've touched the truck. Went out today after work and adjusted the valves again from scratch. I now get a loud backfire at the carb air intake. I tried loosening the distributor just enough to move it with some effort and moved it back and forth to see if the timing was off. The backfire would go away but no start still. Maybe I should hook up the remote starter, pour 5 gallons of gas down the carb air intake, and watch it blow up........
 

SirRobyn0

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I've got an idea kind of. Would you be able to post a video of the truck trying to start it and maybe at a few different timing settings? One of us might see or hear something that might help. It's a thought anyway.
 

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No unusual noises really. The engine turns over with a normal sound. The only difference is when it back fires. Is it possible the distributor is in backwards?
 

SirRobyn0

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No unusual noises really. The engine turns over with a normal sound. The only difference is when it back fires. Is it possible the distributor is in backwards?
Backwards no. The firing order could be backwards, or the distributor could be 180 out. Have you considered that? Could the firing order be on the cap backwards?
 

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I just re-read the thread and I see you have considered plug wires installed on the cap backwards.

My reference shows a clockwise firing order of 1-5-3-6-2-4.

For giggles, hook your timing light up to #1, turn the key on and crank it with your remote start, you can disable fuel to prevent an accidental start if you want, disconnect vacuum to the distributor, point the timing light at the timing marks and see if it's on the scale. It'll flash much, much slower than if it was running and you'll need to be mindful that you don't overheat the starter, but you should be able to substantiate if your close on the timing that way, and if not you should be able to turn the distributor or 180 it or change what you need to, to get it to flash near where it needs to be. You could pull all the plugs out except maybe #1 so it's firing normally to reduce load on the starter, but you'll need to be mindful of the loose spark on the other 5.

Maybe that'll get you going again, and even if it doesn't you'll be able to rule out a timing problem for sure.
 

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