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Discussion Starter #1 (Edited)
In a 12k forklift, but it's a truck engine (came out of an 83 F350 airport stair truck).

Couple weeks ago, carb decided it didn't want to work anymore, was pouring gas out. It hadn't run very well in a while, so just bought a new carb ($80 on ebay) vs trying to rebuild a worn out one.

Put it on, fired it up, was running, but seemed rich (bit of black smoke). I didn't have the choke heat line hooked up (got the wrong fitting) so figured that wasn't helping things.

I was letting it warm up at idle and it stalled. Ran for maybe 4-5 mins. Well, that's it. Won't start now.

Thought it was flooded, but plugs are dry. Tried pouring a bit of gas into the carb, as well as ether, and it just to say sputters a tiny bit.

Has spark. Compression is fine. Nothing fell into the intake or anything like that.

Any ideas? This engine is simple, but I'm at a loss.

Actually have a 96 F350 with 351 with same issue... go figure!
 

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Do you have the same size jets in the new carb? Is your float bowl height adjusted properly? What kind of fuel pump do you have, mechanical or electric?

Sent from my SM-G920P using Tapatalk
 

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Discussion Starter #3
Mechanical pump.

Perhaps carb issue, but why won't it run off poured in gas or ether... seems odd.
 

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Mechanical pump.

Perhaps carb issue, but why won't it run off poured in gas or ether... seems odd.
You sure you have good spark? I've seen coils get hot and quit and then cool down and work again. Electronic ignition or points?
 

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83? Does it use the big spark box still? Duraspark? The two connector thingus
 

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if it does end up being that, get you a 4 pin GM module
the aftermarket duraspark boxes are shit

but you says you has sparkles
 

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New duraspark modules are cheap
 

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Discussion Starter #15 (Edited)
Tried it yesterday, thing fired right up.:confused:

Running way rich still, but I'll figure that out.

Not sure if the ignition is going bad, and is fine now, or what the deal is.
 

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and last an hour

4pin GM works with a couple crimp on spade terminals
I have found if it doesn't say GM or Motorcraft on it, it's probably junk. Just had an HEI module fry a month ago. A 30 year old stock one went into it's place.
 

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Discussion Starter #17 (Edited)
Had it running last night. Seems mostly a choke issue. I haven't hooked the heat pipe deal yet (need a fitting which I'll get tomorrow) so hoping that's it.
The old carb had a jerry rigged manual choke which never worked well.

Whoever put the engine in hacked the emissions and it had a TON of intake and exhaust leaks. All fixed now. Amazing how we've been running it for years like it was and it ran OK enough to never fuss with it.

The PCV was hooked to a blocked off port. Should it have full intake vacuum? (IE hook it to a port right off the manifold).

Other option is I can just vent to atmosphere.

I don't understand why it wouldn't run the other day. Would think it was way flooded, but the plugs I pulled out were bone dry.
 

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phenolic cam gear failure?

compression is fine or was fine?
It wouldn't even try to run if the cam gear failed. When they go they go all at once and they basically never go unless you put stiffer valve springs on a motor that's already got half a million miles.

The PCV was hooked to a blocked off port. Should it have full intake vacuum? (IE hook it to a port right off the manifold)
Unless you like sludge you should hook it to manifold vacuum.
 
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