CK5
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Engine starts ok, but immediately stops:

I would think if the carb was "clogged up" with spiders or whatever else might be in it,it would not want to start up right away,you'd have to crank the crap out of it to get gas thru it enough to make it attempt to start..perhaps there was old gas that varnished up in it when it was stored,and only the accelerator pump is letting fuel pass,who knows..(I find it hard to believe)..

You can tap into the starter "crank" wire at the neutral safety switch,or where it passes thru the firewall at the bulkhead connector bu sticking a cotter pin in the spot the wire comes thru--its usually a 12 gauge purple wire..applying 12V to it will make the starter crank...(make sure to turn on the key before trying to look at the timing marks )..
 
One thing that has occurred to me although rather late. Its so basic to us old guys, I never even thought to suggest it.
If the jets are clogged, but the accelerator pump is still working, you should be able to keep it limping along after cranking by pumping the accelerator.

Every time you hit the pedal, it will squirt a shot of gas in the intake. To guys who grew up with carbs, pumping the pedal to keep it running is almost automatic. But a lot of folks who have come along after fuel injection got big don't do that.

I amazed a kid when I cranked an old Chevy van that he had been trying to start for a while.
It would crank and die, over and over. I climbed in, pumped the pedal a couple of times, cranked it over.
When it caught, I just kept pumping until it finally leveled out and ran. Main problem with it was the choke was stuck open.
But if your truck has a big vacuum leak under the carb, or other problems, you should be able to make it keep going for a little while with the skinny pedal.

If so, that should narrow it down to the fuel issue.
 
Tried starting it on the "new" timing setting; It wasn't as easy to start. Not difficult to start, just not as easy.

No effect on getting the engine to run longer.
 
Have you looked in the carb's inlet fitting to see if it still has the paper or bronze fuel filter in it?..seen those plug solid after sitting,or installed "backwards" and the fuel supply gets blocked..but you did say it ran good on the previous engine so....?...
 
Have you looked in the carb's inlet fitting to see if it still has the paper or bronze fuel filter in it?..seen those plug solid after sitting,or installed "backwards" and the fuel supply gets blocked..but you did say it ran good on the previous engine so....?...

May check that eventually, but it would take more than a few seconds to empty the bowl? See where i am going with this.........?

Immediate/desperate plan is to get a universal throttle cable/or find a way to manipulate the throttle arm to try to pump fuel in to see if that will keep the engine running.

4.3 throttle cables are not easy to find and you can't use a v-8 cable (too long) my source for cables hasn't been able to send me an original one yet.

This is getting ridiculous.
 
UPDATE:

Was able to keep the engine running by pumping the throttle arm (engine did not run smoothly of course, but did continue to run). Used a string tied to throttle arm.

What would this indicate?
 
ALRIGHT! Finally a light!

That means that the carb is not feeding any gas to the engine in the normal way. You kept it running on the accelerator pump only. The jets are not supplying any fuel.

It also means that you have fuel in the bowl, because that is where the pump gets it's supply.
It could be really low and might not pick up with the jets, but unlikely.

Something stopping up the jets in the carb is certainly possible and may have to be checked, but by far the most likely since you have swapped the carb, is a massive vacuum leak.

Looking in the top of the carb, you can see the choke butterflies right on top. The next set down is the throttle. One end of the throttle shaft is hooked to the accelerator pedal, and the other side sticks out slightly.

Get a flashlight and mirror, and carefully examine all sides of the carb below that throttle shaft.
Look for a big hole that a hose should hook to. Most likely is the hose to the brake booster.

If you don't see a hole, then odds are the gasket between the carb and the intake is torn or bad.

Actually there is one other thing that could cause this. I have only seen it once. Are you sure that the carb you put on matches the holes in the intake?

I honestly saw a guy manage to bolt a two barrel carb onto a four barrel manifold with no adapter.
Actually he had an adapter, he built one so the studs would line up. But it left part of all four intake holes exposed...........

Either way, bad carb, or massive vacuum leak.
 
UPDATE:

Finally running----i put the "junk" reman carb that came with the engine back on. It starts and keeps running no problems.


Thank you everyone for the help.
 
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