Bullet22r

The problem im experiencing is the truck has a really rough idle as in it would sound fine for a split second then it sounds like it misses a bit then comes back and repeats. I have replaced the old carburetor with a rebuilt one from my local garage, new rotor, fuel pump, ignitor, fuel filter, spark plugs. I have check for vacuum leaks by spraying carburetor cleaner around the vacuum lines and the idle doesnt seem to change. Please any help will be greatly appreciated.

slow-mo

Is this a new issue?
Did the engine do this prior to replacing the parts?
Is it occurring with a cold engine or at normal coolant temperature?
You say this occurs at idle, but does it stumble at speed?


With those questions asked, a couple things come to mind.

- Check your timing.
- Check all the rubber vacuum hoses for leaks.
- Check the fuel level in the float bowl via the sight glass. It should be in the middle.
&
- You still may need to fine tune the new carburetor's fuel mixture for your engine.

Bullet22r

Yes this is a new issue this was happening prior to only when i replaced the carburetor which was about 2 days ago and the problem started about 4 days ago way after replacing the other parts when the engine is cold or up to temp it still has the problem. When i check the float in the middle timing is okay no vacuum leaks idk what to do

Mr.Utah

x2 to what slo-mo said. Some vacuum leaks are very difficult to notice. If you have not replaced all your vacuum lines, you should probably do it.

Bullet22r

so i went ahead and pulled every one of the vacuum lines and replaced them with new ones from my local auto parts store and the problem is still there i have check egr valve it is not stuck open but i went ahead and blocked just in case. and let me correct myself from what i said from my last post it will start up fine but as the engine warms up it the idle goes rough

Bullet22r

okay i just stumbled across something i drained my gas tank thinking there was crud in the gas, there wasn't, but anyways i started the engine up to see what happens at first the same thing happened rough idle and i thought oh well and turned it off and it seemed like it "dieseled" a bit and so i restarted it and it ran smooth and when i went to shut it off it didnt diesel, i checked the float and its still in the middle im really confused..

Mr.Utah

check your timing, adjust idle on carb, re-check timing. Is your vacuum system hooked up correctly? If its a carb/choke issue, consult Slo-Mo

slow-mo

Hmmm...the Idle Cut Solenoid is supposed to prevent that "dieseling" condition. The solenoid will close off the fuel passage in the carburetor to stop the engine NOW, kinda-thing. Its also related to emissions but that's another story.

Well, that's another thing you'll have to check. Since you have a new (rebuilt) carburetor, the solenoid should be good. But you'll definitely have to confirm its operation.

Basically the factory service manual say to remove the solenoid from the carburetor and apply 12 volts to it. If you hear a clicking noise then the plunger is working. The solenoid plunger is held within a metal semi-mesh, it's actualy just some holes to allow the fuel to pass through. You wont readily see the plunger as it is hidden inside that mesh thingy, yeah I know technical jargon - thingy.

So if you hear the click, then that's supposed to mean that it is OK. I can't remember if the book says to test for resistance or not. You'll need to double check if it asks for resistance test.

To remove the solenoid, you'll have to separate the two electrical wires from the electrical connector. Then you can spin it off freely. The electrical connector also contains the choke wire and the Outer Vent Control Valve (OVCV) wire.

Bullet22r

after a couple of minutes running the symptom came back now im really stumbled.

Slow-mo yes it seems like the solenoid is working cut the two wires and tested it on my battery and i do hear clicking noises.

I was thinking of re doing my whole upper end since i am getting a bit of an oil leak at the front end of the cylinder head.. but do not have the budget to do it yet..