Dodge Repair: 1976 dodge sportsman 1ton, accelerator pedal, vacuum advance


Question
QUESTION: Hi Roland. I have a 76 sportsman its a 318 and it chokes as your stepping on the accelerator.  What could be the cause of this problem?

ANSWER: Hi Dave,
It sounds to me like a mixture issue or a spark timing issue. On the mixture part I would wonder about the carburetor float level being out of spec or one of the fuel jets being partially clogged. Start by looking down the throat with the engine idling and then observe whether you see either no change of or a 'flooding' of gas spray entering the throat when you rev the engine, first gently then vigorously. Let me know if something looks extremely wet or dry.
Also check the air filter to see if it might be badly clogged up, light should be visible when held up to the sun coming through the folded paper.
On the spark timing, watch the action of the distributor vacuum advance mechanism as you rev the engine up and down to see if it seems to follow the change in the position of the throttle plate which you are manipulating via the accelerator lever (or by a helper doing the revving via the gas pedal). The vacuum hose from the manifold to the advance mechanism may be loose at one end or the other or the mechanism could be 'stiff' and not responding quickly.
Check all hoses attached to the intake manifold for leaks and verify that the carb bolts are tight.
If you have a timing light you could check to see if the timing at idle was according to spec or not, and that the timing retards quickly in response to the accelerator pedal manipulations.
Has this problem just grown in gradually or did it appear suddenly?
Unfortunately I don't have any shop manuals this far back.
Those are my thoughts, but I must admit that I haven't worked on a carburetor engine for quite a while.
Please read the PS below.
Thanks,

Roland

---------- FOLLOW-UP ----------

QUESTION: Hi Roland Dave again, I failed to mention that it idles fine the choking starts when the van is in drive. I replaced the air filter already. Could it just be that it needs a tune up real bad?
Dave.

ANSWER: Hi Dave,
Other than replacing the spark plugs, and changing the points in the distributor, what I suggested that you look into would be the things associated with a 'tune up'. How many miles are on the plugs? Have you looked at the vasuum hoses attached to the intake manifold and the carburetor for pissible leakage or disconnection?
I do have an '82 manual for cars that use the 318 engine so I can list the possibilities for what you called 'chokes' only that name is not used. I assume that it won't produce additional power when you step on the gas, but does it seem to be due to 'missing'/hesitating as the result of too little fuel of faulty combustion, or due to too much fuel (which is what I would call choking)?
Do you get smoke coming out of the exhaust pipe when that happens and is it black or blue?
Did this just start happening, or has it been going on for a while and just getting worse?
Do you typically do your own engine tune-up work and do you have test equipment?
Those are the factors I need to know more about to suggest anything other than going to a shop which has mechanics familiar with engines of that time frame.
Please 'rate' my answers and consider giving a 'yes' to a nomination of me to be volunteer of the month at Allexperts.
Thanks,
Roland

---------- FOLLOW-UP ----------

QUESTION: Hi Roland, question I have a 76 B300 1 ton van. I just replaced the Carb fuel filter and fuel pump. Still not getting fuel to the Carb. What could be wrong

Answer
Hi Dave,
Without a manual I have to guess. Is it an electric fuel pump, and if so is it humming when you put the key in the run position? It may only do that for a second or so, and if not then have a helper try to start it while you listen for the sound of the pump. If it doesn't hum then I would check out the fuses to find one that is either blown or might have a subtle crack in its internal wire. Also check for the presence of 12V across the pins of the plug to the pump when you are cranking it over.
If the pump appears to be powered, then see if you can find a fuel pressure test port in the line that runs from the tank to the carb. Check for fuel pressure to be present there. If no pressure then either the line is plugged or the fuel pump isn't working properly.
I wish I knew the specifics of the vehicle but those are my suggestions.
Please read the PS below and respond.
Thanks,
Roland