Hi I have a 1983 f100 with a 300-6 in it. My vaccume advance has no vaccume signal at the ported vaccume port at all. I know theres no vac there at idle but its not there with the rpm raised eather.

the motor is from a 1994 and has bean converted to carb with a in line electric fuel pump.

The truck has had the pollution controll removed (I live in manitoba so that's no prob here)

One other thing I wanted to ask is im having a prob with the starter the preveous owner has it mounted at a angle with a peace of 2x4 between it and the oil pan.
If I remove the wood the starter just grinds. Im wondering if they used the 94 flex plate (I have the C6 trans in the truck) or if its the wrong starter. Basically im trying to find out if a 94 flex plate was used if that would be the problem or if its the starter.

 

Is the lack of ported vacuum at the carb, or after it goes through the hose and maybe a temp switch? If at the carb I would blow compressed air through the port to clear it out.

On the flex plate and starter, I have no way of knowing what one you have. I would pull the starter and examine its teeth as well as those on the flex plate. It sounds like one or both may be bad.

 

Well I replaced the vac hose today from the dizzy to the carb its just a straight hose to the ported vac.
but no vac what so ever at the ported vac port evin either the rpm raised.
I only have one spot on my carb for vac, and the P.O. has removed all pollution controll so the only things needing vac is the dizzy, dash vents and trans. Any check valves and vac switches are long gone

 

Time to hit the vacuum port with compressed air. I wouldn't go overboard, but see if you can open it up.

 

Welcome to the forum, F100XL300I6!

Regarding having no vacuum @ the carburetor port, you can do as Gary suggested ["blow compressed air through the port to clear it out"], rebuild the carburetor [includes a thorough cleaning], replace the carburetor or switch to manifold vacuum and adjust accordingly.

Good luck!

P.S. Different year carburetors are set up differently. This is not to say that your single port should never have vacuum, but some have different amounts at different engine speeds [varying calibrations]. On my 1986 with the six cylinder engine, the carburetor is from a 1970 F350. The port has 5" Hg [vacuum] at idle and goes up as the throttle plate is opened.

Hmmm... some carburetor base gaskets have a tiny hole for access to the manifold vacuum. The gasket hole lines up with a tiny hole in the base of the carburetor. Perhaps the gasket is incorrectly installed [reversed] or the wrong one for your application?

 

I thought the electronic carbs didn't have a ported vacuum port. If that's true and that's what he is running, that could be the explanation.

 

I was assuming a non-emissions carb in use but that's a good point... what brand and model number of carburetor is this....

 

I'm just going by what he said - "ported vacuume". If he's wrong then.....