I have a 84 D100 with a 225. When it is cold it runs ok but when it warms up it wont stay running unless I'm feeding it fuel. I found where it was missing a vacuum hose running from the air cleaner to the choke pull off and after I replaced that it would run a little better but it will still die when it gets warmed up. I've found that the choke pull off wont hold a vacuum when I hook it up to a tester pump. Is this normal? and if not can this be causing my problem?

 

Which carb do you have? I might be wrong, but I think the choke diaphragm should hook up to a port on the carb. Is there a hose routing diagram under the hood?
john

 

Sounds like the pull-off is indeed bad, but it should only affect idle from cold to "just a little warm," that is, the engine will run overchoked and load up until it warms up enough that the choke thermostat opens a little. Wherever it hooks, I believe they all hook to "full time" vacuum.

 

According to the diagram a vacuum hose the runs from the underside of the air cleaner to a split that goes to the carb and the choke pull off. I believe its a holley 2bbl 1945 R40089. it will run ok when its cold but when it warms up it dies and will only stay running if I'm feeding it fuel. I've been looking for what the problem could be and so far the only thing I've been able to find is the bad choke pull off.

 

I would replace that choke pull off and also clean the carb on the choke plate shaft and the fast idle linkage. Hope that will work,if not you can always hook up a manual choke cable to it.

john