choke to run / vacume on tank

[Soundguy]

Here is a question that i asked in the vintage tractor forum, but will ask here also, incase readership doesn't cross down there.

I have a ford 8N, yesterday added some fuel stabilizer to 'winterize' the gas and then let the tractor run for about 20 minutes to let it circulate, etc ( changed coolant too ).
Anyway, she stalled out and would restart.. but needed choke to run, and then stalled again.. each time needing more choke to run. It was dark, so I didn't mess with it much.

Initial thought was a leak between the carb and manifold ( or manifold and head as someone pointed out ).. but it had never had this before.

Then I started thinking about the gas cap... I usually run it loose, as it is not a stock cap... but I put it on tight after the fuel additive... could this have pulled a vacume... thus making me choke it ( more vacume to carb).. to get it to run?

I won't be able to get out to test this idea untill wednesday afternoon, as my work is busy... but just wanted to have some ideas ready when i do go out.

thanks,
Soundguy

 

[Carl_NH]

The tight cap would create a vacuum in the tank esp since you run it loose w/o problems. Run it a gain for a few minutes turn it off then open the cap to hear an inrush of air. Alternately run until it starts to heistate open the cap should pinpoint the problem. I don't beleive the fuel stabilizer will cause this as I recall it's an alcohol or methanol based additive.

Carl

 

[bgott]

The alcohol or methanol in the fuel conditioner could have washed crap loose from the sides of the tank, plugging the screen on the fuel bowl. It also could have absorbed water out of the bottom of the tank, leaning out the fuel mixture.

 

[tiltbed]

Soundguy i think you hit the nail on the head.I have a locking cap on the ford. Don`t like to keep the local`s beaters goin if i have to leave it in the field over night.found out if i pushed it down two clicks it wouldn`t run very good....had to choke it a lot.pushed it down 1 click and ran just fine. Sid

 

[Soundguy]

I'll let everybody know what I find as soon as I can get tot he tractor and work on it. Might be tonight, or possibly friday morning.

later, and thanks,

Soundguy