Ford 3000 starting problems

[skytracker]

I have a 67 Ford 3000 gasser that won't start. Ran great all winter even in -20 deg weather. Couple weeks ago put it in the barn after moving round bales. Week later tried to start it. It did but died before I got out of the barn. Seemed like not enough fuel getting thru. Rebuilt carb with CNH kit flushed fuel lines and pump screen. Now it tries to start but backfires thru carb. Has new plugs and cap and rotor. Could be timing or stuck valve.
Fuel appears all good. Hot spark too. Never had backfire thru carb before.
Have seen that on other engines. Any ideas sincerely appreciated.

 

[skytracker]

So far found diaprahm for vacuum adv had junk in it. Cleaned that out. Trying to see if I can scribe a line and move dist a little either way and see what I get.
Soundguy or other experts have this before??

 

[Ultradog MN]

You don't mention having done anything with your points and no mention of whether you have spark.

 

[skytracker]

I did say I had hot spark. Checked again all three cyl jump 1/2 inch. I no longer have points installed ignitor electronic ignition and coil. Had been running great with it.
Believe timing is slightly off but secondary. Went back to zero with the fuel. I have rebuilt several of these carbs over the years but could have missed something. I have good fuel to carb inlet and left screen there out.
Earlier replaced shutoff, cleaned sed filter, flushed lines. Carb initially good flow out the bottom plug but slows way down. Suspect float or needle but both are new. Pulled carb again last night. Float seems free and right at 63/64. Inlet needle is new and seems free. Not sure at all. Really need to be cleaning up fields with this.
Maybe float is contacting bowl and binding?? Put carb back in this am. Same issue tries hard to start then sometimes backfires out the carb.

 

[skytracker]

Elec ignition and coil have been in since 2012.

 

[Sawdustsmb]

Have you pulled the valve cover to see how the valves are moving?

 

[skytracker]

Thanks for the replies guys.
Did not check valves yet. I pulled the carb back out to double check the float and inlet.
May have a couple issues. But I believe the Holley is still a problem.
Trying to get a zenith for it. Might get to the valves tomorrow.

 

[skytracker]

Sorry, traveling for work. Tractor is running great now.
Had checked the valves and did not find anything it all looked pretty good. Timing was a bit off.
The carb float was catching the side, tweaked that and had good fuel coming in. But still would not start. Tore carb down again and new accelerator
pump was locking up must have some scoring inside pump bore. Ordered a zenith replacement. Replaced carb. Now it starts! Still slow to crank though.
Tweaked the timing now dead on and smooth running with great power. Slow crank went through all the checks, starter had extreme high resistance. Replaced it now starts and runs great. Carb was a bit pricey but seems worth it. Starter was warranty replacement from last year when the original finally quit. So $350 for carb and 60 for CNH rebuild kit trial, and plugs cap and rotor am into it for $450 but now she's good.

 

[Soundguy]

nothing like a zenith to turn a gasser ford 3 cyl into a worker from a badly wheezing barley able to start tractor. kinda pricey.. but worth it sometimes.

 

[skytracker]

It wasn't too bad before this episode. But what a difference now. Thanks for the reply Soundguy.