Ok so I have been working on 76 f150 with the 300 engine, single bbl carb for about a year now and have repainted the truck and redone the interior. During this time I didn't go through the engine as before I did all this work it ran great and didnt want to mess with a good thing.

Back in July I put the body back on the frame and started hooking up the everything back up and the truck fired right up even after sitting for over 6 months. I never really drove it during this time as I was slowly putting the interior back together.

In the last two weeks the truck will not start on its own. I have been just pouring a little fuel into the carb to get it started and then it would stay running on its own. There was a ticking noise in the distributor when the key was on but the engine not running. I thought it was the distributor going bad so I put a new one in and also replace the wires, cap, rotor and plugs. The noise didn't go away but the distributor seemed to have a lot of play so not to bummed about spending that money. I finally realized that the ticking was doing it with the pulses of the electric fuel pump. I saw I didn't have a ground between the motor and cab and I added one and the noise went away. However it did nothing to get the truck to start.

I messed around with the carb and the choke seemed to be working properly. I had a second carb and put that one on and still the same situation. Now when I try to start it with starting fluid it fires up but dies, however if I do it 2 or 3 times the truck will then run on its own and stay running, its like once I feel a little heat on the motor it will fire up. When I got it running the other day I let it run for a while and then checked the timing and it is where it should be. The truck runs smooth when it starts but I just cant get it started.

I don't know what to do from here, I am just stumped because a month ago I thought I was ready to start driving it again.

 

Do you have the chokes hooked up properly on the 2 carbs you tried? You've verified that you have spark at the appropriate instant.

How many PSI is your fuel pump putting out?

As a sample "choke" have a helper block almost all of the airhorn with their hand. See if that helps starting.

If none of this leads you to your problem, I might want to do a compression test on this engine. 6 months ago it was summer, and the parts of the engine were warm, and therefore bigger. This would seal the engine a little better. When you crank the engine over a few times, you create friction and then heat and you get the "summer" start, with heat and higher compression.