Hi guys. My67 Ford F100 (352) has been running fine but now and then hard to start. Would have to hold accelerator down to the floor and crank until it finally, grudgingly fires up.
Yesterday, 110 miles from home on a camping trip it stalled out and backfired going uphill. Started up but then on another bumpy uphill section it sputtered and died. Cranks but no start. 6 mile walk and a tow home at midnight.
History: Recently replaced plugs, wires, disto cap, points, condenser and coil in an attempt to fix the starting problem. Seemed better for awhile but then the starting issue came back. 3 months ago replaced two bent pushrods and lifters and rebuilt the carb. Its always had a little hesitation under gentle acceleration, like there was a dead spot right when you pull out especially when cold.
Today it started once but I had to pour gas in the carb. Then after I shut it down,no start. I see gas squirting in the carb. Tried pouring gas in the carb again but no start.
Any ideas?

 

First of all, ditch the points. They start degrading immediately upon installation.

If it acts flooded, then maybe it is. My 65 Mustang would barely start after a drive and it sitting for 10 minutes.. the problem was a pinhole on the accelerator pump diaphram which was draining the fuel in the bowl and down the intake.

Check your float level lately? What about choke setting?

 

I haven't checked the float level and I'm not sure about the condition of the diaphram. I can tell you that the choke doesn't help when it's struggling to start. It's a manual choke. The weird thing is that sometimes it will start up immediately and then it could sit for two hours and I'd struggle to get it started. I'm thinking that I will replace the fuel pump and see if that cures it. I should swap out the points. I did that on my son's mustang with the pertronix and that wasn't a big deal. Thanks for helping out!

 

Is it taking ill and catching the vapors? Summertime is hot weather

 

Not sure what kind of gas you are using but the ethanol can gum things up pretty quick. You might try some Seafoam as a quick fix. If you go fuel pump it might be god to use an electric one with a regulator. I'm no expert on fuel pumps but I am planning to switch at some point on mine.

 

What was it above 80 - 90 Deg. When it's real hot old cars will vapor lock . That's why all cars now have the fuel pump in the tank .

 

It was probably 80. But then yesterday, after it had sat all night it was cool and it still wouldn't start. What kind of pressure should I see from the pump? I'll see about getting a pressure gauge and check that.

 

Fuel pump pressure should be around 6psi if I remember right.

 

Just to be sure, put a jumper wire from the + battery to the + side of the coil when it acts up and see if that makes it start.

 

Sounds like to me that you may be running rich and your engine maybe carbon fouled. Pull the plugs and check them out. You might even check the timing and readjust the carb settings.

 

If I read it right it's not running now. Put the engine on #1 and see where the rotor is pointing. I've sheared the roll pin for the distributor gear on a couple of different engines.

 

OK, well I put a new fuel pump in today and no change. I checked the points and they were closed when they should have been open. Gapped them and it started right up. I put some seafoam through the carb and it seems to be running pretty well. I'm not convinced though that the points were the issue. I actually pulled the new fuel pump back off and put the old one on because the new one had some leaking fittings. At any rate, its running again. I guess I'll watch it for awhile and see how it goes. Thanks for the help. I knew I came to the right place.

 

Many of us recommend ditching the points for a pertronix kit. It's about $80, but it's one of the best things you can do to an old vehicle.

 

Yup on 351s post.

 

If you find it' still giving you troubles while going up s hill popping back through the carb. You may be having issues with the exh. valves seats. if your motor still has the stock unconverted heads for unleaded gas.

Then, I'd do a compression test to validate good or bad low compression in one or two cylinders.

Any more Backfiring or popping back through the carb could be causes by this..
Good ol cheap gas burn much hotter then the higher grade octane gas that causes the valve seats that start eroding under 3/4-to full acceleration will cause a flash back past the exh. seat causes by the red hot cinders of molten metal.

Orich