Ford 640 will not start

[1950drew]

I have a Ford 640 that will not start. Had low compression so I had the head reworked and new gaskets. Several shorts fixed. Starter turns great, new battery,new distributor, new coil, timing correct, plenty of fuel, carburetor set correctly (new carb). Anybody got any ideas?

 

[kb46852]

Did you do a compression test after the head was reworked?

 

[Turkeyfoot]

Pull a plug after you've been cranking it. If it's not trying to start then you should have gas on those plugs. Then check to make sure you have spark at the plugs, if you haven't done so already. If you're getting spark and gas, then look at your firing order. Make sure the rotor is hitting the number one contact on the distributor when that piston is at top dead on the compression stroke. Keep checking back here with latest findings. There's a lot of helpful people who will help you get it running.

 

[Tim PloughNman Daley]

I have a Ford 640 that will not start. Had low compression so I had the head reworked and new gaskets. Several shorts fixed. Starter turns great, new battery,new distributor, new coil, timing correct, plenty of fuel, carburetr set correctly (new carb). Anybody got any ideas?

6V or 12V? Why, why, why all the news parts??? Test the old ones? Rebuilding OEM parts always 1st option. Carb, distributor, GEN, STARTER etc. designed to be rebuilt over and over. New tend to be junk. Test the battery 1st? New doesn't mean good. Fuel Flow Test 2nd? What is a 're
worked head' and how does it correct low compression? Incorrect wiring is #1 root cause for non-starting. Buying and replacing all your parts willy-nilly without troubleshooting is a rookie/newbie mistake. You are just guessing. You ended up with the same problem even after all that so what does that tell you? Get the I&T F0-20 Manual and after fuel and batter test go thru entire wiring step by step and take no shortcuts.

Tim Daley (MI)

 

[Geo-TH,In]

I have a Ford 640 that will not start. Had low compression so I had the head reworked and new gaskets. Several shorts fixed. Starter turns great, new battery,new distributor, new coil, timing correct, plenty of fuel, carburetor set correctly (new carb). Anybody got any ideas?

I would suggest removing the breather tube from the carb and giving it a shot of starter fluid.
If it fires, you have a fuel problem.
If it doesn't fire you have an ignition problem.
That's a good place to start.

 

[old]

I have a Ford 640 that will not start. Had low compression so I had the head reworked and new gaskets. Several shorts fixed. Starter turns great, new battery,new distributor, new coil, timing correct, plenty of fuel, carburetor set correctly (new carb). Anybody got any ideas?

A lot of time when you rebuild the top of an engine you blow the bottom out due to only fixing it half way. I'll bet you still have low compression due to bad rings

 

[1950drew]

They had converted to 12 volt. The owner had worked on it. Had mutiple shorts in the wiring that I fixed. They were disconnecting the NEW battery to keep it from discharging. Still had the 6 volt resister in line with a 12 volt coil that had an internal resister. Removed the original. Dead shorts ruined the coil. The insulator on the distributor was missing and the wire from the coil to the points/condenser was burned in two so no spark. The head gasket was blown, thus low compression and water in the oil. Valve guides were worn out. Had valves ground and head shaved. Virtually no blow-by so rings seemed good. Compression is back to normal. Got timing correctly set, great spark, plenty of fuel and air. I even pulled the timing cover to see if a tooth had broken off on the cam or crank. I've only been doing this for 40 years. Guess I'm just too amateurist and need some help.

 

[used red MN]

Hello Drew, welcome to YT! After 40 years I would think you would now how to check cam timing by checking it at the “rock” position on number 4 cylinder valves, let’s not dwell on that. You are probably going to be a bit defensive on replies given here, only natural. Turkeyfoot and Geo have suggestions that sort of work together, if it fires on staring fluid you know the carb is your issue. Everyone can make a mistake, you say you been doing it 40 years that says something about your age, I am right there with you at 61. Some things just don’t come as quick and as certain as they once were. I will restate, are you sure that the distributor is timed on TDC compression and not exhaust? You for sure have checked the compression, set the valves after the head was installed an torqued? Plenty of fuel where? Need to see if it flows out of the carb drain plug. You can have a “garden hose flow” of gas at the carb fuel line connection but it has to get inside the carb bowl for the fuel circuits to be able to pick it up. Curious how you would explain a dead short ruining a coil? I suppose it may burned up due to a lot of ignition on time and the distributor side being grounded.