Howdy, she's a 77 F250 Ranger with 351M engine.

I have owned this truck for several years, but have only just insured her and begun to drive her, fresh oil & filter, greased ball joints, etc.

Today I drove a little further than usual, about 10 miles, and she would not restart. After she was towed back to my place, she started again, and ran fine.

It seems, therefore, that she may have a problem starting when she's fully warm. Is this common ? Any ideas or recommendations would be much appreciated.

I just fixed another problem. I will state it for completeness. I don't think it's directly related, but perhaps indirectly ? A previous owner converted this truck to electric fuel pump. Previously, the pump frequently refused to operate, or even die while the truck was being driven. I was stranded several times. The live wire to the pump was run from the coil's ignition wire. When I measured the voltage at this wire, with ignition on, it was only 6.4v. I removed this wire, and ran a new wire from the fuse box to the fuel pump. The fuel pump now always runs whenever the ignition is switched on. I mean, I have hos no more problems getting the pump to operate. But why the low voltage on the ignition wire ? Volts across the battery are more than 12v.

When the truck broke down today, I removed the output hose from the fuel pump while ignition was switched on. Fuel gushed out, so I am certain that the fuel pump and filter are OK.

Thank you

Stark

 

What does it sound like when it won't start?

There are a few possiblilities. Could be your starter is going bad from heat exposure. Could be initial timing too far advanced. Could be vapor locking and boiling fuel out of the bowls. Ignition control module could also be going out.

So some things to check:
First, check all cables and grounds for good contact and no corrosion.

The next time you're in a no-start situation, connect a test light from the TACH TEST (negative) terminal of the coil, to clean unpainted metal on the engine (ground). Keep the coil connected for this test. Hop in the cab and crank the engine with the key, the light should BLINK. This will rule out the ignition control module. If there is what looks like goo coming out from the bottom of the ICM then it's toast.

Also verify there is fuel in the bowls and it hasn't evaporated out. If it is vapor locking then you need a phenolic spacer to reduce heat transfer to the carb. Also check that your fuel lines aren't running right next to anything hot.

If you are experiencing starter kickback then you have too much advance. What is your timing at? If your timing is on, and the starter is still sluggish then it's time to find a new starter. Not a crappy remanufactured one, a new one. The reman are known to be junk.


Also hemichrysler....SOHC>Hemi

 

When it doesn't start does it crank over at all? Is the battery and charging system good? or does it Crank really hard like every time a cylinder hits compression it stops it?(advanced timing) Or does it crank good and fast, but doesn't fire up, like it's flooded? maybe try holding it to the floor when your cranking....Maybe it's the fire your not getting?? I've had that before. The coil must've been wiring up straight so it was getting too much voltage, and heated up and failed. but you let it cool for even 5 minutes, you were all set!! Pull a wire and check for the spark.

Also is your pump down by the tank? I've found that pumps definetely work better as close to the tank as possible. I'm sure fixing the wiring made it much better, but I've found location matters a little too. I perfer mechanical pumps with carb'd motors...Always. I've never had a problem with one. I've found them to be extremely reliable.

That ignition wire alot of times will have less voltage on a Ford because its a resistor wire. I've made my own wiring before and used a chrysler 1.5 ohm ignition resistor to compensate for that. But when you are on Start, I made it bypass the resistor for better spark when cranking.

 

I've had this problem before with my '76 F250. My issue was that the started simply got hot. I would dump snow on it, wait for it to melt off, and it would work just fine. I never tried a heat shield because my dad told me he already had. Didn't get a chance to try it myself, since I sold the truck before summer.

 

I forgot all about the Hot starter thing. The 466 truck has big 1 7/8 headers on it and has a small gear reduction starter, with heat wrap stuff and it works great! It's the only way a starter will last down there. I've also had my starter soleniod be the cause....does your soleniod on the fender get really hot? Luckily I moved mine under the dash on the '62 so I could see the sparks that's the only way I figured that one out!

 

Guys, thank you so much for the advice.

The fuel pump is located on the left side of the frame, in the vicinity of the driver's door. The truck has 2 tanks, both connected through same pump.

I neglected to write about what happens when starting fails. The starter motor cranks the engine with authority and conviction. I installed a heavy duty marine battery to ensure it.

The truck has 77,711 miles, and the coil appears to be original.

I'm thinking either coil itself, or vapour lock.

The route of the fuel pipe does take it in front of the engine, but I think this is normal. It does not stray close to the exhaust manifolds.

I will start with the coil.

'hemichrysler' is reference to my 58 Chrysler 300D with 392 Hemi.

I like Chrysler/MoPar cars and Ford trucks : 63 F750 flat bed, 77 F250 super cab long bed, 92 Ranger flat bed, 96 Ranger daily driver. Also a 69 International Loadstar dumping flat bed.

 

Just remember to think simple. old motors only need 2 things to at least run a little......Spark and Fuel. They are VERY easy to check for on the side of the road

 

Sounds like the ignition control module, overheats and shuts down, won't restart, cools off and truck fires right up.

 

No worries, I'm just bustin your chops a little. lol I like the old Mopars as well.

Run some tests before you start throwing money and parts at it. You don't want to buy a ton of parts only to find that a wire is loose. Know what I mean.