If you've not checked/replaced the spark box coil, do so.
As I prolly mentioned before I had a similar problem with my 77 f250 4x4.
I replaced spark box, gave it a full tune-up by replacing the distributor, rotor, cap, wires, overhauled my motorcraft carburator, replaced all fuel lines (fully insulated), fuel pump, fuel filter, and my truck was still faulting after it reached a certain temp. So then I replaced the ignition coil and that fixed it for me.
She runs like a beaut
again good luck!
Mud

 

Heres the deal.....at least with my 73/302.

It will start fine cold. Cranks like is should. After it warms up to temp, it drags and doesnt want to start. It will start after the starter drags a couple turns.

I replaced the coil. No help. I marked the intake with the #1 plug wire locale on the cap and pulled the distributor. The rotor was off one notch advanced. I turned the oil pump shaft and set the distibutor back in right on the money. It ran smoother (go figure) but still no help.

I replaced the solenoid on the inner fender. Still no help. I pulled the battery cables and cleaned and checked those. Still no help.

Then to the starter. Remember, I didnt have this problem before I tore it apart and rebuilt.

I had the head mechanic look at it when I got off work today. I explained to him the problem and what I did so far.

He pulled the hood and took one look at the starter and said theres the problem. Its that Metric Starter (metric starter?). An Autozone special...... He said with the 2 tubes off the headers running that close to the starter that when the heat got to it it acts up. Cheap parts, cheap case, and cheap bendix. Cheap starter.....

He got in and cranked and starter several times in a row. Nope. Timing is fine. Starter......he went on to check the dwell and do a VET test type test. Nope. Everything is fine. Starter. I said, Ok Ok I get the picture.........

I dont buy anything that is a pain to replace from Autozone. Yeah, its got a warranty, but I got tire of burning starters, batteries, fuel pumps and alternators with big horse engines.....

I took the starter to a rebuild shop and exchanged it for a (normal) 45amp starter for $26. The rebuilder said normally he just charged a core charge of $15 to exchange, but he would not rebuild the one I brought in and threw it it the junk pile........ I did get a reseller discount though. Go figure?

I reset the timing by ear to where it started the best cold, started it and let it warm up and adjusted the timing by the way it ran and drove it to work.

I parked, shut it off and restarted......Problem solved After work, I drove home. Settin in the driveway, shut it off and restarted. yep! Problem solved.. It was a pain to trace out........

Junk Starter! It wasnt getting the heat from the headers with stock manifolds on it, so I didnt have the problem.........

 

We are constantly talking about installing heat shields for starters on trucks with headers.

This is no surprise to us.

I have never heard of a metric stsrter just those new smaller High Torque starters that are on the market.

The biggest problem with identifying the problem for some is....... people don't understand the different electrical type systems and how they MIGHT be inter-twined with another.
Ie: Starting system,Charging system,Ignition system.

I have heard things like : "The starter won't turn the engine over..someone there says.....maybe it's the alternator ? "

 

I have exactly the same symptoms. Starts great cold, runs beautifully, won't start when hot. I believe it is either a result of the starter getting hot from the exhaust (although im running stock manifolds) or the engine being too tight. (just rebuilt) If the engine is too tight, wht can i do?
-kit

 

Improper timing can also cause slow turning starters.

One other problem that can occur is that aftermarket ignition systems do not have the timing retard during start function in them. This can happen with aftermarket DuraSpark modules as well as aftermarket ignition systems. The advanced spark throws an additional strain on the starter causing it to turn the engine over slowly.

There are different windings in starters for different applications. The wrong type of starter even tho it "fits" can cause slow starting.

 

I pulled my 460 from a lincoln, so the starter is a lincoln. Could that be causing a problem?
-kit

 

probably not, unless the starter was not right in the Lincoln to start out with.
Pull the starter off and inspect the bushing for wear. Do a starter bench test and verify it spins freely. If the starter armature, bushings, windings, are contiminated with oil and grease, the starter will turn slow.

 

Are there any tags or numbers on that starter for part verification?

 

How many of you having this problem have your ground wire off your battery bolted to an aluminum intake?

My truck went down without warning yesterday. Shut it off, and it wont start back up.

I put another new starter in, a new solenoid, another cable and still nothing.\

I can wiggle the ground til the headlights come on, try and start it, and the headlights go back out.

I have a bad ground somewhere. Gotta find it.

 

Always bolt the ground to the block near or on the starter. A separate ground should go to the body and frame. The OEM cable had a tab for the body and frame grounds.

 

Every year, early in the on-set of warm weather, I have that exact same problem. That reminds me to re-lean out the idle mixture just a bit. ('75 360, original 2100 carb)

I have a big-ol' clunky 6 volt Bendix electric fuel pump in series with the fuel line, right after the tank switching valve. The switch to run it used-to-be the windshield-washer-motor switch and wire. (never really like windshield washers)

Anyway, I run that fuel pump until the carb's re-filled. I can tell by the sound of the pump running, when it's done filling the carb. Pretty much do that everytime before a start. Works like a champ!

Way back in the late 70's I knew a guy that claimed his Austin Marina started better than anything else because he let its electric fuel pump re-fill the carb before running the starter. A couple years later I bought a junk (6 volt) VW dune buggy that just happened have this old fuel pump on it...

Alvin in AZ

 

Im going to call this one "chasing the goose" because I feel as if that is what I am doing.

Maybe we are all looking for a problem with the "hot start" issue in the wrong place.

After chasing out all the timing and electrical, and then the truck going down on me without warning and replacing everything that made no difference, I am under the conclusion that all along it was the ground.

A bad ground can cause many problems.........

Actually, ground wires. Bad ones.

I had already replaced all the wires, but the grounds. They have been in the same place (on the intake) since I have had the truck, and have been replaced twice in 4 years as a precaution. The last set coming from (guess where)....Autozone.

I took the negative cable and one that I had replaced and welded them together to make it long enough to reach the starter bolt. Still the same problem.

I changed batteries out of my wifes car. Same deal.

Getting fed up, I put jumper cables on and placed the black cable on the head bolt, rather than the battery and it cranked right up.

I went and got a 4 gauge cable 56" long and replaced it. Cleaned the battery terminals again (yeah, again) and put the new cable on.

Ok, new starter (twice), all new cables (+ and -), new solenoid (twice), new battery, corrected the timing issue by one notch, and problem solved. The starter spins so fast I almost dont know it did. Its kinda an (rr varooom?) kind of thing. Instant fire and run.

I put the jumper cables on the starter I took out. Same thing there. Instant high speed crank.

Maybe my grounds were just barely holding on casuing the starter to drag when it was hot (hot cables) get weak and lose transmission of electric energy, especially if they are corroded, or not heavy enough guage.

I have driven it to and from work, and around town. Temp gauge is running cooler, oil pressure gauge is steady, lights are brighter, and it starts the same hot, as it does cold.

Maybe all was fine prior to the rebuild, but since the big horse rebuild it put more of a drain on the starting system, causing it to completely fail, rather than just work.

Maybe, hopefully, ( a few choice words here) I am done....."chasing the goose?"

 

We've always mentioned having a good ground.

Btw, it is always best to place the black booster cable on the engine somewhere and NOT the negative post of the battery.
sparks can ignite the battery gases and cause an explosion.

 

A meter would have told you exactly were that problem was!

Anybody and everybody that owns and maintains an older vehicle needs to get and learn how to use a volt-ohm meter.

It's not all that hard to learn and right here is as good of a place as any to learn it. I prefer the old analog meters for this sort of work but whatever floats your boat.

Are you game?

Alvin in AZ (retired RR signal maintainer)

 

So....... After the "goose chase" the question remains......

Was the problem with my truck the starter, the ground, or the timing????

The timing? Probably not, other than it missing a little and not running just right.

The starter? Probably not, other than not having a good ground.

The ground? More than likely? I didnt have the problem prior to the rebuild, so why would the problems start afterwards?

My theory is that since the rebuild there is twice the motor and twice the strain on the starting/electrical systems, especially the ground and that caused the ground failure. Maybe it was close to failure anyway and the rebuild finished it.

I'd say at any rate, the ground problem was contributing to the starter cranking slow when it was hot and since I had just rebuilt it thinking it was a timing problem.

The starter was 3 years old and probably wasnt in the best shape and that didnt help either.

It sure cranks really nicely now, whatever the cause hot, or cold. It starts the same. Hope this helps the rest of you guys one way or another.

David