hot engine won't start

[60apache4]

I have a couple questions about my 71 1-ton with a BB-402.

The engine won't start when it is hot so I replaced the engine wiring harness, starter, battery and ignition switch and it still does the same thing.

On the engine harness, what is the yellow wire for? When I hook it up as shown in the service manual and assembly manual the engine will crank and turn over but then shuts down. I disconnected it and it works fine, so I am thinking it is not used...Also, what is the heavy gauge pink wire for; I can't find it in the manual and my original harness didn't have one.

Also, I think I need a heat shield for the starter, so what are you guys with Big blocks running to shield the starter solenoid from the exhaust manifolds?

Thanks for your help.

[dwaite72lnghrn]

From the factory they had a stainless shield on the selonoid and around the starter halfway. Yellow wire should have been the starter to coil wire for full volts/amps at start. Not sure of your replacement harness or where your pink wire is but on stock harness pink is from the ignition switch and is a resistor wire to splice for coil power when running about 9.6-10.6 volts.
Sounded like heat soak on starter, Check for exhaust leak around starter, Normally it is a bad starter. Heat soak is where the starter/selonoid get hot and bind when you try and start. Just a click no turn or very slow turn. I will try and get a picture of my heat sheild but my engine is buried now so it might be awhile.

[69gmcbigblock]

Originally Posted by 60apache4

Also, I think I need a heat shield for the starter, so what are you guys with Big blocks running to shield the starter solenoid from the exhaust manifolds?

i had a similar problem on mine, but i had replaced the starter already, then got a fat leak on my header so now the new starter is already screwed up. i'm going to make a heat sheild if i can't find one, even without the leak it was getting too hot. i figured it can't hurt to add one.

[jhow66]

Here what you need to fix your problem:
http://www.madelectrical.com/catalog/st-1.shtml

Do you have points or HEI? Yellow you don't need if HEI. Pink wire goes to "BAT" on HEI.

(by the way I make my own "kit" for alot less) see below

[VetteVet]

Great job Jhow. I was wondering how they activate the solenoid in the kit from Mad electric. The newer trucks have the secondary wiring pickups located on the starter post so they would have to relocate them to a hot terminal, perhaps the battery cable side of the remote solenoid would work.
Here is another alternative I found that would work with the existing wiring.

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[jhow66]

Hey 'vet how come your diagrams looks so much neater then mine. You are right about the feed wires that sometimes are fed off the big starter post-forgot to mention to bring them up to the hot side of Ford solenoid. Also with it triggered this way there is nothing hot at starter until you start engine.

[60apache4]

Thanks everyone - thats exactly what I was looking for. Perhaps this should go the FAQs as it is a common problem...

My first consideration was a heat shield and then a Ford type solenoid setup too. Sometimes you can hear the ignition click and sometimes the starter drive will engage but then nothing. Now my stupid truck won't start at all even when I short the terminals on the solenoid. Perhaps there is something else electrical that is wrong such as some relay or fuse I couldn't think of.

[VetteVet]

Your last post begs the question, will the truck engine turn over and not start or will it not even turn over. If it won't turn over even when you short the starter terminals then you have a bad solenoid or starter. The short between the s terminal and the large terminal on the solenoid is the end of the line and the starter solenoid should engage and you should hear a loud click. If it doesn't turn over then the starter is bad. This is considering that the positive wire from the battery is making a good connection on the starter and the battery terminal, the battery is fully charged and that the engine and battery negative have a good ground.
I PMd Krue and he is considering putting the thread in the FAQS

[justplainjoe]

Heat kills, I'd check the connections from the battery to the starter, make sure the cables are not corroded. Grab them and give a good pull and wiggle, I've seen them corrode from the inside out and all of the above post. Heat from the exhaust really stiffles starter operation. Good luck with it.

[Rdub]

Any particular years/models for the Ford solenoid or will any remote Ford solenoid work?

[jhow66]

Originally Posted by Rdub

Any particular years/models for the Ford solenoid or will any remote Ford solenoid work?

All are the same-Jeep<GMC<Ford <AMC etc. (read this)
http://www.oldengine.org/unfaq/solenoid.htm

[special-K]

A heat-soaked starter won`t crank,sometimes,even when jump-starting off another vehicle.It`s just bound up,nothing electrical.I got through a hole summer by carrying a water cooler or a few water bottles to dump on the starter and header to cool it.I`d pull up,pop the hood to allow heat to escape,do my business,get in and try to start(mine wouldn`t even click.Just the warning lights would glow),no start,pour water on,close hood,start and go.The starter lasted all summer/thousands of miles.Sometimes you gotta do what ya gotta do.

[prostreet1967]

auto zone part number f475 f476 both will work