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Discussion Starter #1
So, after running new ground and hot cables of significant size, new battery as of 3 days ago and anything else I can think of, I still have slow cranking when the engine is hot. It will start, eventually. Cold starts are just fine.

With a bent timing indicator, I cant be 100% sure of what the base timing is. I know that this is a part of the issue, HOWEVER, set to wherever it is (As near as I can guess, it's probably around 5-6*) it seems to have great pep and no pinging. Retarding the static timing any results in the thing really feeling like a dog when pulling away from a light, but hot starts are fine.

Now, my thoughts are...since the timing is so fun and peppy right now, why not keep it that way, if I can simply slip one of the newer 460 starters in there and overcome the timing issue, everything should be dandy.

Am I overlooking anything here?
 

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You are talking about a Duraspark II Ignition, correct?


Are you using the correct Starter Relay and is it wired correctly?


In other words, are you using the "I" terminal to bypass the ballast resistor to the coil when starting, sending a temporary 12v for full starting power, which is then reverted to 7v-8v (reduced by the resistor) for normal engine running after starting?





 

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are you running headers?

how old is the starter?
 

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So, after running new ground and hot cables of significant size, new battery as of 3 days ago and anything else I can think of, I still have slow cranking when the engine is hot. It will start, eventually. Cold starts are just fine.
IF you had written this statement like this, you would know the problem in a heartbeat.

I still have slow cranking when the starter is hot.

When they get old, they build resistance, when they get hot they build more resistance. Sounds like it is time to put in a new starter.
 

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Discussion Starter #5
are you running headers?

how old is the starter?
No headers and the starter is probably 12 years old. Been sitting doing nothing for probably 9 of those years.

Guess I never considered high resistance in the starter.

Sweet. I'll get one as soon as I have a free day and I bet that solves my problem!
 

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yo,
Take it to a parts store for a free starting & charging sys check; such as most NAPA stores; "...Free Alternator, Starter, Battery, and charging system testing"

o DIY for the most part;
bad battery,
corroded cables and corrosion within terminal/connector betwee wire strands
or a bad starter motor.
A bad battery will be detected by a low voltage at the battery terminals (not the cables) while cranking. Corroded cable connections will be detected by low voltage at the cable ends.
A bad starter motor will draw a high current and the battery cables will get warm to the touch.
While it's cranking measure the voltages across the battery terminals. It should be somewhere around 12 volts or just below. If it is much lower than that, say 10 volts, then the battery is bad and should be replaced. If it is around 12 volts then leave the negative voltmeter lead on the battery and probe the starter. The voltage there should be 12 volts or so, not much lower.

If it still hasn't started and the battery runs down again then feel the cables to the starter, are they hot?
As my Bro-in-Grease and Parts Joe mentioned;

If so then the starter motor may be shot and is drawing too much current. If you can get a clamp-on ammeter then use it to measure the current draw of the starter motor. 300 amps is typical - 400 means that the armature is dragging on the stator and drawing too much current.
I think you probably still have the Durapark ignition in there?
Wiring Diagram by Seabronc
 

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My bronco was kinda slow cranking compared to my other vehicles for the first few years that we had it. I figured... "that's just the way they are, maybe it's a high compression engine?" One day, with a relatively new battery (1 year old and fully charged), clean cables and grounds, and even with an extra ground, and a jump, it wouldn't crank. Pulled the starter, and it spun on the ground, but I was sure that had to be the issue.

I took it to AZ where I knew they would test it. Unfortunately they don't test it under load, but just put it under cover and spin it. It was a little noisey, but tested fine. I replaced it none-the-less. Now the engine cranks up just as quickly as all my newer cars do. Aparrantly that starter was on its last legs for a few years, and we didn't know it.


Its funny that you are getting suggestions for two completely different issues. That's because of the fact that many people use the term "crank" when they mean "start"
Seattle is thinking that you mean "start" and gave you info in that direction.
Miesk5 isn't sure, and gave you info in both directions
And I'm thinking that you know the difference and think you mean "crank"
I agree with miesk5 that if you could see how many amps the starter is pulling, that would be the best way to test the starter, but I am willing to bet that you don't have an amp meter capable of testing that many amps. I know that I don't.
 

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I just had this same issue, my engine has cranked slow since I bought it.

Today I go to get a couple of new U joints, just to have incase.
Come out to start the truck and it cranked really slow, slower than normal.
Figured since I had just read this and I have a new battery and cables must be the starter.

Sure as sh!t, put a new starter in and it cranks and starts like it should!

Did it right in the parking lot, what are the odds that the starter would finally fail while I am at a parts store?????
 

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Discussion Starter #9
Turned out to be the starter getting tired.

A new gear reduction unit (Which weighs less than the stock, 45lb unit...) from Rock Auto set me straight.

Those geared units sure sound weird when they run...
 
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