Hey guys, Heres what i have,car starts fine cold but when it is real warm or excessivly warm outside sometimes she wont crank over, but only when real warm or hot, after it cools down it cranks fine every time. Been meaning to figure it out and never got around to it. Now, it doesnt want to crank at all. Is this a bad engine harness? Because this one feels pretty crispy hard. Is this where i start or can i check voltage coming in to starter.:(

OH, forgot to mention, it starts right up by crossing leads at starter.

Changing the Harness wouldn't hurt, but its possible that you need a better ground.

checked that and think its ok, Is there anything else besides ground or harness?

battery is fine

Next thing to check out would be the ignition switch.

Assuming the battery cables are clean and tight, it's a bad starter motor or solenoid!:yes::thumbsup:.....Most likely the solenoid!

Sounds like you aren't getting enough current to the solenoid. Get a Ford starter relay and install it like this:

http://home.comcast.net/~onovakind67/starterrelay.GIF

It's an easy fix, just a couple of 10-12 gauge wires and the relay. If your engine starts on a regular basis when hot you'll know that you have a connection problem in the circuit that powers the solenoid.

I'd check that you have enough available amperage to the starter if you are only having a problem with a hot engine. You could be having a hot soak problem with the starter also. Here is a good check list. The first check is "available battery voltage." For the starter to crank at normal speed, the battery must be at least 75% charged (12.4 volts or higher). Low battery voltage can not only affect the starter but every other electrical system in the vehicle.

A. Set your DVM to the 20 volt scale, then connect meter positive (+) lead to battery positive (+) post (not the clamp or cable), and the meter negative (-) lead to battery negative (-) post.

B. Disable the engine so it will not start when it is cranked. (Ground the ignition coil wire, or disable the ignition circuit or fuel pump relay.) Limit cranking time to 15 seconds or less.

C. While cranking the engine, record the volt reading on the DVM. D. Next, connect your meter positive (+) lead to the battery terminal stud on the starter, and the meter negative (-) lead to the starter housing.

E. While cranking the engine, record the volt reading.

F. Compare the two voltage readings. If both are the same, there are no excessive voltage drops on the positive feed side.

G. If available voltage at the starter is not within one (1) volt of battery voltage, there is excessive voltage drop in the circuit.

The next test is for voltage drop on the positive side of the starter circuit.

A. Make sure the battery is fully charged.

B. Disable ignition.

C. Set DVM on 2 volt scale.

D. Connect meter positive (+) lead to positive (+) battery post, and the meter negative (-) lead to the battery terminal stud on the starter. While cranking the engine, record the voltage reading.

The maximum allowable voltage drop including the solenoid or external relay in the starter circuit should be 0.6 volts or less.

If you find more than a 0.6 volt drop in the starter circuit, you can isolate the bad connection by using the following voltage drop tests.

* Check the positive battery post and cable connection by measuring the voltage drop between the two while cranking the engine. Connect the meter positive lead to the battery post and the meter negative lead to the cable clamp. A good post/cable connection should have zero voltage drop.

* Check the positive battery cable by measuring the voltage drop end to end while cranking the engine. Connect the meter positive lead to the clamp on the positive battery cable, and the meter negative lead to the end of the cable at the starter. Crank the engine and note the voltage reading. A good cable should have a voltage drop of 0.2 volts or less.

* To check the starter solenoid or relay connections, connect the meter positive lead to positive battery terminal on the solenoid or relay, and the meter negative lead to the starter motor terminal. Crank the engine and note the reading. A good connection should have a voltage drop of 0.2 volts or less.

Next, you need to check the negative side of the starter circuit. To check the entire circuit, connect the meter positive lead to a clean spot on the starter motor case and the meter negative lead to the negative battery post. Crank the engine and note the reading. The voltage drop on the negative side should be 0.3 volts or less.

If the voltage drop is too high, set your DVM to the 2 volt scale and start checking each connection on the negative side to find the bad connection or cable. Use the DVM leads to check across each connection while cranking the engine as before.

Check the negative battery post/ground cable connection (should be zero voltage drop).

Check the negative ground cable from the battery to the engine (should be 0.2 volts or less).

Check between the negative battery post and starter housing (should be 0.3 volts or less).

Check between the engine block and starter housing (should be 0.10 volts or less).


The idea of using a Ford style solonoid is a good one. Also a battery with low cranking amps will cause your problem.

Thanks for the tips Ill check it out

1ga. Battery cables and a good gear reduction mini-starter and you'll never deal with it again.

I just put a Tilton super starter on my 69 and love it had same problem with stock GM starter $300 dollars but I think its worth not having the aggravation.