Hi, I'm looking for possible solutions: 67 coronet 383 2bl, auto, point distrbutor, car runs great, accelerates good and does not ping or run on after being shut off. factory heat guage within spec and does not boil over when shut off. starts great when cold but barley turnes over after driving 25 miles.When I say barley turnes over I mean perhaps 1/2 a crank and the battery sounds dead, yes it has started, but somethings not kosher. any comments will be appreciated....thanks...ps....I just went out after letting it cool down (45 minutes) and the car starts great

heat soak in the starter. battery internal cell going bad. cables/terminals need cleaning. eng friction sky high when hot. In order: easy to sub in a known good batt then clean (all large)cables from post to post then check turning torque w 1&1/4" socket/breaker bar when hot then another starter

Thanks, but why would the car start great after 45 minutes of cool down if 1. bad connections, 2. battery cell bad? and I don't understand what the 1 1/8 socket would do? . what would cause sky high friction?

Use the 1 1/4" socket and breaker bar or 1/2" drive ratchet on the crankshaft bolt to turn the engine over cold then try it again after it's hot to see what the difference is. It shouldn't be very much harder to turn over hot. Make sure the key is out of the ignition. If it isn't any harder to turn then you know it's not the engine causing your problem.

Thanks, Suppose the engine DOES turn over harder when hot. What would be the cause?. This motor has been rebuilt.

Forged pistons and not enough clearance???

I have no idea what was done to this engine, it was rebuilt in 1991 and has been driven appr 10K miles and i would have thought any major problems would have been taken care of.

Make a heat shield for the starter out of a piece of thin metal, i used a piece of stovepipe back in the day. If the previous owner installed a heavy duty starter they are longer and sit closer to the manifold therefore they get hotter.

Check the timing, may be too far advanced causing hard start when warm.

CLAMP ON AMP PROBE
I've used them on 240-440 phase AC motors and starter relays but never used one on 12v DC.
But if you have a probe, clamp it over the battery to starter cable and watch it as the engine heats up. If the AMP reading changes as the motor heats up, it's either the starter or cable or both.

http://www.sears.com/shc/s/p_10153_12605...00001&aff=Y

I had the same problem, turned out to be the voltage regulator was junk. Amp gauge didn't show anything out of the ordinary(which isn't much to begin with). I guess it was either not charging or just barely charging. It would start up fine when cold, but give me nothing when hot. New v-reg and problem solved.

My 70 Charger has similar symptoms. When cold or after a reasonable cool down, it spins over fine. A warm restart gives me slow cranking. I have about 4000 miles on the rebuild. I have tried different batteries, starters and even a heavy 2 guage ground strap with ZERO difference. I was thinking that the thermal expansion of the pistons could be to blame as well. I file fitted the rings to .022 like I was instructed and the piston to wall clearance was supposed to be .005. I had the heads off last year trying to fix a smoking problem and every cylinder looked great...No signs of grooves or scuffing. So what the heck?[

Vacuum advance hooked up to wrong port on carburetor.

I went back over the receipts I got with the car and there is a pattern, They replaced 4 starters, over the course of 10 years, it does show that the problem existed for awhile.As far as bad voltage regulator, the battery is charging because when it cools down it cranks and starts fine. 2. wrong vacumn advance hook up?, its a 2bl carb, can only hook up to one port? any more thoughts?..thanks again

I always run an extra earth battery size cable from the engine to the subframe and remove any paint from in between all earth points.

As 52 Savoy mentioned above, check the battery cables and starter for excessive resistance.

Take a look at this old thread on moparts:

Slow Cranking cold and especially hot

Hope this helps - good luck.

Thanks for the read, his problem was slow cranking when cold, my engine turns over normal when cold, but it is food for thought...

thank-you, any chance it might be the starter relay on the firewall?