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hard starting when hot..fine when cold, suggestions?

3305 Views 10 Replies 10 Participants Last post by  wrenchturner
A friend of mine has a '70 Pontiac with a 406, he did away with the points and installed a Protronix module in the distributor. When the timing is high enough to run well (with no ping)its hard to start when it's hot. It starts and runs fine when cold. When it's hot it doesn't want to turn over like as if the timing is way advanced. If he backs down the timing, the problem is not as bad. If he leaves it retarded to start well, it doesn't have the power that it should. Any suggestions? Thanks HotRod
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Just a guess but what about a higher cca rated battery and some heavy gauge cables. Had an old Chevy once actually had two batteries in her.
Try a starter heat shield. Chevy's are well known for cooking the starter, particularly with headers. The problem is the solenoid is mounted directly to the starter and when hot has a very high resistance value.
Give me a little clarification, and I will help you if I can. When you say the engine is hard to start when hot, do you mean the engine is slow to turn over, or the engine turns over fine, and the engine is slow to start???
you could try a ford solenoid,summit or any other such place sells a kit to do this. it mounts the solenoid on the fender well away from the heat. I put one on my Chevy big block and never had any more starting trouble.I think the kit is less then $25.
42 Ford Guy is right
I added a Painless "hot shot" which is similar idea to Ford solenoid.
added the BUMP start option and I use it when tuning.

Chevy Starter won't turn when it's hot. design flaw?
lots of GM owners hate it.

Big wires, good cables, juiced battery... and a good tune.
We used to run lotsa advance for the pop, just dealt with the starter and wiring as needed.
I would check to see that the advance is working properly. If that is ok, maybe a high torque starter may solve the problem.
yes i have that problem to. as has been said it maybe a combination of a hot starter motor and/or too much initial advance and not enough machanical advance.I'm not familiar with the Protronix module but if it has machanical advance i would go for less initial timeing and more machanical. i have 14 deg initial timeing and around the same machanical 28 deg when it should be about 34-36 ish,(350 sbc)im planing a motor change soon so i'll wait till then to get my centrafugel weights(machanical advance) right but it starts fine when cold but not when hot.sometimes i have to retard it when its hot just to start it ,i also have headers that go so close to my starter you would think the two are in love.hope you have some luck with the problem.
Let me give a little more clarification. The car still has stock exhaust manifolds, no headers, so I would think that heat on the starter is not a factor. He is running about 8 degrees initial timing which should be plenty low enough. The motor a has slightly over stock cam, nothing radical at all. The best description would be as if you way advanced the timing and tried to start it. My thought is something to do with the electronic ignition. I know if you convert a small engine from points to what they call an "Atom module", it tends to want to kick back once in a while. The bigger cables may be an idea too. HotRod
bigger cables and battery are always a plus in any application, I'm wonderin if ya'll have considered a gear reduction starter similar to a factory Chrysler. I know that they are avalable for Chevy applications, aftermarket. I would check any magazine that is GM friendly for a source. just a thought

[ April 15, 2002: Message edited by: critter ]</p>
my opion would be the starter and a good ground a extra ground strap just a thought good luck drive by day and fly by night :eek:
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