On Wed, 13 Feb 2013 17:44:23 +0700, John B.
wrote:

On 13 Feb 2013 04:48:19 -0400, Mike Spencer
wrote:


May I highjack this, since Gunner seems to have hit on a fix?

I have an '87 F-250 that won't start when it's hot. Let it sit days,
weeks, even months, indoors or out, and it fires right up. Even when
it's near 0F. Run it for a few minutes and it'll start again.

But run it until it get thoroughly warmed up, shut it off, and it
behaves as if it had a nearly dead battery: a-WUMP a-WUMP a-wump aaaa
clickety-click. Let it sit for 10 to 20 minutes (depending on the
outdoor temp) and it fires right up again. PITA at gas stations.

Engine is a replacement, the smaller-than-original V-8 (I forget the
name/displacement) so the truck is a bit underpowered but starts and
runs fine except for this not-when-hot thing. I'm a former mechanic,
I've taken it to a guy who's good, we feel like we've tried and/or
replaced everything.

Know any magic tweaks or arcane bits of Ford lore that might help me?

When I was a kid I had a Chevvy that did sort of the same thing. It
turned out to be the ignition coil.


Impossible. The ignition coil will not prevent the starter from
cranking. It will make it not START, but not what the OP described.