Missourian
Diamond Member
In the parking lot at AutoZone.
Been chasing down that "heat soak starter" problem... replacing batteries and battery cables in my '89 F150... this was June of last year...
www.usmessageboard.com
And y'all likely saw my battery replacement thread. I was replacing everything from the battery to the starter that I thought may have been causing the problem... and that led be to break the starter solenoid (Starter Relay technically I recently learned). Took three replacements from AutoZone and an upgrade from Duralast Standard to Duralast Gold to get one that the plunger didn't hang up in and keep the starter engaged after the engine had started. You almost have to test every new part you buy anymore.
Anyway... thought I had it licked but the "heat soak" slow cranking without starting while hot persisted and was getting worse. Even on short trips of a couple miles the engine needed to cool.
So...I was at the parts store getting something... don't remember what... and when I went to leave... Crank but no start. Ether didn't even coax a cough or a sputter.
Did what I could without much by way of tools... but in the end a multimeter at AutoZone was a not that much cheaper than a tow and not nearly as nice as the one I already owned... so ignominiously towed out of the AutoZone parking lot and back to the house to be multimetered and test lighted and hopefully repaired.
No spark. Replaced the ignition coil on hunch. Bad hunch. No joy. No pulse from ICM to TACH side of the coil... just a bright, continuous 12v while cranking.
Back to the parts store for an ICM. Supposed to be removable with a 5.5 mm socket. NOPE. 5.5 mm THINWALL socket.
Back to the parts store for an Ignition Module Tool. A somewhat reasonable six bucks.
Got to turn the distributor to access the rear screw... so clean the base, mark it, loosen the bolt, turn it until the ICM touches the alternator bracket. I'll get a picture tomorrow, but this isn't an ordinary bracket... It's the granddaddy of all brackets. It holds the alternator and the smog pump and something else...a real chore to remove or even loosen.
The front screw is easy enough to remove, but I can't get on the rear screw because that silver knurled twisty part won't clear the thermostat housing.
Probably the easiest route is to drain the the radiator and remove the upper radiator hose and then the thermostat housing. Removing the distributor entirely or removing the bracket were other options... but I chose the option behind door number three.
I got out the Franken-bandsaw and cut the module tool in half.
WooHoo...now I can get on the screw head and remove the ICM by turning the half tool with an open end wrench.
Installed new ICM, realigned distributor and tightened her down...and presto... Truck starts and runs as close to like new as it did before... which is not very but good enough.
So... to make a long story even longer... I'm wondering if the ICM was causing the "heat soak" problem from the beginning... that it was failing slowly and when it got hot it was retarding the timing and causing the slow crank no start condition. Have to take it on a long drive, shut it off and see if it will start right back up.
Time will tell...
Anyhow...$50 for the tow, $42 for the coil, $45 for the ICM, $6 for the tool, roughly three hours of work, an hour of travel time total to and from the parts store three times and probably four hours of research to get her up and running.
Did I save money? Maybe... but probably not.
Did I learn a lot? Absolutely. Diagnostics of electronics is likely my weakest area in mechanicing.
Did the satisfaction of getting her running again make up for the frustration and hours of research? You betcha! When the truck started I threw my arms up like Rocky topping the stairs at the Philadelphia Museum of art... Literally... That happened.
A good day...
Been chasing down that "heat soak starter" problem... replacing batteries and battery cables in my '89 F150... this was June of last year...
Made a starter heat shield...
Old starter on the pickup had a heat sunk starting problem... Has had for years... But it started getting worse of late so I replaced the starter. Someone before me threw the heat shield away when they replaced the starter...but I figured the new starter would be ok for a few years. Nope...
www.usmessageboard.com
And y'all likely saw my battery replacement thread. I was replacing everything from the battery to the starter that I thought may have been causing the problem... and that led be to break the starter solenoid (Starter Relay technically I recently learned). Took three replacements from AutoZone and an upgrade from Duralast Standard to Duralast Gold to get one that the plunger didn't hang up in and keep the starter engaged after the engine had started. You almost have to test every new part you buy anymore.
Anyway... thought I had it licked but the "heat soak" slow cranking without starting while hot persisted and was getting worse. Even on short trips of a couple miles the engine needed to cool.
So...I was at the parts store getting something... don't remember what... and when I went to leave... Crank but no start. Ether didn't even coax a cough or a sputter.
Did what I could without much by way of tools... but in the end a multimeter at AutoZone was a not that much cheaper than a tow and not nearly as nice as the one I already owned... so ignominiously towed out of the AutoZone parking lot and back to the house to be multimetered and test lighted and hopefully repaired.
No spark. Replaced the ignition coil on hunch. Bad hunch. No joy. No pulse from ICM to TACH side of the coil... just a bright, continuous 12v while cranking.
Back to the parts store for an ICM. Supposed to be removable with a 5.5 mm socket. NOPE. 5.5 mm THINWALL socket.
Back to the parts store for an Ignition Module Tool. A somewhat reasonable six bucks.
Got to turn the distributor to access the rear screw... so clean the base, mark it, loosen the bolt, turn it until the ICM touches the alternator bracket. I'll get a picture tomorrow, but this isn't an ordinary bracket... It's the granddaddy of all brackets. It holds the alternator and the smog pump and something else...a real chore to remove or even loosen.
The front screw is easy enough to remove, but I can't get on the rear screw because that silver knurled twisty part won't clear the thermostat housing.
Probably the easiest route is to drain the the radiator and remove the upper radiator hose and then the thermostat housing. Removing the distributor entirely or removing the bracket were other options... but I chose the option behind door number three.
I got out the Franken-bandsaw and cut the module tool in half.
WooHoo...now I can get on the screw head and remove the ICM by turning the half tool with an open end wrench.
Installed new ICM, realigned distributor and tightened her down...and presto... Truck starts and runs as close to like new as it did before... which is not very but good enough.
So... to make a long story even longer... I'm wondering if the ICM was causing the "heat soak" problem from the beginning... that it was failing slowly and when it got hot it was retarding the timing and causing the slow crank no start condition. Have to take it on a long drive, shut it off and see if it will start right back up.
Time will tell...
Anyhow...$50 for the tow, $42 for the coil, $45 for the ICM, $6 for the tool, roughly three hours of work, an hour of travel time total to and from the parts store three times and probably four hours of research to get her up and running.
Did I save money? Maybe... but probably not.
Did I learn a lot? Absolutely. Diagnostics of electronics is likely my weakest area in mechanicing.
Did the satisfaction of getting her running again make up for the frustration and hours of research? You betcha! When the truck started I threw my arms up like Rocky topping the stairs at the Philadelphia Museum of art... Literally... That happened.
A good day...
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