non-starting problem

[rja]

when the car gets hot, the starter fails to work. this is after a 'heat-soak' time period, and when it cools down it starts again. the car has 12.5v at the solenoid wire when the engine is hot, but the solenoid won't energize. brown wire fix done; when you try to start, the headlights don't dim, but the oil press lite and the alt lite do. is the solenoid breaking down when hot, and not the starter? questions welcome, answers, too .

[So Cal Mark]

attach your voltmeter to the bottom post of the solenoid to see how much voltage is actually getting to the motor through the solenoid. Worn bushings and field windings can cause slow cranking when hot

[rja]

thanx for posting, mark. this is a NO start problem, not a slow start problem. i have connected a switched 12v circuit w/a momentary switch from the fusebox to downstream of the last elec connection going to the solenoid. this has proved fairly reliable in starting the car, as when i purchased it, the key switch wouldn't start it. turn the key to on, pull on the toggle switch and off you go. this circuit shows battery voltage when key is switched on, and when running (disconnected from the solenoid) shows about 14v (alt output). when hot, all bets are off. i'm thinking that the solenoid is dropping out when hot, as i get no action at all. when the starter turns, it sounds strong, and thanx to the dual points, doesn't have to turn long. next time the car is hot and won't restart, i'll check voltage thru the solenoid to see what it shows.

[azruss]

Sounds like the plate in the solenoid is not making good contact between the 2 lugs. This can be from a dirty plate or insufficient pressure from bendix drive actuator arm.

[rja]

thanx for posting-just seems to happen when it's hot. you can kill it after a run and it'll start right back up. but wait 10 mins and it's a no-go. car has 35k miles and leaks no oil. starter looks clean and i'll bet it's original. it's probably gonna come out; embarrassing when you go to leave a clients house and it won't start.

[So Cal Mark]

re-read my post. You need to put your voltmeter lead on the lower solenoid post, the one that has the lead into the starter motor. That will tell you if the voltage is going through the solenoid

[rja]

that's precisely what i'll do. thank you, sir.