Packard Forum Index » Pre-War (1899-1942)

My 39 120 is finally running well, and since most of the glaciers have melted here, I was able to take it out for a ten mile run. So far so good, until I stopped at the hardware store for a few minutes. Tried to start the car, but it sounded like the battery was dead (one year old). Fortunately, the car was on a slope, so I was able to roll it backwards and pop the clutch to start it. Tried this several times more, with the same results. Easy starting when the engine is cold, but slow turning and usually no luck on starting it when the engine is hot/warm.

On checking out the starter, found that it was pulling 300 amps while trying to start the car when it was warm. (I think 250 is normal) I pulled the starter and swapped it out for another Autolite starter that has been sitting on my shelf for 15 years. It worked fine, and seems to have cured the starting issue.

Upon checking the suspect starter, I noted that the bendix drive was not pulling back. I suspect that the gear was staying engaged, causing the starter to spin while driving. Which probably made the brushes wear out quickly. I'm not much of an expert on starters, but this did seem to make a difference. The starter I put in is an Autolite MOL 6003 8D, and the one I pulled out is a Autolite MAW 4024.

Any feedback from the experts would be appreciated.

I would be very surprised if the starter would be staying engaged while the engine is running. The over revving would be severe and you should hear quite a bit of noise if the starter lasted very long. The photo shows what Packard said could happen if the over running clutch (Bendix) should stay engaged.

Which (if either) is the correct starter for the car? I'd be curious if there is any specified torque difference between the two starters. With a hot engine, anything marginal in the cables, connections, battery condition, friction in engine, etc could be the tipping point if the problem starter is barely adequate to start with.

I also seem to remember a thread where hard starting when warm was traced to timing being slightly advanced. IIRC, problem was alleviated by moving it back a touch.

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I would guess that more than likely you just have a tired starter. The reason the drive was still engaged is because that style of starter drive does not dis-engage until the motor starts and exceeds the RPM of the starter. I'm guessing by your description of events that the last time you tried to start the car with the faulty starter, it did not start and therefore the drive would not have dis-engaged.

The picture HH56 provided is a very accurate description of what does in fact happen if a starter stays engaged after the engine starts.

-Jason

Finally found the problem now that I'm off from a 3 week vacation. Took the starter to the generator shop today and they called me back about an hour later. When I bought the car, it had been converted to 12 volts. Someone had had the starter modified to have 12 volt windings, rather than 6 volt. I converted the car back to 6 volts when I rewired it last winter. So the starter worked ok when the engine was cold, but when it was hot, there was a bit more resistance and it just didn't spin fast enough. So if anyone out there has converted a 38-40 120 to 12 volts, I can help you out with a nice 12 volt starter motor. I will post photos of it tomorrow; I think it is a AutoLite.