[josimite]

Anybody ! Starting system checks out perfect electrically hot or cold. Can hear solenoid banging in but no start. Engine does not turn over. Apparently, jack shaft does not move far enough to energize starter motor coil. This problem occurs after parking the fully warmed up bike for more than 5 min. It can take an hour (usually more) to cool off enough to start. The bike will start with a push. I replaced the jack shaft last September and the hot start problem went away for 2500 miles. But it is back this spring. Fuel system is okay too. Runs great. Anyone out there run across this problem???

 

[HIPPO]

You say that you hear the solenoid banging in. You did not say that you hear the starter spinning without engaging the ring gear.

Probably needs one of those solenoid rebuild kits (dirt cheap) or you can disassemble the solenoid and buff the big washer and the contacts with a Dremel tool.
Make sure you check both the pull and the hold coils for the solenoid for open and short to ground, procedure is in the FM.

Make sure the battery cables are not broken internally.

 

[josimite]

Hippo - thanks for the reply! I'll look into the solenoid rebuild kit.

The starter does not spin under the hot start condition. Nothing spins. Solenoid holds in until starter button is released. I put a ammeter on the negative cable and pressed the starter button. It was pulling 175 amps +/- a few. That tells me the main contacts are allowing the current to flow but the rotor won't turn. That's what led me to check and replace the jack shaft. Perhaps I should have replaced the whole jack shaft assembly. A couple of times, I tapped the starter button rapidly umpteen times and got it to start.

With a fully charged battery I did starting circuit checks using the voltage drop method in the HD manual with no bad readings.

Thanks again for the info.

Josimite

 

[HIPPO]

If it draws 175A and doesn't turn, something is locking up, if you are certain the jackshaft does not engage the ring gear, then the armature itself is binding.

 

[HIPPO]

You might be able to remove the derby cover and see if the starter attempts to turn the engine.

 

[josimite]

Solution to hot start problem.



Hippo - It took a while to find this one. The solution was removing an extra retaining ring located inside the starter-to-jackshaft splined coupling on the jackshaft side! I can only assume that the damn thing had been in there since HD built the bike! There was one retaining ring in the grove inside the coupling. The second one was inside the i.d. of the splines and able to move around. I suspect that when the ear(s) of the loose retaining ring went between the ears of the retaining ring in the groove that it caused enough hot mis-alignment and would not let anything turn. It has not failed a hot start in 500 miles of St. Louis driving in 95 degree summer heat!

Thanks for the help last April!

 

[HIPPO]

Glad you found it. Strange things happen, it's a Harley. This sort of thing can throw anyone for a loop, all you can do is systematically tear the logical things down.