Yesterday, one of my buddies got a new 1922 Center Door. I spent some time teaching him how to drive it. Of course, he stalled it out several times while learning to drive it. After a few times, the starter got cranky and wouldn’t work. He has what we all seem to refer to as a “dead spot.” It would only turn over when I tapped on the end of the starter.
As my son and I were working on rebuilding our starter this evening for our new/old Touring rebuild, I began to wonder why the starter gets a dead spot.
Question 1: why do they get a dead spot?
Question 2: if you replace all of the parts that typically come in the “starter rebuild kit” sold by the vendors, will that solve the “dead spot,” or is the dead spot something more complicated and sinister?
Question 3: if the starter rebuild kit won’t cure a dead spot, how do you fix the problem with the dead spot?
I would be interested in hearing what others would have to say on this too.
If it truly is a dead spot, as in turning it a bit will get it to "catch", then you probably have worn out brushes.
However, whacking it to get it to go, tells me that the terminal connection to the internal buss bar has broken loose, (a common problem), and jarring it will get a temporary contact. Ron Patterson has posted several times, excellent photos of the connection, how it breaks, and how to repair it.
Here's an easy way to tell if the solder connections are broken at that bus bar. Take the starter cable off of the post and then try to wiggle the post. If it's loose, then the bus bar has almost certainly come undone.
Also, when you find that the starter doesn't work and is in its "dead spot," try wiggling that terminal with the battery cable still on it and see if that gets it to work. If so, it's your bus bar.
The good news is that repairing the bus bar isn't too difficult, if you know how to solder.
If the ring gear on the flywheel is worn, the starter bendix may get stuck in the gear when trying to start, making the whole engine stuck until the car is rocked in gear - or maybe it'll loosen when the starter is whacked. Easily checked with the hand crank - if the engine is stuck, then this may be the problem.
Easiest solution to problems with the electric starter is to use the hand crank instead - much more fun