Starter motor question

[Au revoir, Gopher]

A few years ago I bought a tractor (at auction). It always lugged when starting, but would always start after 20 or 30 seconds. Then, one day, it wouldn't turn over. I thought battery and got the truck to give it a boost. Just went 'click'. Tried a couple more times and it finally turned over and started. It did that to me a few more times and then finally just gave up.

I took the starter out and as I was taking it apart, cleaning and checking, I noticed that one of the brushes was stuck in its track. After I was done cleaning and checking, I got the brush moving freely and reassembled the starter. Put it back in the tractor and the tractor started better than I had ever seen it start before. The next few times I used the tractor it just fired up perfectly. Now it is back to lugging.

My plan is to dismantle the starter again and give the brush assemble a thorough going over cleaning and looking for anything that might be causing the brush to bind. The question is, is there an sort of lubricant that I should use on the brushes/track? I was thinking maybe graphite. Not sure if I would just be making things worse.

And if it does it again, I will just replace the brush assembly.

ARG

[Dean2]

Dielectric grease.

Dielectric grease acts as a lubricant, a sealant, an insulator, and a protectant when lightly used on these applications.

Battery terminals
Spark plug boots
Bulb sockets
Trailer connectors
General electrical connections
General plastic or rubber lubrication
Helps prevent voltage leakage
Helps insulate the electrical connection in frigid conditions
Protects against water damage
Protects against corrosion
Protects against dirt and grime
Protects against heat damage
Protects against material bonding
Protects against electrical overheating

[MyAlberta]

How does the length compare to a new brush. Not long enough and they can tip and bind. Spring pressure good?. I’d stay away from greases as they attract contaminants.

[lannie]

I would not use dialectic grease on brushes at all.
The brushes are running against commutator bars and I would make sure they are very clean and nothing in between each bar. Your best bet is taking the starter in and getting it serviced somewhere that rebuilds starters etc. Used to be a place called Fort ignition or close to that name by intersection of yellow head and ft. Road

[Au revoir, Gopher]

Originally Posted by Dean2

Dielectric grease.

Hadn't thought of that one...

Originally Posted by MyAlberta

How does the length compare to a new brush. Not long enough and they can tip and bind. Spring pressure good?. I’d stay away from greases as they attract contaminants.

They are well within spec. according to the service manual. Springs seem fine. That is my concern about lubricating them.

Originally Posted by lannie

I would not use dialectic grease on brushes at all.
The brushes are running against commutator bars and I would make sure they are very clean and nothing in between each bar. Your best bet is taking the starter in and getting it serviced somewhere that rebuilds starters etc. Used to be a place called Fort ignition or close to that name by intersection of yellow head and ft. Road

I'm not thinking about lubricating between the brushes and the commutator, but the track that the brushes ride in. I cleaned the commutator and checked between the bars, that all checked out.

And, of course, when I fired it up this afternoon it started perfectly... no lugging. Murphy's Law in reverse, I guess.

ARG

[barbless]

If it just goes click click could be the solenoid. We use to carry a small hammer are something similar to give the starter a tap or whack as it may be. Usually just a tap or two to get it to engage.

[Big Grey Wolf]

I use a 12 volt battery in my 75 year old 6 volt Ford tractor. The starter does not dare not spin and start tractor in 10 seconds. More serious your brushes appear to need more fine tuning or replacement. Just as mentioned starter rebuild is highly recommended. A good starter required especially when doing cold starts in winter, a can of ether sure helps take load off of the starter.