48 cub with electrical problem

Wed Jul 02, 2014 10:38 am

This week my 48 Cub which we use to cut the lawn stopped running while in use. We could not jump start the battery, but I was able to tow it and jump-start it with my car. When it is running it had no electrical power (the lights did not work). The problem began this week, where should I start trouble shooting? The battery is good.
Your help, as always is appreciated!
Thanks for your time, Phil

Re: 48 cub with electrical problem

Wed Jul 02, 2014 10:48 am

i'm going to assume that you have a magneto. you have a bad connection on the battery cable(s) not connecting power to the starter terminal

Re: 48 cub with electrical problem

Wed Jul 02, 2014 6:28 pm

Battery powered ignition systems will still work and engine run at around 4.5 volts from the battery.

First thing is to fully charge the battery. Clean up all battery terminals and connections.

Test the battery at the auto parts store or do the voltage drop test.

Guessing, you have a problem with the cutout/regulator and or the generator.

Re: 48 cub with electrical problem

Thu Jul 03, 2014 10:36 am

Thank you guys! I will start trouble shooting this weekend.
:{_}: Have A Great 4th of July! :{_}:

Re: 48 cub with electrical problem

Thu Jul 03, 2014 5:22 pm

As was said already battery connections are key... everything is grounded to the frame (how many wires on the lights are a clue) so it is VERY IMPORTANT that both the positive and negative wires and their connections are good. Cheap bolt on battery connections will work (at least on 12V Cubs) but are always suspect. So is where the ground goes, I prefer a braided one to the bottom of the battery box, that is directly to a casting. All the power (negative wire on 6v) goes to the lug on the starter with a brown wire going back to the dash for lights and ignition.

Like Bob said, a Cub requires little to continue to run, starting and lights are a different story.

Re: 48 cub with electrical problem

Thu Jul 03, 2014 9:32 pm

Phil:

If IRC, your 48 is a magneto equipped Cub right? If so then what you have is indeed connection problems. Also, not being able to boost/jump start through the battery tells me that, and being able to pull start it pretty much confirms it. Generally this indicates bad grounds. Especially as Larry indicated :

Buzzard Wing wrote:I prefer a braided one to the bottom of the battery box, that is directly to a casting.


This is what I use and it has been a real dependable ground. Make sure that the starter lug is clean and no corrosion present.

One thing to check as well is the condition of the battery. I had this exact situation when I went to start Ellie after she sat since the beginning of October last as I was too ill to do much over the winter. Couldn't boost, the trickle charger would not charge - went into fault mode, the charger wouldn't charge the batter. Took it in to the shop, did a load test - toast. New battery and poof .. problem solved :-) There is always that fix too .....

Re: 48 cub with electrical problem

Fri Jul 04, 2014 10:29 am

Check all ground connections. Make sure they are clean and tight. :)