electrical trouble cub cadet 7305

[shyza]

I have been troubleshooting my cub 7305. The symptom is battery discharging while running or not in about 15 min. New battery, altenator/voltage regulator removed and checked twice, starter also removed and checked twice. Whith a fully charged battery as soon as the key is turned on (not start) the voltage at the battery drops to 11.5vdc and continues to drop. I have purchased the manufactures repair manual only to be dissapointed.. the wireing diagrams appear to be for different models.
Whith the engine running I found a large relay that goes to some kind of a air intake heater? after removing the large wire from the relay the tractor began to charge and all was ok.
What is this heater looking thing in the air intake ? Is it necessary? What controls it? the relay coil stays energized anytime the key is on or started.
Thanks
Bob

 

[kebo]

Has it always done this since you owned this tractor??? A proper wiring diagram would be great, but since you didn't get the right diagram for your particular model, you're sort of in the dark on how it's wired.

The "heater looking thing" I believe is the preheater for the air intake, this helps it crank up easier in cold weather. I do not think you need it activated AFTER the engine has cranked up, regardless of how cold it is.

On *most* tractors, when you turn the key switch to a certain position, that relay will become energized which activates the preheater. Moving the key from that position *should* de-energize that relay. It's possible that the wire that controls that relay is wired to the wrong terminal on your key switch. I don't have a Cub tractor, but maybe someone who is familiar with them can jump in and tell how exactly it is supposed to work. Maybe the wiring diagrams you have at least show an engine preheater circuit?? Look them over closely again, it might give you a clue. Good luck!

 

[shyza]

Kebo,
Thanks for the reply. This problem just started.. Since this posting I was able to verify that the part is indeed a heater..
Unfortunately either wire diagram show the heater.

 

[ETpilot]

I'm not familiar at all with the Cub Cadet. I have a similar air preheater in my Dodge Diesel. From what you describe it sounds like the pre heater relay is stuck on. So as soon as you turn the key on it starts draining the battery. Removing the relay wire, as you have done, stops that action and you begin charging again.

I would test the relay to see if it is stuck on. You may just need a new relay.

The pre heater, as mentioned, is there to help starting primarily in cold weather. You may just have a simple on-off controlled by the ignition switch.

On the Dodge truck it is thermostatically controlled by the Power Control Module. It only turns on in cold weather. However, the 2 relays do stick on and cause problems. An indicator light in the powerl circuit would let you know its condition.

 

[shyza]

Thanks for the info.
I have verified the relay is being told to work. It appears from the online parts breakdown that there is a controller. I have begun conversation with folks like yourself to determine if the contol is timed or sensed.
I have used the tractor with the relay unwired. This would be a permenant fix for most but I have issues with things not working as designed. I have started an all out search for the proper schematic. I have contacted Mitsubishi with no luck. I may have to resort to parts changing.
Currently If I had to order a part it would be the controller and hope it operates on time instead of a temp sensor.
Thanks again.
Bob