# Kubota M9000 Condenser Fan Addition Problem



## dvcochran (Oct 1, 2017)

I have wanted to do this project for a while and finally getting around to it. M9000's are known for their small condenser and I have read from several sources that addiing a fan helps.

I purchase a 10" racing grade fan from Summit Racing and a 12-volt electro-mechanical relay kit from a local parts store.

I used a 30 amp fuse for the load (30) and the + wire to the fan on (87).

I used a 20 amp fuse for the relay coil switch leg (86) which comes from the compressor ON power wire. I spliced directly into the wire near the compressor.

Tied all the grounds to negative on the battery.

As soon as the compressor tried to come on it blew the 10 amp fuse in the fuse block for the compressor. I even went up to a 20 amp fuse and it still blows.

I removed the wire from the compressor and used the switch that came with the relay kit. It is tied directly to the battery with the same 20 amp fuse. This way the fan powers up fine.

From what I can find the relay coil only pulls around 160mA. I am stumped on why I cannot control the fan by the compressor wire when all it is doing is energizing the relay coil.

Weather permitting I will be back in hay next week and would really like to figure this out before then.

Thanks for any help.


----------



## Palmettokat (Jul 10, 2017)

There two possible things I can think of: one there is issue with the relay. The second is you have got the ground and positive tied togehter somewhere. I assume Kubota uses the black wire as ground as most 12 volt systems do but test and be sure.


----------



## dvcochran (Oct 1, 2017)

I checked the wiring to the compressor. You can easily see the negative/ground wire landed right on top of the compressor. The other wire (the one I tried to use) would cycle 12ish volts when I turned the A/C on/off via the fan switch. The biggest stumper is when I put a 20 amp fuse in the fuseblock and it still blew. It looks like the compressor with is a 14 gauge wire so that is as high as I think I should go amperage wise.

The two grounds are the one for the fan and one for the relay (85), both are tied to the negative on the battery.

I agree there may be an issue with the relay but it seems the coil would fry if too much current went through it. I dont know if my amp clamp will go below a 10th of an amp but I am going to test it tomorrow.

I thought abot using a super low current SCR but dont want to pay the $130 price tag.


----------



## Tx Jim (Jun 30, 2014)

Have you considered wiring fan relay into the circuit that controls the inj pump solenoid?


----------



## Palmettokat (Jul 10, 2017)

Well how about the fan itself? Are you sure it works? Have you tried connecting it direct to the battery post to see if it works?


----------



## dvcochran (Oct 1, 2017)

The fan works fine. As said before, right now it is wired to the battery through a toggle switch that came with the relay. The switch is wired directly to the battery through a 20amp fuse.

I did not consider wiring it to the injector solenoid. That would at least let it cycle with the key switch.

I was thinking it needs to cyle with the compressor.


----------



## Palmettokat (Jul 10, 2017)

Sure seems like something simple is being missed. I reread your orginial post. Do you have the relay in the circuit with the switch now? In reading do not see that mentioned. If the relay is not in the circuit now, believe the relay is the problem or is it possible the relay is not wired correctly?


----------



## dvcochran (Oct 1, 2017)

I went back and just unwired everything and started over. Not sure what I had wrong but it is working correctly now. Pretty sure I had to have a ground wire running to the compressor wire somehow. One of my routing brainfarts.


----------



## Palmettokat (Jul 10, 2017)

The simplest can stump the smartest.


----------



## dvcochran (Oct 1, 2017)

I am definitely the former not the latter.


----------



## 69zfarmer (Jun 17, 2012)

Is your M9000 a early model or does it have a "Ultracab" decal on the side glasses? Did the fan help the cooling? I have a early M8200 and it could use some help cooling.


----------



## dvcochran (Oct 1, 2017)

It is not an ultra cab. We have had rain here for 10 days straight so I have not tested it with a heavy pull during an afternoon sun. From what I have done since adding the fan it seems to have helped quite a lot, especially when not moving.

I dont know how similar they are but I do know you have to be diligent about cleaning the condenser.


----------



## Palmettokat (Jul 10, 2017)

Not sure the design of the condenser on the Kubota but have friend who had fleet of Kubota's and he said he uses leaf blower and not pressured water so not to bend the fins on such as radiator.


----------



## dvcochran (Oct 1, 2017)

Once or twice a year I will used coil cleaner to be sure the condenser is clean. I made a simple 90° nozzle go get between the radiator and condenser with 1/4" copper line and flattened the tip a little. Works really good and I have never had any fin issues. I believe the common mistake made when cleaning a condenser or radiator is simply getting in a hurry. I never leave either wet or cool, where any rogue seed could get stuck and try to grow. I blow with air, then (coil cleaner if using)water, then lots of air until I see no moisture, then run the tractor for a good while so everything is good and hot hoping to kill any overlooked seed. So far so good.

I cut hay yesterday and the condense fan addition definitely made a noticable difference.


----------

