Kubota Grand L Cab Relectix Roof Liner

   / Kubota Grand L Cab Relectix Roof Liner
  • Thread Starter
I always blow out my radiator and condenser with a radiator genie after I mow or brush hog. If I’m out all day and it’s hot, I’ll blow them out on my break. When the condenser starts to clog, the cab warms up fast. The reflectix on the underside of the roof helps keep the recirculated air cool. I almost always run the AC in recirculate mode. I’m getting the windows tinted, but I already see an improvement with just the reflectix.
   / Kubota Grand L Cab Relectix Roof Liner #12  
Recirc keeps the crap out of the evaporator and heater core for the most part but they still need cleaned once in a while.

My biggest improvement came from the 12 volt fan I placed tight up against the ac condenser and wired to the compressor clutch with a relay. When the clutch is engaged the fan is on. Helps a ton, especially at low engine rpm.
   / Kubota Grand L Cab Relectix Roof Liner #13  
I might add that I carry my 'handy-dandy' Bauer 20 volt Li-Ion battery powered blower beside the seat in the cab tractor (fits real nice there) and I blow my rad and ac condenser as well as my air to air heat exchanger, mine is turbocharged so it has an air to air heat exchanger out front as well, regularly in the field when I'm mowing or bailing hay. When I rake with the open station I don't produce much in the way of fines so it gets blown out when I get back to the farm.

I had a heck of a time keeping my long gone 5030 HSTC cool and finally cut poly wings that I attached to the front mounts that channeled the cooling air more efficiently to the engine fan. That works as well.
   / Kubota Grand L Cab Relectix Roof Liner #14  
As usual my machine had some issues in the mid 90s this summer. After mowing for a good few hours in the heat of the day things get toasty. My first sign is always the A/C cutting in & out. If I check the temp gauge it will be over 60-70%.

Letting it cool down for a bit or backing off on the go pedal will let me wrap up a job nearing completion. Without getting the temp gauge into the red. Blowing out all the various cooling cores under the hood will help. But on the hotter days there just isn't enough cooling under the hood for the engine & A/C.

As somebody else noted I do evening work & snow, so not excited about tinting the windows. Will probably do the insulation thing next time I pop the top. But that won't help the engine on the hot days.

No sign of any problems with engine or A/C temp problems pushing it hard last week in the 80s with A/C on. Radiators were really packed with seeds & chaff from 2 days of mowing hood high grass too when I loaded up to head home.
   / Kubota Grand L Cab Relectix Roof Liner #15  
You might want to add plastic wings to each side of the front support (just behind the battery) to channel the air flow better across not only the heat exchangers but the ac condenser as well. I did that plus the reflectix as well as the ball valve in one of the heater hoses (don't matter which one) and my ac will freeze you out, no matter what the ambient temp is. I also added a 12 volt cooling fan secured against the condenser that cycles with the AC compressor.

I only have the OEM tint on my windows.

The climate control system on Kubota's could have been better designed.
   / Kubota Grand L Cab Relectix Roof Liner #16  
Again, I carry a Bauer 20 volt cordless blower behind the seat and blow out the rad and heat exchangers often while cutting hay or bailing. Fit6s quite nicely behind the seat on my M9.
   / Kubota Grand L Cab Relectix Roof Liner #17  
The thermometer shows the discharge temp in the L4240 before lining the roof. It didn't change following the lining, but it seems to have made a difference. Best comfort on really hot days is had by keeping the fresh air closed and running the fan on medium. It's also possible I'm imagining it:)

EDIT TO ADD - When I bought the 4240 it had a band of tint at the top of the windshield and doors. First thing I did was remove it. The factory tint is sufficient for me, and I doubt that added tint would be welcome at night. I'm not aware of any aftermarket tint that doesn't eventually get scratched up.


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   / Kubota Grand L Cab Relectix Roof Liner #18  


I keep the outside air closed as the a/c system works a lot more
efficiently. Even when its 112 defrees F I can not have the a/c on
full blast with 112f its too cold!