Kubota Grand L Cab Relectix Roof Liner

[Tjaltz]

I have a 2019 L6060HSTC and on hot summer days my AC struggles to keep the cab cool. I regularly blow out and wash the radiator and condenser fins and make sure my cabin external air filter and internal air filters are clean. I plan on tinting my windows eventually, but right now I have the roof removed and I'm preparing to install Reflectix foil insulation on the underside of the roof. My question for those who have done this or are familiar with the process is how much do I cover? I know I have to leave it open in the rear where the fan is, but did you glue the reflective foil to the whole underside of the roof, or just the area above the cab? Did you cover the evaporator cover and refrigerant lines? Thanks for your help.

 

[jk96]

Are you sure your air conditioning is working properly. Mine is a 2019 or 2020 model and my cab stays ice cold even in upper 90 temps.

 

[Tjaltz]

It puts out 60 degree air early in the day, but after 6 or 8 hours in the South Carolina sun, it can’t offset the heat coming through the cab glass and the air ducts in the plastic roof are heating the cool air output to the cab. It works great on hot overcast days. It’s all day in the sun where it struggles. I have to get my windows tinted as well.

 

[5030]

Here you go. Did mine last time I had the roof off to clean everything which was last spring... I used foil-bubble-foil Reflectix and glued it on with 3M spray contact cement. Coated both the roof and the Reflectix with cement, let it tack up and stuck it on. Have to cut it to fit first. I remove my roof every year and clean the underside and wash or replace the cabin air filter. I use both mine (I have a pair) for running hay so I get a lot of fine chaff up there. I also make sure my ac if fully charged and keep the rad and all the heat exchangers clean (AC and turbo air to air units). This last year I also had to fiberglass a couple of the rivnuts in the roof as the roof was cracking around them so I glassed them in and this last year I also replaced the perimeter gasket and the 4 spacer pads as my ld ones had lost their spongy (for lack of a better word) resilience, In other words they lost their springiness. A quick hundred bucks at your local, friendly Kubota dealer...lol

Made a huge difference in cooling ability in the sun.

I might add that I also added a 12 volt automotive cooling fan in front of the ac underhood heat exchanger wired to the ac compressor with a relay so when the electric clutch on the ac compressor is energized, the cooling fan is also running, pushing air through the ac heat exchanger. Really a benefit when the tractor is idling and airflow is less than when throttled up. She's ice cold all the time now. I have the factory tint on my windows and with my mods, it's plenty enough.

 

[5030]

I don't want any darker tint as I run mine after dark quite often. A dark tint would make it difficult to see after sundown. I would also suggest putting a shutoff valve in either line going to the roof for the heater. Use a ball valve and put it under the hood near the cab wall somewhere, either line works. The Kubota mixing valve likes to leak heated coolant even if it's turned off. With a ball valve, no heated coolant gets in the heater core until you turn it on.

 

[Tjaltz]

I don't want any darker tint as I run mine after dark quite often. A dark tint would make it difficult to see after sundown. I would also suggest putting a shutoff valve in either line going to the roof for the heater. Use a ball valve and put it under the hood near the cab wall somewhere, either line works. The Kubota mixing valve likes to leak heated coolant even if it's turned off. With a ball valve, no heated coolant gets in the heater core until you turn it on.

My L6060 has an in-line valve on the heater hose that goes to the heater core in the roof. When I set the cool-heat blend knob to the coolest setting, a servo closes that valve and I don’t really feel any hot water running through the heater core hoses. If the insulation and tint don’t improve it, I may have to add the ball valve.

 

[Tjaltz]

Here you go. Did mine last time I had the roof off to clean everything which was last spring... I used foil-bubble-foil Reflectix and glued it on with 3M spray contact cement. Coated both the roof and the Reflectix with cement, let it tack up and stuck it on. Have to cut it to fit first. I remove my roof every year and clean the underside and wash or replace the cabin air filter. I use both mine (I have a pair) for running hay so I get a lot of fine chaff up there. I also make sure my ac if fully charged and keep the rad and all the heat exchangers clean (AC and turbo air to air units). This last year I also had to fiberglass a couple of the rivnuts in the roof as the roof was cracking around them so I glassed them in and this last year I also replaced the perimeter gasket and the 4 spacer pads as my ld ones had lost their spongy (for lack of a better word) resilience, In other words they lost their springiness. A quick hundred bucks at your local, friendly Kubota dealer...lol

Made a huge difference in cooling ability in the sun.

I might add that I also added a 12 volt automotive cooling fan in front of the ac underhood heat exchanger wired to the ac compressor with a relay so when the electric clutch on the ac compressor is energized, the cooling fan is also running, pushing air through the ac heat exchanger. Really a benefit when the tractor is idling and airflow is less than when throttled up. She's ice cold all the time now. I have the factory tint on my windows and with my mods, it's plenty enough.

Thank you. Pretty much what I’m doing.

 

[5030]

Make sure when you reinstall your roof NOT TO TIGHTEN THE ATTACHMENT SCREWS DOWN REALLY TIGHT because you'll pull the rivnuts out of the plastic roof and crack it. Just snug them down all around. The perimeter gasket will seal it. When mine was installed at the factory (I presume) whomever installed it reefed on the screws and started cracking the roof which I had to repair.

 

[Tjaltz]

Thanks for the tip. When I took mine off I noticed they were not that tight, just snugged up.

 

[Fallon]

My L4060hstc struggles to stay not hot in the mid to high 90s. Might go this route.

When mowing I have to clean all the radiator screens up font often. Sometimes daily I have to blow out or even wash out the radiators themselves as they get plugged up with fine dust & debris the screens can't keep out.

 

[Tjaltz]

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.

 

[5030]

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.

 

[5030]

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.

 

[Fallon]

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.

 

[5030]

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.

 

[5030]

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.

 

[chim]

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.

 

[Williy]

Tjaltz​

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!

willy

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