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.