rtv 1100 cooling

R

rogerw

New member
I have a 2011 model. i have tweaked many things for improved performance such as: adj throttle cables, both pedal and pump cables to obtain lower idle and higher wot speed. Did not touch fuel pump or screw. then readj servo linkage for better neutral. This smoothed shifting, just completely stop and return to low idle. Top speed is now 28-29 mph, all good here. I then adj and readj servo valve screw trying to improve hill climb speed and start up (wheel spin). Could not accomplish both so went with better hill climb. Will wheel
spin in 2wd low only when on hard dry soil.
Now for my cooling issue. When running on paved road and wot 28 mph I have about a 3 mile range before reaching the red zone in 90 deg ambients. I have checked the temp with infrared gauge and is pretty well dead on. Rad and air cleaner clean out is done frequently. So looking for a little more cooling. Have considered installing a low profile pusher fan on front side of rad in addition to standard and operate off it's own switch. Wondering if two of those hose billets (7" lg) installed in upper and lower hose would be enough. These are used on dirt bike/atv's when racing. Can anybody add some insight here?
So this is my first new thread, Thanks to all. Rogerw
 
Hey Roger, I don't have an 1100 but none of my 900's have ever got near the red unless the radiator was full of seed or grass and thatwas the case when I was pulling an oak skidded mineral trough with a full load of minerals in it for about 1/4 mile. The other time on the '05 my oem fan quit working and I replaced it with a flex a lite brand 12" . I saved a bundle and it did an excellent job never going up on the gauge much at all. If the wires are reversed it can be a pusher or puller but then the fan blades would need adjusting accordingly. There is a thread on here of me changing it out with details but I just used the original shroud and fitted it in place like the oem with a little "bordercollieing" maneuvering. Are you sure that your fan is kicking on? If your engine is warmed up you can usually hear it when the key is turned to the accessory position or else by pass the sensor and test it at the plug with 12v.
Flex a lite used my testimony in their catalog last year and a complete full picture of my avatar that I use here. It worked great for me and saved $$$$. Their wiring colors don't necessarily hook their red to kubota red though.

edit: link to fan info : http://www.nettractortalk.com/forums/showthread.php?t=13665&highlight=flex+lite&page=3 bordercollie
 
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Roger I'm running a turbo/more fuel/hydro adjustments etc. on my 2011 RTV 1100 and my expierence is the same as Border's. Like everyone else on the forum I pull lots of heavy stuff and it never gets hot and when it does warm up the fan brings it right back down. I would check the exsisting system for issues before you add any further cooling.
 
Yea, Bordercollie, I have read your flex o lite thead. Do you think there is a significant improvment? I need additional cooling. My oem fan seems to work great coming on before reaching mid point on gauge. Also keep in mind this is 1100 with all different radiator mounting. Thanks, the pictures do help for my mounting concerns.
Rogerw
 
I dunno seeing lots of overheating problems on these newer products. Maybe they should stick with the 900 and call it a day.
 
Roger: I'll ask the stupidest question of the day--is your coolant reservoir adequately filled with fluid, and is the fluid good? My 1100 was prone to peg over right to the edge of the red band ... I topped off the coolant reservoir and that cured it.
 
rogerw said:
Yea, Bordercollie, I have read your flex o lite thead. Do you think there is a significant improvment? I need additional cooling. My oem fan seems to work great coming on before reaching mid point on gauge. Also keep in mind this is 1100 with all different radiator mounting. Thanks, the pictures do help for my mounting concerns.
Rogerw
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Hey Roger, Have you changed the coolant to a higher ratio or anything? I read a post on here months ago that more antifreeze is not necessarily better. Also the manual on the 900 said to keep the ethelene glycol antifreeze less than 50 %.. or it could overheat. As Heatwave mentioned, how is the level in the radiator and reservoir? You machine is so young, has it always done this?
My F-a-l fan made a big difference in how fast the temperature gauge dropped after the fan came on over the original but I would check everything else first before replacing the oem fan. PA Jeep sounds like he is pulling a lot with his 1100 engine and hasn't had your overheating problems.
If you do decide to add a fan check the CFM on any you look at because they really vary. bordercollie
 
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'Scuse me. Brain cramp. I don't have an RTV 1100. I have an RTV 900. But I reaffirm my earlier comment about ensuring that the coolant reservoir is adequately filled.
 
make sure the radiator is not semi plugged up internally. In autos, overheat at high speeds is most always stopped up radiator.
 
You all bring some good points. I moniter the coolant level and do add a little oh every 2-3 weeks which is straight antifreeze. So maybe I need to add water, had'nt thought about. Am thinking of removing rad and doing a internal cleaning and flow check. I changed thermostat this spring, no change. This rad core appears to have a heavy coat of aluminizing on exterior. Need to peep inside. Thanks Will post more as I go.
 
Good Luck Roger. So your machine has been loosing a bit of coolant for a while ,and you have replaced the thermostat because of this overheating? And your oil looks good and the water isnt oily in the radiator? Those worm screw type hose clamps will sometimes allow small amounts of coolant to leak out when under pressure so I check mine when I change oil. I also read on the 50% ratio on the antifreeze that the stuff doesn't dissipate heat as well at high concentrations and that is why it can make an engine run high in the heat range. We have a lots of minerals in our water so we use distilled with our antifreeze to help keep down scale .
I remember my Daddy working on the first truck I ever had (a notorious orange with black stripe Ford Courier- It looked like a pumpkin with those big round headlights) 1979 model. It ran hot like this and it turned out to be the impeller in the water pump. It had come out of position . He pressed it back on and it kept on going... :) bordercollie
 
If you're adding antifreeze occasionally ... there's a problem: it has to be going somewhere. Eliminating the source of coolant loss should resolve your cooling issues.

Also ... respectfully suggest that you not add straight anti-freeze ... that stuff has to be cut with water. A 50/50 mix will take the coolant's freezing point down to -30 deg. (+/-) while still removing excess heat from the engine.

A 70/30 (antifreeze/water) might take the freezing point down to -70 deg. (+/-), but it will reduce the cooling capacity, so that your engine will start overheating prematurely.

Good luck, Mate. Please let us know how this gets resolved. We go to school on one another here. I feel like Border Collie has me fairly well-prepped for my Kubota PhD now.
 
I have a RTV1100 2009 200hrs and have never seen the temp gauge go much over the normal range. My RTV900 2008 was always at the near edge of overheating but that was the way all the 900's were setup. 1100's run allot cooler, or at least according to the temp gauge. And I've pulled a 4,200 lb roller in 80 degree temps over lawns for hours and never overheated.

I you're overheating, reaching the red zone, you definitely have a problem.

So, you changed the thermostat so that eliminates that.

You cleaned the rad and screen so air flow is good and hopefully you hear the fan coming on, so we will assume that is okay.

Next would be looking for tiny leaks to explain why you keep adding fluid. Pin holes in the rad, pin holes in the hoses. Possibly a collapsed hose, but highly unlikely. Only way to check for a collapse is to remove and examine. Pin holes should show signs of wetness on the hoses or rad.

Rad cap is set for about 15psi. If it is weak the system will overheat and or force out coolant because the cap pressure raises the boiling point and provides better cooling. Possibly a new cap would be in order.

Pump itself could be bad, but again highly unlikely.

Head gasket. Small leak here will cause overheating and may or may not show signs of oil in the coolant. This is worse case scenario and hopefully not your problem.

Adding straight coolant is never a good idea. As suggested 50/50 mix is the best and you can buy premix coolant to avoid the mess if you find it easier.

You didn't give the year or hours and any extreme conditions you are running in. I'm in Canada and see 85 to 95 F in summer and -4 to -8 F in winter. So have a wide range of temps. Most here use there RTV's in hot weather, work them hard and have no problems. Running down the road at 25mph is not what I would ever call working an RTV hard. Pulling a fully loaded trailer with 2,000 lbs at that speed and up a hill would be what I'd call working my rtv.

My suggestions would be new rad cap, drain coolant, flush system with water and then replace coolant with new 50/50 mix or premix. Check for leaks.

And Test.

Good luck
 
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Heatwave said:
I feel like Border Collie has me fairly well-prepped for my Kubota PhD now.
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Heatwave,:tiphat: I got my degree from DTU and I also have a BS degree from a place in Louisiana. But I do get jollies from being whatever help I can. :) bordercollie oh yeah, DTU is ... Duct Tape University and is located not far from WD 40 . :)
 
Just an update on my cooling issue. Grabbed my infrared temp gauge on a 70 degree day and went for approx 6 mile ride to get temp gage to 1/16 th inch of red zone. Quickly stopped raised bed and checked cooling system temps at various points. Most points read from 220-228 degrees except yellow trans filter in front of cooler read 238 degrees. What about this Bota techs,others, is this too high temp for tranny oil. Do I have a trans problem? Thanks for all the wisdom !! Roger
 
I just have the 900 with the hydraulics. However even after 4 hrs of heavy use, my hydraulics never got anywhere near the temperature you mentioned. Do you have a cooler under the seat? The xt model 900 does and it is always catching straw because the engine fan just sucks the stuff in. I added the cooler mentioned in this thread and put it under the hood and the temperature stays around 125 even after heavy use . http://www.nettractortalk.com/forums/showthread.php?t=14755&highlight=weed+wiper
 
Here is one thing I am learning. The temperature is controlled by the fan switch located at the thermostat housing. Your gauge should not leave around 1/4".
I have a new 1100 and at 20 hr it overheated. Completely boiled over. My fan was not coming on unless I tapped the fan switch with a screw driver so dealer sent me another one. My gauge hangs around 1/4" but the fan is a huge part of this because it kicks on and off a lot.

Now I have been adding a little coolant also and have checked thoroughly for any signs of a leak. When it boiled over I added straight antifreeze also, learning that's not a good ideal. My jug will loose about 1/2" in 4 hours. There is no sign of coolant in oil because I changed after the overheat and no sign of any coolant in exhaust. I put a small plastic jug on the coolant reservoir bottle overflow tube to make sure it's not leaking there. There is a very strong smell at each of the radiator caps but no signs of a leak. I am going to flush and fill with proper coolant mix, monitor coolant level and if it continues its going to the shop.

As for your high temp range when your gauge gets halfway tap your brass fan switch and see if it doesn't go off. I bet if you change it your temp gauge will stay low. The high heat your running could be evaporating coolant.
 
Hello Hersheyfarm, Am I understanding this that the fan will kick on and off at temps above normal operating. I will tap mind and check this when i get a chance. It is in kubota shop now. The only thing they are doing is change the middle rad cap housing. It will distort at high temps (another weakness in the system) so the mechanic says. The distortion cuases a press drop and system will not circulate properly at reduced pressure.
Did the new fan switch correct your problem?
Thanks for the good info, will come back on when I have more.Roger
 
rogerw said:
Hello Hersheyfarm, Am I understanding this that the fan will kick on and off at temps above normal operating. I will tap mind and check this when i get a chance. It is in kubota shop now. The only thing they are doing is change the middle rad cap housing. It will distort at high temps (another weakness in the system) so the mechanic says. The distortion cuases a press drop and system will not circulate properly at reduced pressure.
Did the new fan switch correct your problem?
Thanks for the good info, will come back on when I have more.Roger
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Hmm.. I'll be surprised if that helps you not overheat. Your fan should be on nonstop then if your above 1/3. My first fan switch would not kick on at all unless I tapped it, but this was after my overheat. I'm not sure if my overheating was because I'm loosing coolant or the switch went bad. But it was for sure bad at that point. I'd say you need a new fan switch now, I think if you overheat it can kill the switch. And then send our unskilled Kubota dealers chasing a secondary problem first.
 
rogerw said:
Hello Hersheyfarm, Am I understanding this that the fan will kick on and off at temps above normal operating. I will tap mind and check this when i get a chance. It is in kubota shop now. The only thing they are doing is change the middle rad cap housing. It will distort at high temps (another weakness in the system) so the mechanic says. The distortion cuases a press drop and system will not circulate properly at reduced pressure.
Did the new fan switch correct your problem?
Thanks for the good info, will come back on when I have more.Roger
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any update on your situation? very curious about the rtv 1100 overheating issues.
 
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