Installed a cap tube water temperature gage.

[Phil P]

Hi

This is a 2012 RTV 1140

We were concerned that the electric gage was malfunction so I installed a cap tube gage at the thermostat housing.

We find the electric gage was working correctly and the engine coolant temperature is actually getting up to 235 to 240 under a long run on soft terrene.

We tried using a lower gear setting and that didn’t help.

My question is what is the maximum safe coolant temperature for this engine?

If these temperatures are too high then what shall I check to try and change this.

When we started trying to figure out what was going on we let the unit idle for an extended period of time the temperature didn’t exceed about 180 degrees. We then tried driving the unit around the repair facility compound and still didn’t get temperatures above 200 degrees. After 1 1/2 miles on an improved hard pan road the temperature was at 220 degrees. Another mile on a soft sand trail and we were at 235 to 240 degrees.

Any suggestions?

Phil P

 

[North Idaho Wolfman]

It sounds to me like your getting heat gain from the drive system that is affecting the engine coolant system.

Have you checked fan operations, and cleanliness of the exterior of the radiator and oil cooler coils?

 

[85Hokie]

235 - 240 is rather hot!
180 at idle is about right however.

Sounds to me that you have a radiator working BUT not well enough.

DO this - measure the temps at the upper rad neck and then the lower neck while good and hot. IT should drop by 60 some degrees! IF not - might be time to core the radiator or flush it good with a mild cleaning solution.

 

[Phil P]

Hi

Yes I have checked the fan and the radiator for obstruction all that is good.

I will check the temperature difference the next time I operated this unit and post the results here.

Thanks for the suggestions.

Phil P

 

[Tooljunkie]

Irrelevant but similar.
Just installed a new engine in a corvette, ran it up and temp started to climb. Right to 230 degrees. That is the threshold for the cooling fan protocols. I was concerned but after some googling i came upon some info, fan comes on low at 230 anf switches to high at 240. Not something im comfortable with.

I take it the fan is belt driven,not electric. Are fan shrouds intact?
With an electric fan, it could be wired with a switch to engage when it gets too hot

 

[Phil P]

Hi

I finally had time to check this out further.

The cap tube gage runs 240 when the unit has been run for about an hour under load. By my inferred thermometer the top and bottom of the radiator is running the same temp as the thermostat housing and the back of the head where the thermocouple is for the electric gage. When I plug the electric gage in it reads right at the point where the red and the white come together...

Anyone have any ideas?

 

[Blondie70]

I do believe 85HOKIE gave some great advice on this .

 

[REL1]

If you have the same temp at the inlet and outlet of the radiator and have it well cleaned externally then it may be plugged up internally.
But make sure you have it cleaned externally, I've seen many radiators come in the shop that have the bugs and weed seeds just blown back in the cooling fins. Looks good from the outside but it still can't flow enough air.
You can do a flow test yourself to see if it's plugged internally but if you don't have the experience it's hard to tell how plugged up it is unless it's really bad.
Or just take the radiator to a shop and have a flow test done then you'll know for sure.
I used to do a flow test for free at my shop if it was off the vehicle but thats been a few years ago

 

[eserv]

Hi

This is a 2012 RTV 1140

We were concerned that the electric gage was malfunction so I installed a cap tube gage at the thermostat housing.

We find the electric gage was working correctly and the engine coolant temperature is actually getting up to 235 to 240 under a long run on soft terrene.

We tried using a lower gear setting and that didn’t help.

My question is what is the maximum safe coolant temperature for this engine?

If these temperatures are too high then what shall I check to try and change this.

When we started trying to figure out what was going on we let the unit idle for an extended period of time the temperature didn’t exceed about 180 degrees. We then tried driving the unit around the repair facility compound and still didn’t get temperatures above 200 degrees. After 1 1/2 miles on an improved hard pan road the temperature was at 220 degrees. Another mile on a soft sand trail and we were at 235 to 240 degrees.

Any suggestions?

Phil P

The RTV 1140 seriously needs a bigger radiator. If you have a windshield and cab on it it WILL overheat! The Kubota dealership in Edmonton Alberta ( called Edmonton Kubota) have done some experimenting with an aftermarket radiator and fan and claim they have found a solution. It is expensive but from what I've heard ( from my local Kubota service rep.) it is the solution! You might give them a call, number is 1-780-443-3800.

 

[Phil P]

Hi

New information.

I just ran this unit in hard high gear for 4.5 miles. When I got back to the shop the temp was 240. I put the unit on the wash rack and wet the radiator with the water hose.

The result was the engine tem came down about 10 degrees but the radiator remained cold to the touch. My inferred thermometer showed the top hose at 90 and the bottom hose at 70. The fan was still running and the engine was at idle.

Drove it to the shop (100 yards)and radiator still cold to the touch temp the same.

It looks to me like I have a coolant circulation problem!

Phil P

 

[G.rid]

I'm not familiar with the machine but if it has a rad it should also have a thermostat. Have you pulled the thermostat to check it?
I did mine for my ATV last year, if I remember right it should start to open at 185 and be fully open at 200. I used a pot of water and brought it to a boil, using a thermometer to verify. Check the spec's for yours but it should be close.
If that checks out ok, I'd be looking at the waterpump next.
Good luck

 

[Phil P]

Hi

What fooled me was the fact that the unit would warm-up to 185 and not gets any hotter sitting and idling. Normally a bad thermostat causes them to over heat regardless of engine load.

Well now that I have the thermostat out it still warms up to about 185 at idle and doesn’t get any hotter until you load the engine.

At any rate the unit works correctly now that the thermostat has been removed. It reaches normal operating temp at idle in about 10 to 15 minuets and under heavy load only gets up to about 215.

If anything changes I will let you all know.

Phil P

 

[Tooljunkie]

When draining coolant it would be worth flushing rad. Also checking drained coolant for sediment.

Had a jeep that would idle all day not heat up. Highway for 15 minutes still fine. Drive it hard for 40 minutes would boil over. Thermostat,fan clutch and water pump. End result was a rad that had plugged cores top to bottom. The giveaway was the air blowing from from rad was cool,yet engine was near boiling over. Should have been hot as engine temp.

 

[Phil P]

Hi

Fortunately there isn’t much coolant loss when you remove the thermostat housing only about 1 qt.

Phil P