Standard RMK VS Pro Cooling System

[Merlin]

Good evening,


I've been reading about how much more effective the cooling system is on the standard RMK model over the Pro yet after examining the plumbing of the coolers on the standard model, I'm at a loss as to why?

It would appear that the front heat exchanger on the standard RMK would see maximum flow until the thermostat starts to open at which point the flow would begin to pass through the rear coolers. Given the logic that a fluid takes the path of least resistance it's surprising that the RMK doesn't actually run hotter as the coolant would favor the front cooler circuit over the rear when the thermostat is wide open? You'd think the cooling system would be more effective if all three coolers were plumbed in series?

One can't argue with the fact that the standard RMK runs cooler than the Pro, I just wish someone would explain how it's possible.

 

[AdrenalineAddict]

3 total heat exchangers versus 2

 

[gunnerthesnowman]

I added the front cooler to my 2012 pro BB , best $150 I ever spent , the tubing to the front cooler is smaller , so with the T-stat closed the front cooler always flow ( takes a little longer to warm up from cold starts ) once the T-stat starts to open there is enough pressure in the system to make the coolant flow to the main cooler.
I also run Terra Alps T-stat , with both of these mods , my sled runs 37-40 C

 

[Merlin]

I added the front cooler to my 2012 pro BB , best $150 I ever spent , the tubing to the front cooler is smaller , so with the T-stat closed the front cooler always flow ( takes a little longer to warm up from cold starts ) once the T-stat starts to open there is enough pressure in the system to make the coolant flow to the main cooler.
I also run Terra Alps T-stat , with both of these mods , my sled runs 37-40 C

I guess that's the key.

The water pump is sized big enough that it produces enough flow to keep the coolant moving through both front & rear circuits regardless of them being plumbed in parallel.


Thanks!

 

[AndrettiDog]

I guess it comes down to where and how you ride. Here in Colorado I've never really had a problem overheating. I'm accustom to putting down my ice scratchers on the trail. The only time I've seen issues heating up was on a dirt road in the spring, but everyone was struggling.

Are you guys that want more cooling riding the trails a lot or is there another reason for the issues over heating? The third cooler seems helpful. It does add a little weight.

 

[Merlin]

I guess it comes down to where and how you ride. Here in Colorado I've never really had a problem overheating. I'm accustom to putting down my ice scratchers on the trail. The only time I've seen issues heating up was on a dirt road in the spring, but everyone was struggling.

Are you guys that want more cooling riding the trails a lot or is there another reason for the issues over heating? The third cooler seems helpful. It does add a little weight.

Well,


In my particular application I have to admit that I'm guilty of doing a few things that are definitely contributing to poor cooling:

1/ Driving too slow(teaching my my son to ride)

2/ Gear bags on tunnel(Large & small Mountain Addiction gear bag & small fuel can)

Unfortuantely, these are things that can't be avoided so I do what I can to make the best of a bad situation:

- Scratchers down 99.9% of the time

- Full snowflap(Dragon model)

- Water Wetter coolant additive

- Fuel plug in ethanol mode

- Plenty of stopping to cool down


Thinking of:

- Adding more fuel throughout the mid-range

- Adding addtional cooler/s



When riding in decent conditions with speed, the cooling system performance is acceptable but step out of those parameters & the temperature climbs.

To say that the cooling system functions fine for a deep powder machine is accurate, but to say that it has no flaws or room for improvement is stretching it.

 

[live to ride]

I added the front cooler to my 2012 pro BB , best $150 I ever spent , the tubing to the front cooler is smaller , so with the T-stat closed the front cooler always flow ( takes a little longer to warm up from cold starts ) once the T-stat starts to open there is enough pressure in the system to make the coolant flow to the main cooler.
I also run Terra Alps T-stat , with both of these mods , my sled runs 37-40 C

hey gunner, would you mind sharing some info on your front cooler install? is it the rmk cooling system? was it a complete kit? how difficult was it to install? thanks

 

[gunnerthesnowman]

hey gunner, would you mind sharing some info on your front cooler install? is it the rmk cooling system? was it a complete kit? how difficult was it to install? thanks

Go to this link ,it was not my idea , it show and talks about some of the details , he made his cooler 15" long , I made mine 18" long ( as I installed a 870 big bore motor ), its two 4" welded together, fits right between the stock tunnel cooler

http://www.snowest.com/forum/showthread.php?t=324778

 

[live to ride]

Go to this link ,it was not my idea , it show and talks about some of the details , he made his cooler 15" long , I made mine 18" long ( as I installed a 870 big bore motor ), its two 4" welded together, fits right between the stock tunnel cooler

http://www.snowest.com/forum/showthread.php?t=324778

thanks gunner

 

[moosesp]

I added the front cooler to my 2012 pro BB , best $150 I ever spent , the tubing to the front cooler is smaller , so with the T-stat closed the front cooler always flow ( takes a little longer to warm up from cold starts ) once the T-stat starts to open there is enough pressure in the system to make the coolant flow to the main cooler.
I also run Terra Alps T-stat , with both of these mods , my sled runs 37-40 C

Its great to see that the extra cooler worked for you too!

Moose

 

[jaida]

I think the cooler is a must for some people depending on the conditions they ride. I run a 2012 std rmk, ride with my son, split between flat land and mountain riding. The extra weight for me is a non factor, I dont have to watch the temp as close. The scratchers are installed just in case I need them but very rarely do they go down.

 

[Powderforlife907]

I guess it comes down to where and how you ride. Here in Colorado I've never really had a problem overheating. I'm accustom to putting down my ice scratchers on the trail. The only time I've seen issues heating up was on a dirt road in the spring, but everyone was struggling.

Are you guys that want more cooling riding the trails a lot or is there another reason for the issues over heating? The third cooler seems helpful. It does add a little weight.

My biggest issue is when I break a scratcher on the trail and there's no place to hop off. It's also hard to keep it cool during spring time....

 

[mountainhorse]

I NEVER see the cooler as a hinderance...even with weight... when I tip on their sides the PRO RMK's I ride with and look at the at the front of the tunnel snow-exit... I see at least the weight of the cooler/coolant in ice "plaque" built up.

I do often see it as a help.

For the 2015 snowchecks... you can get a standard RMK with all the "PRO" bells and whistles except for the QuickDrive... which you can switch out to the C3 or TKI units for less than the diff.



.

 

[Rick!]

Good evening,





I've been reading about how much more effective the cooling system is on the standard RMK model over the Pro yet after examining the plumbing of the coolers on the standard model, I'm at a loss as to why?



It would appear that the front heat exchanger on the standard RMK would see maximum flow until the thermostat starts to open at which point the flow would begin to pass through the rear coolers. Given the logic that a fluid takes the path of least resistance it's surprising that the RMK doesn't actually run hotter as the coolant would favor the front cooler circuit over the rear when the thermostat is wide open? You'd think the cooling system would be more effective if all three coolers were plumbed in series?



One can't argue with the fact that the standard RMK runs cooler than the Pro, I just wish someone would explain how it's possible.

You'll notice that the fittings on each loop of the system are carefully sized to provide the right balance, or flow split between the loops. Couple that with each loop's flow resistance and the bottle collection point and large diameter WP inlet and the cooling done by each loop matches the engine heating very well. The regular RMK doesn't suffer from the the same issues as the Pro. IMO, the Doo or aftermarket stats are not necessary on the regular RMK.

 

[live to ride]

You'll notice that the fittings on each loop of the system are carefully sized to provide the right balance, or flow split between the loops. Couple that with each loop's flow resistance and the bottle collection point and large diameter WP inlet and the cooling done by each loop matches the engine heating very well. The regular RMK doesn't suffer from the the same issues as the Pro. IMO, the Doo or aftermarket stats are not necessary on the regular RMK.

this may be a silly ? but some have said that using a aftermarket stat to bring your temps down to 100-103, wouldn't that be just as bad running at 17-20 below as 30-40 above?

 

[TurboMatt]

I added a Van Amburg rear tunnel cooler and 110 deg thermostat for this season. It makes a HUGE difference. Thermostat propably wasn't needed, but I had it apart so I threw it in. The cooling issues are basically gone. My hyfax will melt off, before I have cooling issues now. I still use my scratches, but I have much more leway now in low speed of very low snow conditions.
Hell, I trail rode this thing in southern WI probably 150miles this year with no issues.LOL That wouldn't have been possible last year.