About 700 miles ago, my RGU puked up it's coolant. Took it in and the dealer replaced the heat sensor and the thermostat and all seemed okay until today. Today, after a brief stop, I noticed about a quarter cup of coolant had leaked onto the ground. Checked the coolant level and it looked fine, as it has since they replaced the thermostat. So, is this a sign the new thermostat has crapped out ? How can the coolant level still look good when some had purged? Thinking I should have gone with the air cooled engine...

 

Looks like you might need another dealer visit.
I'd be leery about losing fluid in a liquid cooled Rushmore.

 

The Coolant in a Cooling System will expand and contract with temperature. Also, the change in engine temperature and the temperatures of all of the component parts of a Cooling System will change the amount of space available for the Coolant.

For both reasons you will find that a Coolant Recovery Tank has Two Levels: One for when the Coolant and the Engine are at Ambient Temperature (Cold) and one for when they are both at Operating Temperature (Hot).

I would suggest that you check the Coolant Level when the Engine and the Coolant are at Ambient Temperature (~6 hours of not running).

The Coolant Level should be at or slightly above the "Cold" Line. If it is; the Coolant you lost was probably because the Technician over filled your Cooling System when it was last worked on. Once you rode the bike and then let it heat soak after turning it off; the level of the Coolant may have risen over the top of the Coolant Recovery Tank and spilled onto the ground. In which case there is nothing to worry about . . . other than the competency of the person who worked on your bike.

On the other hand; if the Coolant Level is below the "Cold" Line when everything is at Ambient Temperature, you should return to the Dealer. The number of things that could cause this are far to numerous to pursue on a Forum such as this.

 

Check for codes. Turn your ignition on then roll your throttle to half way and hold it, the fans and pump will come on. Feel for air coming out the side of each radiator and then feel the cover on the pump to see if you can feel it running.

 

Did the roll on the throttle trick and yes, the fans both come on and the pump feels like it is working. Cold, the coolant level is slightly below the line. Previously, it had been right at the line. Which makes sense because only about a quarter cup of fluid purged. I'll ride it a bit harder this weekend and see what happens. I'm a little more nervous about this than I would normally be as a week from tomorrow (Wednesday) I leave for a 1,500 mile trip and will be in some remote areas. Sure would hate to have an issue out there.

 

The Rushmore wet-head is still an air cooled engine.


Put a small container of coolant in the saddlebag for a warm fuzzy and enjoy your ride.

 

I have the exact same problem. Please keep us up dated as to how this works out for you.
Jonnierock

 

LOL...I carried around a quart of coolant (fit very nicely in the saddle bag) for months when I got my '14, eventually got confident enough to take it out. Topped off the coolant once (maybe year and a half ago) and none since then. All good...

 

I had to laugh at myself when I was replying to RT. I had (not sure if I still am yet) having the same problem. My '14 discharged coolant last weekend. It looked like a lot on the ground and the reservoir was empty. Naturally, I'm headed to Arkansas on Sat morning for a weeks worth of riding. The dealer didn't give me any useful info and I didn't want to chance them not having it ready by Fri afternoon. The pint container looked so small, so I sprung for the 1-gallon of coolant. I twisted off the filler cap on the neck and started pouring. I would be surprised if I got 2 oz in the system before it was topped off and dripping all over the lower. Twisted the throttle to run the system for about 10 mins. No air.....change in the level. Filled up the reservoir and took it out for a spin. No change. Guess I will see what happens on Sat morning. But, I'm taking a small container of coolant in the saddlebag for a warm fuzzy.

 

I probably should have checked sooner (2015 Limited , 11K miles now) ............. but with all the recent discussion here, I performed my first coolant level check since having my water pump replaced back in early August (approx 9K miles). (I know - should have checked long ago.)

I was kinda surprised to see the level quite low - could just see a little coolant in the overflow tank. I dont see/smell any leaks. I'm hoping its low because of some air in the system, going back to the coolant being refilled when the pump was repaired in August.

So I bought the 16 oz coolant container from HD, mainly because it will be a handy size to carry in the saddlebag. And based on the fact that it took all of 1.5 oz to bring it up to the coolant level marker, I hope it lasts me a long time.