2021 RTL with coolant leak after riding with OK coolant temps all day! Anyone else? Any ideas?

[BobJ]

Arrived home after a 200 mile day at 90+ degrees. Coolant temp was normal all day. Parked in the garage. Next morning there was a big puddle of coolant on the floor. Checked the bottle, it was low. Started it up and moved it outside to clean up the floor. Let it run for a bit and the fans came on blowing forward. When the fans ran, it blew coolant out the front of the radiator. Anyone else have this problem?

Hose clamps, radiator, &/or water pump come to mind. Do I have to remove all the front plastic bodywork to diagnose? I am a decent mechanic. This is the first issue with this machine, which I bought new. Warranty is over, of course. Anyone with advice or had a similar issue? 22k miles on the bike. Thank you.

 

[Gwolf]

First and easiest to check is the cooling system pressure cap. There is two notches to tighten it down. First notch is about a half turn to get it aligned and started and then the second notch snugs it down to seal it for holding pressure. If it is not tightened down correctly it will vent coolant before it gets up to the correct temperature. If anyone at all has had the cap off for any reason, check that first for sure. Check it first anyway to be sure the leak is not just a pressure cap that is not holding pressure anymore. If you have a pressure cap tester use it, if you don't have one, any auto parts store should have a tester and most will test your cap for free. The correct pressure is stamped on top of the cap.

If the coolant blew out the front grill when the fans were blowing in reverse, then the leak would probably be somewhere on the components located around the frunk area (front storage hatch). Easy to remove the frunk door which only has a few torx screws on each side of the hinge to remove. You might want to put some alignment marks on each side so you get it in exactly the same place when you put it back on. The hinges are adjustable with slotted screw holes. Once you get the door out of the way, you can remove the Frunk liner. That leaves everything under the frunk cover open so you can see in there and hopefully find what is leaking. There are two radiators in there and the connections going back to the engine cooling jacket. You might not be able to fix what is wrong working through the frunk opening, but you will be able to see if the problem is in that area. If the problem is a leaking hose farther back, the fans could still be blowing the leaked coolant out the front, but you will still need to have the frunk area open to replace any hoses. If it is a radiator leak, you will be able to see it through the open frunk cover.

First job is finding the leak. It was not running hot and if it had been the overflow, it should have gone down the overflow hose when the cap vented, not blowing out the front by the fans. Whatever you find, there will be more body panels to remove before it can be fixed.