Coolant Leak

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What was the radiator coolant level when you first checked it way back at the beginning of this issue? Was the rad cap secure and in the proper position?

 
Before service, coolant was between the marks, and blue in color. After, bottle is full of a faint yellow green mix. Still almost to the top. Cap on overflow bottle on securely. The drip tube (the tube under the bike that dribbles a little when I park the bike) goes to the overflow bottle cap. Haven't checked any other cap yet.

Edited- I thought fans were supposed to kick on at 215. I see it's 225. If fan's kick on at 225, at what point does the display switch to "Hi"? Will try again. Not exactly good news. If they are kicking in, there's some other concern that made it overheat.

I'm interested in your thoughts. I am entirely confident the dealer shop caused this problem, but as you might understand, I'm reluctant to give them the bike.

Could air in the system result in a overfull coolant system that allows the bike to overheat?

 
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If the shop monkey added the coolant via the radiator cap, he probably didn't get it back on properly - simplest explanation. (Space is a little tight in there and it would be easy to screw it up.) The service manual (at least for Gen II) would have you remove the left side panel to access the radiator cap but you can get to it from above (opposite side from battery). I don't know enough about the Gen III to be any help here. As mentioned, if the problem is something more complicated than this, I would have it back to the dealer; especially if you aren't comfortable with digging into thermostats, temperature sensors etc.

 
And a loose rad cap would not cause leakage but could cause overheat? I can see the expansion tank lid, still looking for the rad cap...

Hoping for an easy fix. I consider it highly unlikely that the one day the bike is in for throttle body replacement, a part (on a 2014 with less than 35K) failed in that tiny window. Sabatoogee, perhaps, but I'm not buying random failure.

 
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Have been following this thread and can only sympathise with the trouble you've been having.

To my knowledge there would have been no need to disturb the cooling system for a throttle body change, I think early Gens did have a coolant pipe for the fast idle system.

I've searched my manuals (Haynes and Owners/FSM, 2013 Gen III) and can't find any reference to the temperature that 'Hi' comes on, all I know is that my fans kick in at 105 C (221 F) and it cools down immediately.

By the mixed colour of your coolant it sounds like the dealer has 'done you a favour' and topped it up with a different coolant. The rad cap could be on but not turned fully clockwise into the latched position, worth checking.

Not the best picture but this is the 'Rad cap' on a Gen III, it is actually on the thermostat housing. Not done it but I think it is accessed by removing the glove box panel, I had the fairing panels off anyway for a 12,000 mile service and fitting frame sliders/foot shields. I did a coolant change while I was at it and had no problems at all.

Cheers

Gary

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I think a loose radiator cap will not allow the coolant to pressurize. The coolant's boiling point is raised when it's pressure is raised. With a loose cap, the pressure of the coolant is basically atmospheric pressure, and the boiling point would be lower - and some coolant could boil out of the system.

But if that were the case, I think it would boil out of the loose cap. That's where the hottest coolant exist. Well I suppose technically, the hottest coolant is on the cylinder head side of the thermostat. But from there, it goes to the radiator via the upper radiator hose. The coolant is "cooled" through the radiator from the top down.

If the radiator cap is on tight, and you have no other leaks (a BIG if right now), then the system is getting pressurized. If the system is getting too hot (as you have indicated), then it gets overpressurized. That is what the overflow tube is for. The expanding boiling overpressurized coolant gets pushed to the plastic reservoir until it is full, where it is pushed out the overflow tube, which is where I think you are seeing the leak.

Which brings me to 1 of 4 conclusions:

1. There is air in the system that can't get "burped" out. Air takes up volume. When the coolant is drained, or otherwise the system is opened up, after it is refilled, gravity may not allow the coolant to find every nook and crannie within the system (especially in the radiator and the engine). For myself, I always fill the coolant and start the bike with the cap off. I allow the bike to come up to running temperature and usually the water pump will move the coolant and force the air to "burp" to the highest point (just like when you burp the CO2 from your beer - at the highest point!! LOL). I top off the coolant, then put the radiator cap on, then re-start the bike and allow the system to pressurize and the fans to cycle one time on and off. Then check for leaks and top off the reservoir.

2. The fans are not working as they should. As previously stated, they should come on at 225 and go off at 215. Just because the are working in DIAG mode may not mean they are coming on when they should. If the fans don't come on until past 225, and/or they shut off above 215, then you are overheating the coolant, and overpressurizing it. You can check this in your driveway idling the bike.

3. The thermostat is hanging closed or partially closed. The thermostat for the bike is designed to open at a specific temperature to allow coolant to circulate. If it is hanging closed (or even partially closed), then the coolant in the motor can't circulate and will over heat because it can't get to the radiator.

4. The temperature sensor is not working properly. The coolant temperature sensor is screwed into the cylinder head and I believe it is just before the thermostat. If this sensor is faulty (or perhaps has a loose wire), then the ECU doesn't get feedback and the bike can overheat. I'm sure that might have something to do with the fans too.

I make these suggestions assuming there are no coolant system leaks, as you have eluded to so far in this thread.

I hope this helps.

 
No leaks except for through the reservoir overflow tube, which technically isn't a leak. But I didn't know that at first. No steam or dripping anywhere, but I fancy I've smelled coolant a couple of times. And the few drops from the overflow tube wouldn't be enough for that. Bottle is still overfilled. Maybe an inch from the very top. Good info all.

 
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It's pointing toward the rad cap not being secure.

If it is on but not latched the pipe to the expansion tank would be open all the time.

Just popped out to my bike to see if I could get to the rad cap or even see it, nah!

In my photo the 'ears' of the cap are aligned fore and aft which I think is also in line with the short piece of plastic that the expansion tank pipe fits over.

It's not that difficult a job to take the glove box panel out to check the cap. If it is unlocked then the system level should be re-established.

 
Talked to the shop manager. He agreed that it doesn't make sense that something else stopped working while the bike was in getting the throttle bodies replaced. He doesn't believe a part went bad coincidentally during the warranty repair. I asked him to help me figure out who might have accidentally done what, and what they recommend to check. I explained that, on my initial call, only "couldn't have, wouldn't have, can't have" from the mechanic made it hard to figure out what happened. The baby jesus didn't add that extra coolant. I am far more likely to find the fix through you guys, but I'm exploring all options. Gary- going to try to get to the cap when I get home, if I get home early enough. At least now I know where it is.

I am hoping that the loose cap is it. If I understand correctly, it is possible that the loose cap could cause coolant to divert to the overflow tank, which could create both the symptoms I am seeing- overheat when sitting, and an overfull expansion tank (?). Could it be as simple as a cap got bumped or incompletely reinstalled during the TB replacement?

I've pulled the panel off on the battery side (did it when I got it home to ensure I could get to the battery quickly in a pinch). No big deal. Will have to look to see what is involved to get to the left side.

We shall see. Thanks again.

 
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Cool, left panel is the same but there is wiring to the 12V outlet, should be enough slack not to need unplugging it.

I think you may have to pop the glove box lid with the ignition on to get to a screw under it.

Yamaha call the plastic tank a coolant reservoir and not an expansion tank which is interesting, trying to get my head around how it works exactly.

Don't drop any of those little plastic pop fasteners!!!

 
I could be wrong but I don't believe coolant can move from the expansion tank back to the radiator if the radiator cap isn't installed correctly.

There won't be a vacuum to move the fluid back.

You can probably verify if the cap is installed correctly by simply running the engine until the fans start and then shutting the engine off.

There should be a movement of hot coolant from the radiator to the expansion tank. And then as the liquid cools you should see the coolant migrate from the tank back to the radiator.

 
You have to do the basics first, otherwise this discussion is not going anywhere. I can't understand why you didn't remove the excess from the reservoir to prevent puking, which is a natural symptom if it's overfilled too far. Also, just because the display says "Hi" doesn't necessarily mean it overheated, and I'll bet the coolant never boiled (properly filled, rad cap on properly and in working order, the boiling point of 50-50 coolant is 265 F). There is no reason for a low mileage '14 to have a cooling system problem, and I can't recall anyone with an FJR having a thermostat stuck shut (although it is possible). But, get the basics done, see if your 'problem' goes away.

 
Puking isn't a troublesome symptom, given where it's coming from. It was alarming until I figured out the source. That's why I haven't pulled the overfill. Once I figure out why it went to Hi, whether that's a loose cap or a loose connector, I can worry about more aesthetic issues.

Agreed Ray. The second it went to "hi" I got it in the wind and then parked it while I went in the store. So it wasn't "hi" except for the briefest of times. Will report findings if I can get to the cap.

 
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Got the basics done. Problem didn't "go away". Checked cap. In place properly. No sign of leakage. Removed cap and ran it for a bit covered. Replaced cap. Ran bike in garage. Bike slowly climbs in temp. Fans kick on at 220. But temp slowly continued to rise. Shut it down at 230. Crawled under and around looking for kinks or loose clamps. It's got plenty of coolant and runs great. You just have to shut it down if you're stopped for over a minute or two. The irony. That's why I didn't buy an air cooled bike or retain my oil cooled bike. At least I learned how to pull it apart to see the radiator cap and put it back together.

 
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Update- talked to shop again. Then I called Yamaha corporate. Told them shop is super concerned and want to help, but maintain that they could not have been in any way involved in the magically appearing heat issue. Must have been the new Yamaha part or a spontaneous bike issue that appeared during the two hours they had it to put on the long awaited throttle bodies. Yamaha corporate dude said that's not reasonable at all, clearly related to the warranty repair. They'll call dealer, and ask for preferential scheduling to fix. I'm going to my aircraft carrier sized deck to drink a beer and catch up on today's mail, which, all in one day, included American Rifleman, BMW MOA, and MCN. Merica.

 
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I assume you are absolutely sure that the cap is on properly and fully tightened? - it sort of locks in place and hits a hard stop. (I thought that this was the most likely problem) The only other thing I can think of is the thermostat (assuming there are no restricted hoses and the radiator isn't air locked at this point). Thermostat problems are not common. Sounds like it is time for the dealer to get to it!

 
I thought the same Ross. I was more than hopeful it was the cap. I was confident... But cap is good. No mushiness or orientation issues. It's on on like donkey kong. Can't imagine what's up. But Yamaha says that's BS and has to be related to warranty repair, and dealer says it couldn't have been them but they want to make it right. So you can maybe see why I associated the current problem with the former one by involving Yamaha.

 
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Curioser and curioser

My original 2013 coolant colour was blue, if yours has changed colour then somebody has added something different.

Castrol Radicool is blue BTW, not sure if that is available in the States, seems to do an overly good job.

Could it be that they've pulled the coolant hoses off of the cylinder head in error and then had to top it up?

Can't see how they could get that wrong even if they had done it.

The rad cap can be pressure tested but I've never heard of one failing.

Keep us posted.

 
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