Coolant Leak

[Gary B]

Don't want to be a doom monger but I've had a horrible thought.

Could the fuel mixture be too lean with the new throttle bodies, making the engine overheat?

We don't have YES in the UK, does 'tinkering' with the bike invalidate the warranty?

 

[RossKean]

^^^

No. Computer controls the mix.

For "tinkering" to invalidate the warranty, it would have to be shown that what you did caused damage. Or that you did not follow required maintenance procedures (oil changes etc.). The burden of proof would be on them although you need to maintain adequate records on maintenance you do for yourself.

 

[Gary B]

Cool, I'm just a little bit paranoid because I also own a Gen III FJR, so far (touch wood!) it's been faultless.

I've had one fuel injected car (also faultless) and this is my first fuel injected bike, just need to trust ECUs more!

When I was service manager in a Yam/Suzuki dealer we made it very clear at handover that 'tinkering' (usually de-restriction without re-jetting) would invalidate any warranty (statutory one year) and we had to fight many cases of damaged engines caused by 'bodge jobs'.

I'm going off at a tangent because that's not the problem here but just wary that Bill doesn't do anything after suggestions from the forum that the dealer could get upset about.

A friend just got a a new Triumph Explorer after 600 miles (cylinder liner water seal failure), the company were very good.

This case is quite unusual, out of the 'big four' Japanese makers Yamaha gets my vote for reliability.

 

[Bill Lumberg]

I wouldn't tinker. But I'm glad to have tried the things suggested here regarding the cap. I talked to Yamaha and made it clear that the bike was not good. Rep agreed it was obviously a result of the warranty work paid for my Yamaha, whether a shop mistake or whatever. I wanted to tie the overheat problem to the repair officially, and for Yamaha to be involved in the fix, rather than just the shop. More incentive. With just the shop involved, too easy for them to blame something random, or to say it's not warranty related and try to charge me. When I initially called the shop to report the problem, the mechanic indicated it must be a part failing. Couldn't be related to repair. Bike stopped dribbling as soon as the reservoir got a little room in it. Seems to take a little longer to warm up from Lo to numbers at idle, and runs a little warmer in traffic, even though it only overheats at a stop. On a cool morning, during an interstate run, I was averaging low to mid 100's temps at speed. Now I'm running 165-175. All relative depending upon ambient temps, of course. No remaining symptoms except overheat when stationary. Fans kick on and run great, but the bike acts as if they never kicked on.

 

[RossKean]

Bill, at this point I think you should turn it over to Yamaha for diagnosis and repair - especially if it is on their dime (and they can promise it won't take another month or more). The coolant puke may have been nothing more than an overfill. The apparent overheat may have been due to air in the system (rad needs for be "burped"). There could be an issue with the opening temperature of the thermostat as well. I guess they could check the water pump for flow rate as well but if it isn't leaking I haven't heard of other problems with them. Hell, maybe it's nothing more than a temperature sensor reading a bit too high making you think it is overheating. In the interim, I don't think I would worry about riding it - just keep an eye on temps.

Anyway, once you have done the very basics (rad cap and hose kink), let them deal with it. I am very familiar and comfortable with doing mechanical/electronic diagnosis on my bike and would probably dig into it further myself. On the other hand, I don't have any sort of warranty coverage and have no other bike to ride while the dealer messes with it.

Hope they get it fixed for you soon.

 

[Constant Mesh]

Seems like the coolant flow rate is too low.

The two obvious devices which can affect flow are the thermostat and the water pump.

The thermostat should be fully closed until the temp rises to 160 deg F. As the temp rises the thermostatic valve opens more until it's fully open at 185 deg F.

If the fans can't bring the temp down that would suggest the coolant flow through the radiator is not adequate for that operating condition.

 

[Bill Lumberg]

Smells like warranty... Hopefully we won't have to wait for gojira to gestate a water pump over 90 days like we did for the throttle bodies.

 

[wheatonFJR]

Mothra is your man on this one.

 

[hppants]

Well it just sucks that you are going through this. I hope Momma Yamaha will "encourage" your dealer to fix it, and fix it quickly. I suppose one consolation is that the problem is easily presented. It's not an intermittent thing. If they decide to throw parts at it, they will know quickly if it's fixed.

Seems like a pretty straightforward diagnosis. Pressurize the cooling system and verify no leaks. Verify the temp. sensor is working normally. Verify the fans working normally. Then replace the thermostat. Then replace the water pump (if necessary).

I've disassembled a Gen I water pump and if the Gen III W/P is the same construction, there is NO way that is the problem. That metal impeller will pump water for a million miles.

still subscribed....

 

[Bill Lumberg]

Just super unlikely for the bike to randomly develop this problem, part failure or not, accompanied by a full-to-overflowing overflow jug, all in tiny time span during a throttle body assembly replacement.

 

[Viper Pilot]

I think your allergic to RED!

 

[Bill Lumberg]

Interesting bullshit. Overflow tank is no longer filled to the brim with nearly clear stuff. It's between the full and low marks and it's now green like the coolant in the radiator. Tip top and clearish for days. Now looks fairly normal. Been having to have my son rock the bike every day so I could see the full level of the clear stuff. Mfer still skyrockets temp wise if it's sitting.

 

[RossKean]

OK, how about this?

Your radiator may have been air locked. Fluid got heated up and some hot air or steam blew out into the overflow tank - excess fluid puked onto the ground. The top-up the guy did at the dealers was just water (probably not even distilled water) and was just added to the overflow tank. After a few heat cycles, the air got blown out of the radiator and fluid (mostly water) got sucked back into the radiator when it cooled down. This mixed with the normal green stuff. On the next heat cycle, the mixed coolant did what it is supposed to do - go out to the expansion tank as it heats up. After a couple more cycles, the fluid is almost the normal color (some gets exchanged each cycle) - probably slightly diluted by whatever the guy put in there.

Maybe...

Try another run. You might find it is OK now after a few cycles (or there may still be air in it).

Or, just take it back to the dealer and let them figure it out. Judging from their decision to replace the entire throttle body when the issue was likely a TPS, maybe they'll replace the entire cooling system!

I suspect you don't have a major problem at this point. Maybe some air still in the rad. Less likely but still possible would be faulty rad cap, thermostat or temperature sensor. Maybe even a kinked hose. Far less likely to be a bad water pump.

I just want this all to be over and have your bike working right!!!

 

[dcarver]

I chased an air bubble on the KZ1300 for weeks. Turns out the the ONLY way to purge it is raise the front as high as possible to allow the bubble to rise up and escape from the block. Just another data point....

 

[Bill Lumberg]

Thank you. Once my daily check revealed a surprising return to normal levels and colors, of course I had to see if it still overheated. It did, definitively. Tracking all data points and suggestions. Looking forward to being one more boring example of high miles and no problems.

 

[Bill Lumberg]

Definitely continues to run at a higher, but not troublesome, temp. Even on this cool morning. Would love for it to self resolve. Waiting on word back from Yamaha before taking it in. Carver- how did you raise the font end? Did you do it while it was running?

 

[RossKean]

The front end raising was on his Kawasaki KZ1300, I believe.

 

[Constant Mesh]

On the Gen 1 the high temp blinking indication begins at 248 deg F. The fan starts at 221 deg F. I'd imagine the temp rises a bit more before the fan has an effect but I don't believe the temp ever exceeds 230 deg F with the fan on.

You mentioned that the level has dropped in the reservoir. That verifies that air was in the system and some or all escaped via the radiator cap and reservoir as it should.

Looking at the layout of the cooling system it appears that the only location where air might be trapped temporarily is in the piping just above the engine where the temp sensor is located. Coolant exits this assembly on the left side on its way to the thermostat and radiator.

If a small quantity of air is trapped in this location you might help it out by tilting the bike over to the right as far as possible while it's running with the thermostat open -- temp above 160 deg F. You need coolant flow to move the air so the thermostat must be partially open.

I'd imagine the Gen 2 and later are more sensitive to air in the system since they have less coolant than the Gen 1.

The Gen 1 has 3.4 quarts. The others have 2.75 quarts.

Your shop techs will get it sorted eventually.

 

[Fred W]

Bill,

If I am understanding the situation, you are saying that the bike is "over heating" because the temp display is saying "Hi", correct? It is not barfing coolant yet, just displaying "Hi" warning?

And, when you are testing it you also say the fans are kicking on at the right temp, and blowing air through the radiator properly (from front to back), correct?

If the engine temperature is being properly maintained at normal levels while riding the bike, and 165-175 are normal levels AFAIK, then this means the thermostat is operating correctly, the water pump is moving coolant properly and the radiator is shedding the coolant heat correctly.

You've said the fan is kicking on and blowing hard, so that should cause the coolant temp to drop a short time after it does kick on, but you say that the temp keeps climbing then, which gets back to the fan not blowing enough air or the radiator not shedding enough heat.

I think that the change in coolant color indicates that the shop is pulling your chain here. Something happened while they had the bike and they are not telling you about it. You weren't supposed to notice that. Wonder what kind of shit is they put in there? Might be worth doing a drain flush and fill with a known quality coolant. I'd do that before I ever set foot back inside of that shop if it were me.

 

[Bill Lumberg]

Not the first time the shop has told me straight up that something didn't happen, couldn't have happened, when it was clear as day it happened. I know, I know. But I've been trying to complete the process with this warranty/dealer issue in a linear fashion. I've considered getting a coolant change done elsewhere to see if the problem resolves.