Coolant Overflow

[FinalImpact]

Notice the radiator has two distinct sealing lands. The outer keeps the complete system from letting coolant out and letting air in. The inner landing
should be inspected for debris or damage. If paint, rust, some form of debris is keeping the cap from making a good seal it can spew over before reaching pressure.

Also a visual inspection of the cap may reveal a gouge, cut, debris stuck to the rubber that prevents the inner land from sealing. That includes the valve built into the cap. Pull it down and inspect for debris.

Here are a couple of pictures; next time its cool inspect the inner landing for any flaws. A simple chunk of debris on this landing can lead to venting before set pressure is reached. Also, it prevent it from refilling as the engine cools which ultimately leads to it pushing water out as it has MORE ROOM FOR STEAM. Once the block makes steam inside it tends to push more and more water out.

Back to the inner landing: As the engine heats the coolant expands and goes past the inner landing into the coolant overflow container. This is normal. So that inner landing lifts and lets engine coolant out at 16 psi (caps rated pressure). Once the engine is off and cool down begins, the coolant in the block contracts. Here is is where that little disc in the Radiator cap comes into play, vacuum internal to the blocks coolant system pulls it open and s u c k s fluid back into the block.

So, if the inner landing is flawed, that throws a wrench in the hole process. Also if the tube in the overflow tank has a leak it won't pull the fluid from the bottom of the tank. Instead it just sucks air.

Confirm the inner landing is good.
Confirm the flapper on the cap has no debris in it.
Confirm the tube from the neck to the tank has no holes in it and it reaches the tanks bottom.

View attachment 49157 View attachment 49158

 

[RideFz6Style]

Here are a couple of pictures; next time its cool inspect the inner landing for any flaws. A simple chunk of debris on this landing can lead to venting before set pressure is reached. Also, it prevent it from refilling as the engine cools which ultimately leads to it pushing water out as it has MORE ROOM FOR STEAM. Once the block makes steam inside it tends to push more and more water out.

Back to the inner landing: As the engine heats the coolant expands and goes past the inner landing into the coolant overflow container. This is normal. So that inner landing lifts and lets engine coolant out at 16 psi (caps rated pressure). Once the engine is off and cool down begins, the coolant in the block contracts. Here is is where that little disc in the Radiator cap comes into play, vacuum internal to the blocks coolant system pulls it open and s u c k s fluid back into the block.

So, if the inner landing is flawed, that throws a wrench in the hole process. Also if the tube in the overflow tank has a leak it won't pull the fluid from the bottom of the tank. Instead it just sucks air.

Confirm the inner landing is good.
Confirm the flapper on the cap has no debris in it.
Confirm the tube from the neck to the tank has no holes in it and it reaches the tanks bottom.

View attachment 49157 View attachment 49158

Thanks for the advice. I am currently away from my bike until Saturday so I will not be able to confirm anything until then. But, seeing as it is a brand new cap I expect the flapper is in good condition, so I will be sure to check the inner landing for any small debris as well as the hose for leaks.

 

[FinalImpact]

Thanks for the advice. I am currently away from my bike until Saturday so I will not be able to confirm anything until then. But, seeing as it is a brand new cap I expect the flapper is in good condition, so I will be sure to check the inner landing for any small debris as well as the hose for leaks.

All it has to do is suck chunks from the tank or block and a new cap can suffer the same fate. Perhaps a flush is in order. Curious; you have any means of checking the temperature like an AC thermometer, Laser Thermometer, Thermocouple to hand held meter???

 

[RideFz6Style]

I did do a full flush recently, like two weeks ago(no metal bits or anything were in the flush). I do have an infared thermometer somewhere around the house(won't be home till Saturday though). What should I check temperature on?

 

[Motogiro]

Randy makes a good point on that cap washer sealing on the seat of the fill neck on the radiator. It could have a piece of junk on the seat.

I know you guys are close to solving this but I also just thought of a possibility.

When the bike was flushed and you replaced the coolant was it already a 50/50 mix? The closer you come to high percentage water mix the higher the pressure will be in the cooling system which would create greater expansion. What coolant did you refill with? Are you sure you're running a 50/50 mix?

Another long shot but a possibility is could the overflow res have the hoses reversed? They probably are not interchangeable but remember we're trying to troubleshoot from cyberspace and I don't have the FZ6 anymore..

Another member here had this problem on his Speed Triple and it was a known defect that is popular with that bike. He replaced his cap and it was good to go. When we stopped it pissed out coolant...

 

[RideFz6Style]

Randy makes a good point on that cap washer sealing on the seat of the fill neck on the radiator. It could have a piece of junk on the seat.

I know you guys are close to solving this but I also just thought of a possibility.

When the bike was flushed and you replaced the coolant was it already a 50/50 mix? The closer you come to high percentage water mix the higher the pressure will be in the cooling system which would create greater expansion. What coolant did you refill with? Are you sure you're running a 50/50 mix?

Another long shot but a possibility is could the overflow res have the hoses reversed? They probably are not interchangeable but remember we're trying to troubleshoot from cyberspace and I don't have the FZ6 anymore..

Another member here had this problem on his Speed Triple and it was a known defect that is popular with that bike. He replaced his cap and it was good to go. When we stopped it pissed out coolant...

I replaced with the Prestone premixed(50/50) extended life coolant for aluminum engines. As for the junk on the inner cap seat..I will definitly be taking a very close look at that to ensure nothing is on there. And like I said, any help is appriciated because any small hint could be the solution(so no worries there)!

 

[FinalImpact]

Randy makes a good point on that cap washer sealing on the seat of the fill neck on the radiator. It could have a piece of junk on the seat.

I know you guys are close to solving this but I also just thought of a possibility.

When the bike was flushed and you replaced the coolant was it already a 50/50 mix? The closer you come to high percentage water mix the higher the pressure will be in the cooling system which would create greater expansion. What coolant did you refill with? Are you sure you're running a 50/50 mix?

Another long shot but a possibility is could the overflow res have the hoses reversed? They probably are not interchangeable but remember we're trying to troubleshoot from cyberspace and I don't have the FZ6 anymore..

Another member here had this problem on his Speed Triple and it was a known defect that is popular with that bike. He replaced his cap and it was good to go. When we stopped it pissed out coolant...

Not easy to swap but possible I suppose! Almost brought that up, but I blab too much as it is.... lol

 

[sandctrev]

I was having the same issue, thought I fixed it. I no longer have a leak or spray comming from the same area. But I have temps on average of 190 and reaching 205 while riding up to Julian yesturday.

Oh when I had flushed it came out almost black.

 

[FinalImpact]

FWIW: mine is an 08 and I've done the coolant once and would guess it's never been done prior. In ambient temps of 75 or so it runs on the stat at 165 ~ 175 at speeds over 35mph.

If stopped in traffic for 5 min on an 85F day, it climbs to 205F and fan comes on then cools down as soon as I start moving ~185 ~ 195. If parked for longer, fan cycles kicking on and off but rarely hits 212.

Yesterday it was 90F and while going up the Mt at 60 ~ 70 mph, temps were 182F. On the way down at same speeds (no load), reported temp was 162F lol

With your infrared thermo:
1) read the left side tank and the ride side tank. Its a cross flow radiator so the Engines heat will be in the LEFT tank and the Right tank should be cooler.
2) under the throttle Bodies is the thermostat outlet. It should report the engines temp at the meter. Do they AGREE?
3) Some oils will raise the blocks temp, grab a reading from the pan area too.
4) grab stuff with your hands and get a feel for how long you can hold it so you know its condition when no other means of measuring is handy << haha!

 

[TownsendsFJR1300]

I know you did do a flush (and the previous fluid was nasty). If you just refilled with 50/50, it may still be somewhat slightly diluted.

Its cheap enough (you likely still have enough in the jug) and easy enough to pull the lower hose, dump it, and put in fresh coolant, just to cover the basic's.


Note, the Op's bike is an 07 as is mine so the below added info may help:

Cliff, the rubber overflow cap has two outlets.

There is a tab (to grab and pull off) that faces outward with a rubber hose that goes up and around the cam chain cover (has to tie into the coolant system). Also on the cap (facing inside) is another nipple, a bit larger, that reduces down, a hose connects to that and dumps the overflow fluid about 5" straight down from there...


*Randy's temps are right in line with mine as well...

 

[RideFz6Style]

FWIW: mine is an 08 and I've done the coolant once and would guess it's never been done prior. In ambient temps of 75 or so it runs on the stat at 165 ~ 175 at speeds over 35mph.

If stopped in traffic for 5 min on an 85F day, it climbs to 205F and fan comes on then cools down as soon as I start moving ~185 ~ 195. If parked for longer, fan cycles kicking on and off but rarely hits 212.

Yesterday it was 90F and while going up the Mt at 60 ~ 70 mph, temps were 182F. On the way down at same speeds (no load), reported temp was 162F lol

With your infrared thermo:
1) read the left side tank and the ride side tank. Its a cross flow radiator so the Engines heat will be in the LEFT tank and the Right tank should be cooler.
2) under the throttle Bodies is the thermostat outlet. It should report the engines temp at the meter. Do they AGREE?
3) Some oils will raise the blocks temp, grab a reading from the pan area too.
4) grab stuff with your hands and get a feel for how long you can hold it so you know its condition when no other means of measuring is handy << haha!

Well while we wait for Saturday to roll around I can atleast say I agree with the temps given. Riding around in 80 degree weather at speeds reads around 170 at the gauge. When stopping at a light or traffic it can bump to around 200 but then cools back down to 180's when riding again. If it hits above 212 the fan always kicks on and cools back down to 200. So that's a good sign atleast.

 

[TownsendsFJR1300]

Well while we wait for Saturday to roll around I can atleast say I agree with the temps given. Riding around in 80 degree weather at speeds reads around 170 at the gauge. When stopping at a light or traffic it can bump to around 200 but then cools back down to 180's when riding again. If it hits above 212 the fan always kicks on and cools back down to 200. So that's a good sign atleast.

So did you determine what the actual fix/ issue was or just a combination of different things?

 

[pookamatic]

FWIW: mine is an 08 and I've done the coolant once and would guess it's never been done prior. In ambient temps of 75 or so it runs on the stat at 165 ~ 175 at speeds over 35mph.

If stopped in traffic for 5 min on an 85F day, it climbs to 205F and fan comes on then cools down as soon as I start moving ~185 ~ 195. If parked for longer, fan cycles kicking on and off but rarely hits 212.

Yesterday it was 90F and while going up the Mt at 60 ~ 70 mph, temps were 182F. On the way down at same speeds (no load), reported temp was 162F lol

With your infrared thermo:
1) read the left side tank and the ride side tank. Its a cross flow radiator so the Engines heat will be in the LEFT tank and the Right tank should be cooler.
2) under the throttle Bodies is the thermostat outlet. It should report the engines temp at the meter. Do they AGREE?
3) Some oils will raise the blocks temp, grab a reading from the pan area too.
4) grab stuff with your hands and get a feel for how long you can hold it so you know its condition when no other means of measuring is handy << haha!

Your bike definitely runs cooler than mine. When you say "flush" do mean that you used a detergent/solution? My "flush" was just distilled water, idling up to ~200, then replace with Prestone 50/50. Perhaps the cooling system has some scaling inside that is reducing the effectiveness.

It's also weird that your fan comes on at 205. Mine doesn't come on until 212. Takes only ~3 minutes to reach this temp from 180 once stopped in 85-90 ambient.

 

[pookamatic]

Also to the OP, I'm leaning towards a bad seating issue of the cap. But it can't hurt to take the new cap (and old if you still have it) to Autozone and borrow their tester. Just do it in the store... no need to leave a deposit.

 

[RideFz6Style]

So did you determine what the actual fix/ issue was or just a combination of different things?

Well rode twice this weekend, once at night and once during the day, both about an hour long..and there was no coolant pissed out of the hose:rockon:. I checked the cap when I got home and everything looked good and I wiped up the edge of the inner seal because there were a few little black particles there(dont think they were enough to cause it but maybe)..reseated the cap and added a little more coolant and had no overflow. Took temps of block(216) after ride and right at thermostat(195) which is what it was reading at the gauge. So for right now I will call it fixed, and we will see if this post gets bumped becaseit happens again.:thumbup:

 

[FinalImpact]

Your bike definitely runs cooler than mine. When you say "flush" do mean that you used a detergent/solution? My "flush" was just distilled water, idling up to ~200, then replace with Prestone 50/50. Perhaps the cooling system has some scaling inside that is reducing the effectiveness.

It's also weird that your fan comes on at 205. Mine doesn't come on until 212. Takes only ~3 minutes to reach this temp from 180 once stopped in 85-90 ambient.

Coulda been a brain fart on the FAN Temp - Honestly I think it is 212F when it pops on. This past weekend was insane torture to the bike. Sustained 95mph for 35" in 94F temps, bike read 182F. Not that I would admit it, but it was abused more than that climbing the pass out of Wamic to Mt Hood. Temps were hotter outside bike stayed at 182F.

No, no power flush or garden hose to the block. Just rip around town and drain it. Mine Looked like new when I dumped and it was likely there just shy of 4 years.

 

[seanalan329]

This just happened to me yesterday. Now this morning it was spewing from my radiator cap. I have a 70 mile commute to work and it is about 65°f outside. Yesterday after reading this post I did take a look at my cap and may not have put in right. I'll be doing a flash this weekend. Anyone know a good link for a walk thru?

 

[TownsendsFJR1300]

This just happened to me yesterday. Now this morning it was spewing from my radiator cap. I have a 70 mile commute to work and it is about 65°f outside. Yesterday after reading this post I did take a look at my cap and may not have put in right. I'll be doing a flash this weekend. Anyone know a good link for a walk thru?

Very easy.

On a cold engine, remove the small bolt on the RS of the engine at the water pump (where the large hose goes into).

***You can also, just remove the hose from the lower housing (messy but the possibilities of stripping or having leaks at that little bolt are eliminated).

Flush it with clean water if what came out is nasty. (I didn't flush mine as it was very clean when I last changed it). Pour or suck the fluid out of the over flow tank and flush (if need be). Note, a turkey baster is said to work well.

Clean the cap and the radiator opening as well.

Install anti-freeze thru the radiator (while on the side stand) and then the overflow tank (on the CC for an accurate reading). (I use Prestone pre-mixed 50/50, so there's no messing up the %'s)

Re-install the cap, go for a ride and get her hot, then let it cool down. Re-check the fluid levels and add accordingly.


NOTE: pay attention as to how the bolt / retainer attached to the radiator cap too.

 

[MG-242]

I recently replaced the water pump on our Ninja 250 - long story in itself. In the shop manual I think I remember it saying that if you see black debris, to flush the system with distilled water and a couple of tablespoons of vinegar. If I remember, I'll look at the manual tonight to confirm. Has anyone else heard of the vinegar\flush method?