Is it overheating or is it me?

[Marcin]

Today, when I came home from work (quite sunny and hot, about 27 C in shade) I parked my bike and got off it to open the gate. I heard the fan on the radiator but when I looked at the speedo I saw that the temp indicator was full, to the very top. It scared me a little because what I did was a short 7km ride in the city, no hard pushing, ordinary ride and this happened.

I had my coolant changed recently so the coolant is fresh. My question is - maybe there is some air in the system? Should the rubber hoses going to and from the radiator be stiff or should they allow me to squeeze them? Because, with the engine running, and the fan running as well, I could quite easily squeeze all three of them.

And another question - does FZ6 indicate that it's overheated somehow? Some blinking on the speedo or something?

 

[redballs]

I get a red light on my dash if mine overheats (08 Fz6). I believe it flashes also once it reaches a certain temp. Did you actually see the fan spinning (check for resistance or obstructions)?

 

[Marcin]

Thanks, but you've got the other dashboard so it won't work for mine

 

[redballs]

Thanks, but you've got the other dashboard so it won't work for mine

Sorry, I wish I could help more, but more information will definitely help one of the others to help more efficiently.
Try idling the bike and seeing at what indication bar the fan actually turns on, or try a laser thermometer and report back.

 

[Kingwu]

I get a red light on my dash if mine overheats (08 Fz6). I believe it flashes also once it reaches a certain temp. Did you actually see the fan spinning (check for resistance or obstructions)?

Does that happen to all Fz6's? I have an 07, and it says my bike is at 214+ degrees sometimes. Idk if that's normal

 

[Marcin]

My fan starts with the 5th bar ON (one before the final bar) on the temp display.

Last year I had also worries as my fan used to start quite often. Then I was assured that this is typical for this bike. However last year my temp indicator never reached the top. Still, if it overheats then the indicator is supposed to flash to warn me so I quess as for now I just ride and pay attention to what is going on there.

What about the hoses? Should they be stiff or soft?

 

[payneib]

Thanks, but you've got the other dashboard so it won't work for mine

I'm on the old dash. I've asked a couple of times for some more in depth knowledge on our temp gauge, but it seems to quiet when I do.

A few things I've noticed:
My fan kicks in at "four blobs" and rising (it freaked me out the other day when I stopped for petrol and it didn't come on with four when I turned the ignition back on, but once I started the bike it dropped back to three).
It takes a good 18 Celsius day, and no air flowing over the radiator (stuck in traffic, slow town riding) to get to four blobs.
The bike will run at two or three blobs on cold mornings (I didn't see the third blob between November and April).
I've only just started taking the liners out of my kit, and only just started hitting four. As theres only five, and it's going to get hotter, I can only assume I'll see five, and that this is fine.
If the bike does overheat, I'd expect to see an engine warning light and something like a flashing temp gauge.

Your best bet is to make sure your fan never jams (they can collect stones apparently) if you're stuck in a city, or better yet, get on some open road and get some air flowing through the radiator.

Sorry I can't help more.

Sent from my D5503 using Tapatalk

 

[FIZZER6]

The hoses should be stiff with the bike hot and running!

If you can squeeze them more than maybe 1cm something is wrong. I have a 2006 as well and never had the temp go over 4 bars even in 105F humid heat!

 

[Marcin]

How do you bleed the system? And what do you mean 'hot' - when the fan comes on?

 

[redballs]

Does that happen to all Fz6's? I have an 07, and it says my bike is at 214+ degrees sometimes. Idk if that's normal

My fan usually will turn on at the 212 mark, 214 is not to far of a discrepancy. It drops once it reaches that point if the cooling system is working correctly.

My fan starts with the 5th bar ON (one before the final bar) on the temp display.

Last year I had also worries as my fan used to start quite often. Then I was assured that this is typical for this bike. However last year my temp indicator never reached the top. Still, if it overheats then the indicator is supposed to flash to warn me so I quess as for now I just ride and pay attention to what is going on there.

What about the hoses? Should they be stiff or soft?

Hoses should feel stiff but not rock stiff.
My fan quit on me two years ago, but it would still turn on sporadically.
If you could find a wiring diagram of the circuits that control the fan and have a ohmmeter you could ensure it was actually functioning properly. I suggest this because the 5th bar from my research appears to be a bit late for the fan to start functioning.

 

[payneib]

How do you bleed the system? And what do you mean 'hot' - when the fan comes on?

Run up to temperature I'd say: two or three blobs. I'm not sure how to bleed it. I'd have thought you could probably get away with just rocking the bike from side to side if it's not to bad, just work the air out of any dead legs, then top up as before.

As a side, are you counting the bottom marker, the one that's on regardless? Might explain why our blob count is different.

Sent from my D5503 using Tapatalk

 

[FIZZER6]

How do you bleed the system? And what do you mean 'hot' - when the fan comes on?

The most common way to bleed the system is to leave the radiator cap loose or off and then run the bike until it gets to operating temperature, then shut off the engine. Put the radiator cap back on tight and top off the reservoir to the fill line and let it cool. Check the coolant level in the radiator after the bike cools, it should be near the top and the reservoir should still be near full.

I have found if you rev the engine a few times while bleeding it helps free up any bubbles as the water pump spins up faster can dislodge bubbles, just be careful coolant may spill.

I mean "hot" is in operating temp while idling, 3-4 bars on the temp gauge on the 2006.

 

[iSteve]

It scared me a little because what I did was a short 7km ride in the city, no hard pushing, ordinary ride and this happened.

City driving is going to cause the bike to get hot, because it has very little air flow through the radiator. Also not moving is even worst. So what happen in this situation... the fan comes on.

All perfectly normal everything is working like it should.

 

[Marcin]

So, what I did just minutes before:

1. Opened the radiator cap, saw fluid to the top under it then put it back, not tightened, only left it loose (half of the turn only which holds the cap in place but not tightens it)
2. Run the engine until two bars appeared (2 meaning 2 above the bar with the temp sign )
3. While the engine running squeezed a couple of times the big hose going from the radiator on the cap side. Some fluid came out of the cap while squeezing and at the same time coolant level from the tank under the seat lovered accordingly.
4. Turned the engine off - filled the tank
5. Repeated the squeezing and tank filling thing.
6. Tightened the cap fully.
7. Run the engine until it got hot - when 4 bars appeared (not 5, sorry ) the fan turned on. At the same time was squeezing the big hoses - the hotter the engine got the hoses became stiffer. When the fan was running I could squeeze the hoses but only slightly.
8. Turned the engine off and came to write this

What do you think of it? I believe everything is OK and I was just over reacting.

 

[FIZZER6]

That sounds completely normal to me! My fan kicks on the moment my temp gauge goes to 4 bars and it turns off when it goes back to 3 bars. Probably the same on all 2006's.

 

[Marcin]

Thank you. It seems it's my mind that is overheating. I'm glad to be a member of such a nice and helpful forum

By the way I realised that it's better to do all the possible work at your bike by yourself. While waiting for the bike to cool down I inspected rear caliper (one bolt was loose) and drained about 160ml of engine oil because the indicated oil level on the 'stick' was over the top.

 

[TownsendsFJR1300]

The hoses should be stiff with the bike hot and running!

If you can squeeze them more than maybe 1cm something is wrong. I have a 2006 as well and never had the temp go over 4 bars even in 105F humid heat!

+1 on the above 100% ^^^.

The system is also self bleeding. Go for a ride, let it cool off and top off. No secrets to it...

I would be looking real hard at the radiator cap, sounds like its NOT HOLDING pressure allowing the higher temps.. The pressurized system(hard hoses) keeps the temps down..

I live in SW Florida, low 90's now, but I try to stay out of city traffic. I have yet to hear my fan run (except when the PO was learning to ride) and have NEVER see the temp gauge above 200F in the 5 years I've owned it..

 

[FinalImpact]

I get long in the tooth - sorry.
In a nutshell; as the engine heats and cools the water expands and contracts. If there is no air in the system and the cap is holding pressure it may push a small amount of water out of the cap and into the reservoir when up to running temp (this is normal). As it cools, the water contracts, the coolant system pulls a vacuum and pulls the needed water back into the block keeping it full. All of this is dependent on the following.
- Good Rad Cap
-->> Outer main seal is effective so it doesn't loose coolant at the neck to the outside
-->> Inner seals are good and it holds pressure to rated capacity
-->> Vacuum seal is good so it can both move under light vacuum and seal under pressure.
Here are the basic parts:

For a quick spot check use the tools you have with you; your hands! Use them, feel things and touch things. Learn what boiling water feels like. Us coffee heads, feel it every morning!

Short and sweet, if you keep an eye on the temp gauge and the fluid level in the reservoir, feel that top hose on the radiator and watch the coolant level. If it says its hot and it pushing water into the reservoir, it may be real hot. but if its not boiling and the pickup tube in the reservoir is bubbling out water, its likely a bad cap. Mind you, A tiny chunk of rust under any of the three sealing lands can make the whole system inoperable.

I guess what I'm trying to say is; try to paint a bigger picture that combines all of the elements; engine temp, fluid level, your hand, and engine performance. If the engine is really hot it will (mine does) ping and detonate from a take off on cheap pump gas. Make sense?
Now if someone has a laser pointer, thats like MORE info. Use it to do a sanity check with your hand and the bar graph!


Cap is rated at something like 16 psi so as pointed out, the hoses should be hard especially if its boiling over. Water boils at 212°F, but heat it to 175f and it expands taking more volume (hose should be firming up if there is no air in the system). When the engines heat soaks the water, the pressure builds (water expanded). So, 3 parts of the cap have to work but hold on.


********* i gotta go. Will finish later...

JJD952 coolant

 

[Motogiro]

City driving is going to cause the bike to get hot, because it has very little air flow through the radiator. Also not moving is even worst. So what happen in this situation... the fan comes on.

All perfectly normal everything is working like it should.

Also just putting around town keeps the water pump spinning slower. Slow moving coolant equals less heat exchange.

My SV1000 turns on the fan at 221 F. I installed a manual switch so when I'm in stop n go traffic I can get a head start on cooling. I turn on the fan and give intermittent revs so the water pump is circulating the coolant better. It works well! My temps are good even in the desert at well over 100 F. air temperature.

Some times air can get trapped and tilting your bike from side to side can help get trapped air out of the system when filling it.

This: Check that your radiator vanes are clear so you can easily see light through the radiator... http://www.600riders.com/forum/showpost.php?p=582409&postcount=7

You could have a faulty radiator cap. this is good to watch: https://www.youtube.com/watch?v=0JdDWWoX-70T

 

[TownsendsFJR1300]

Just came back in from running around on the bike.

Happened to remember this thread while sitting at a light and checked the left side radiator hose,(from the back of the engine forward).

Engine gauge was at 170 degree's F, (fully warmed up), 80 F outside.

With moderate finger pressure (and my riding, leather gel gloves on), I COULD NOT squeeze that hose more than 1/8".

Again, my bike, as long as I've owned it,(18,000 miles on the clock presently) has never seen 200F.

IMO, if you can squeeze that hose more than that while fully warmed up to temp, I'd be looking at the radiator cap...