GSX-R 1000 K5 Coolant is boiling and overflowing
Discussion
Hi Guys,
In the winter I had my radiator repaired as the fan rubbing against it caused damage to it. The bike was fine for 1.5 thousand miles after which the coolant would boil and then overflow out of the expansion bottle after switching bike off (coolant tempreature would be about 100 degrees)
Anyway, mechanic drained and filled with distilled water and previous coolant (thus, not a full 50:50 mix) and I have been running the bike for the last week (~300 miles covered) only for the boiling noise to 'mildly' start to appear again (but no discharge so far).
Here is a summary of what has been done to the bike since the problem began:
- Thermostat replaced
- Radiator cap replaced
- All hoses checked for leaks and none found
- mechanic checked that there is no oil in water
- radiator drained and then refilled, bled via screw under petrol tank as per service book
Note 1: Bike used to run at 74 degrees when riding, but now runs 64 degrees (this could be due to the fact that their is more water than coolant in mix). But its strange that its operating temperature is 10 degrees lower than before
Note 2: Mechanic doesnt no what else could be causing boiling coolant and after he bled it, it disappears. Thus, air is gradually being re-introduced as I do successive rides.
> My plan is to put the correct 50:50 mix of coolant/distilled water this week.
> But I also want to rule out headgasket damage, before I start replacing water pump or other coolant components
>Is there a kit available to detect exhaust gases in radiator fluid? I don't have a smoking exhaust, nor any loss in performance.
I am VERY frustrated with this issue at the moment. I am even thinking that I may have to live with it, and just wire the fan so I can manually overide it.
Any opinions on what steps I can take to solve the problem are greatly appreciated.
In the winter I had my radiator repaired as the fan rubbing against it caused damage to it. The bike was fine for 1.5 thousand miles after which the coolant would boil and then overflow out of the expansion bottle after switching bike off (coolant tempreature would be about 100 degrees)
Anyway, mechanic drained and filled with distilled water and previous coolant (thus, not a full 50:50 mix) and I have been running the bike for the last week (~300 miles covered) only for the boiling noise to 'mildly' start to appear again (but no discharge so far).
Here is a summary of what has been done to the bike since the problem began:
- Thermostat replaced
- Radiator cap replaced
- All hoses checked for leaks and none found
- mechanic checked that there is no oil in water
- radiator drained and then refilled, bled via screw under petrol tank as per service book
Note 1: Bike used to run at 74 degrees when riding, but now runs 64 degrees (this could be due to the fact that their is more water than coolant in mix). But its strange that its operating temperature is 10 degrees lower than before
Note 2: Mechanic doesnt no what else could be causing boiling coolant and after he bled it, it disappears. Thus, air is gradually being re-introduced as I do successive rides.
> My plan is to put the correct 50:50 mix of coolant/distilled water this week.
> But I also want to rule out headgasket damage, before I start replacing water pump or other coolant components
>Is there a kit available to detect exhaust gases in radiator fluid? I don't have a smoking exhaust, nor any loss in performance.
I am VERY frustrated with this issue at the moment. I am even thinking that I may have to live with it, and just wire the fan so I can manually overide it.
Any opinions on what steps I can take to solve the problem are greatly appreciated.
Yes no problems before radiator change, and then no problems for 1.5k afterwards. The repair seems ok, because their is no leaking from where it was repaired. However, it could be a possibility as it is the only changed factor in all of this.
To be honest my mechanic kept the old thermostat so i cant really compare it to new one.
edited to add: I took the bike to the mechanic on two seperate occasions, and both times he bled it. Their was no boiling/overflowing for about 200 miles, and then it would slowly come back. This indicates that it is bled correctly, but air is coming in from somewhere over a few heat cycles.
To be honest my mechanic kept the old thermostat so i cant really compare it to new one.
edited to add: I took the bike to the mechanic on two seperate occasions, and both times he bled it. Their was no boiling/overflowing for about 200 miles, and then it would slowly come back. This indicates that it is bled correctly, but air is coming in from somewhere over a few heat cycles.
Edited by JimClark49 on Sunday 13th April 13:33
Thanks for the many excellent replies guys.
With regards to the headgasket - the oil looks normal (brown colour, not milky), the mechanic said their was no oil in the water of radiator, and there is no smoke from the exhaust (except some initial condensation on startup).
Also, I have done 7.5k miles on the bike, and not once have I done anything which would cause a headgasket failure i.e. I have never let it overheat, and it is always warmed up before riding hard. I always thought headgaskets failed if you let the engine overheat.
The thermostat is new, so I cant see how it could give a faulty reading. I think the low reading is either due to an efficient radiator (as it was flushed when repaired), or air in the system messing up the temp reading.
The fan is wired correctly and kicks in when it should. It is sucking air towards engine and does cool the bike down correctly.
I hope to ride it more in the next few days and will see if the problem gets worse.
With regards to the headgasket - the oil looks normal (brown colour, not milky), the mechanic said their was no oil in the water of radiator, and there is no smoke from the exhaust (except some initial condensation on startup).
Also, I have done 7.5k miles on the bike, and not once have I done anything which would cause a headgasket failure i.e. I have never let it overheat, and it is always warmed up before riding hard. I always thought headgaskets failed if you let the engine overheat.
The thermostat is new, so I cant see how it could give a faulty reading. I think the low reading is either due to an efficient radiator (as it was flushed when repaired), or air in the system messing up the temp reading.
The fan is wired correctly and kicks in when it should. It is sucking air towards engine and does cool the bike down correctly.
I hope to ride it more in the next few days and will see if the problem gets worse.
Ok, so I did alot of miles with the bike today, and the problem is still there. So basically once it is bled it is fine, but after a few rides air is getting into the system again and causing the coolant to boil.
I took it to my mechanic late afternoon and we discussed some more about it.
He told me that it wont be the radiator as radiator fins wont suck air in to a pressurized system. Also, if the area where it was repaired had a hole, then water would leak from that hole, yet there is no leak anywhere on the radiator.
One suggestion was the water pump. If it creates air bubbles in the coolant, then the gradual build up of these could cause air to be in the fluid.
He is going to speak to some colleagues who work on race bikes etc. to see if they have come across this problem and what a solution can be.
In the meantime he has suggested that I top up with distilled water everytime.
I took it to my mechanic late afternoon and we discussed some more about it.
He told me that it wont be the radiator as radiator fins wont suck air in to a pressurized system. Also, if the area where it was repaired had a hole, then water would leak from that hole, yet there is no leak anywhere on the radiator.
One suggestion was the water pump. If it creates air bubbles in the coolant, then the gradual build up of these could cause air to be in the fluid.
He is going to speak to some colleagues who work on race bikes etc. to see if they have come across this problem and what a solution can be.
In the meantime he has suggested that I top up with distilled water everytime.
moto_traxport said:
Sounds like poor circulation / partial blockage in system somewhere to me. (Edit either air or some of the "repair" is got stuck somewhere?).
Might explain lower initial rad temperature, eventual boiling and cavitation by the water pump. I would first try a 1.2 bar rad cap rather than the normal 1.1 bar job - bit more pressure might solve it, otherwise I'd pull the cooling system to bits as best I could.
Thanks for the suggestion mate. Where could I get a 1.2 bar rad cap that fits my bike? Might explain lower initial rad temperature, eventual boiling and cavitation by the water pump. I would first try a 1.2 bar rad cap rather than the normal 1.1 bar job - bit more pressure might solve it, otherwise I'd pull the cooling system to bits as best I could.
Quick update...
Yesterday evening my friend (competent home mechanic) and me did some further testing. We disconnected different hoses and sealed a garden hose to pass water through the cooling system (including radiator) and there was very good flow and no sign of any blockages.
We then opened up the water pump to inspect it, and it looked good. There was no broken blades and it turned freely when we turned the back wheel (while in gear).
Thus, it seems the headgasket is the only logical explanation. We have a mechanic friend who will do a block test in the coolant tomorrow to detect evidence of any exhaust gases in coolant. Hopefully, I will have more of an idea on what is the cause after this and can plan on getting it sorted.
PS: if it is a headgasket, is there anything I can do to increase performance while the head is off?
Yesterday evening my friend (competent home mechanic) and me did some further testing. We disconnected different hoses and sealed a garden hose to pass water through the cooling system (including radiator) and there was very good flow and no sign of any blockages.
We then opened up the water pump to inspect it, and it looked good. There was no broken blades and it turned freely when we turned the back wheel (while in gear).
Thus, it seems the headgasket is the only logical explanation. We have a mechanic friend who will do a block test in the coolant tomorrow to detect evidence of any exhaust gases in coolant. Hopefully, I will have more of an idea on what is the cause after this and can plan on getting it sorted.
PS: if it is a headgasket, is there anything I can do to increase performance while the head is off?
Hi all,
Had block test done today and it came back negative (i.e no colour change). So head gasket is likely to be good.
My friends mechanic swapped the radiator cap to a TLR 1000's (which is the same pressure rating as the GSXR -1.1 bar) and the discharge stopped and the cooling system was behaving properly. When they put my cap back on it continued to behave itself.
Some theories:
1) When the radiator was refurbed maybe the area where the radiator cap goes was distorted (perhaps it was dropped in the workshop?). This might not allow the cap to seal properly causing my problems.
2) A different rad cap (the TL had a thicker seal), may have pressurized the system correctly and dislodged a blockage. This in turn could be making the cooling system perform correctly (I am sincerely hoping that this was the cause).
The next step is to let everything cool and then heat the bike up again tomorrow to see if it behaves itself.
At the moment everything is pointing to a defect in the radiator, rather than the engine - which is a massive relief for me.
Had block test done today and it came back negative (i.e no colour change). So head gasket is likely to be good.
My friends mechanic swapped the radiator cap to a TLR 1000's (which is the same pressure rating as the GSXR -1.1 bar) and the discharge stopped and the cooling system was behaving properly. When they put my cap back on it continued to behave itself.
Some theories:
1) When the radiator was refurbed maybe the area where the radiator cap goes was distorted (perhaps it was dropped in the workshop?). This might not allow the cap to seal properly causing my problems.
2) A different rad cap (the TL had a thicker seal), may have pressurized the system correctly and dislodged a blockage. This in turn could be making the cooling system perform correctly (I am sincerely hoping that this was the cause).
The next step is to let everything cool and then heat the bike up again tomorrow to see if it behaves itself.
At the moment everything is pointing to a defect in the radiator, rather than the engine - which is a massive relief for me.
VidalBaboon said:
Have you checked the operation of the thermostat? Pull it out and pop it in a container of boiling water. If it doesn't open fully, you have found your culpret.
It's not uncommon for thermastats to be unservicable on fit, and i'm pretty sure I used to check them before putting them into a customer's car when i was an apprentice, but I've drunk too much beer since and can't fully remember...
My mechanic fitted a brand new thermostat a few weeks ago. That was the first thing we changed. Are you saying that we should check even a new thermostat before fitting?It's not uncommon for thermastats to be unservicable on fit, and i'm pretty sure I used to check them before putting them into a customer's car when i was an apprentice, but I've drunk too much beer since and can't fully remember...
OK i see the point with the thermostat, but I think its working correctly.
From my understanding a thermostat controls when the coolant goes into the radiator to be cooled. Given that the whole radiator is nice and hot at operating temperature - this would suggest that the thermostat is opening and letting water pass into the radiator.
From my understanding a thermostat controls when the coolant goes into the radiator to be cooled. Given that the whole radiator is nice and hot at operating temperature - this would suggest that the thermostat is opening and letting water pass into the radiator.
Hi All,
Thanks for the recent replies and sorry for not replying to them sooner.
I have tested the bike yesterday and to my sadness the problem has returned again!
The blades of the water pump were plastic I think.
I am going to call Aprillia Performance in Tamworth tomorrow and get them to look at it.
Thanks for the recent replies and sorry for not replying to them sooner.
I have tested the bike yesterday and to my sadness the problem has returned again!
The blades of the water pump were plastic I think.
I am going to call Aprillia Performance in Tamworth tomorrow and get them to look at it.
Thanks Mike150. My bike doesn't seem to be boiling under load, it boils at idle. When I get moving and the temperature cools, the boiling disappears, even if ridden hard.
Today I spoke to Aprillia Performance on the phone. I explained to them the story and the guy kindly spent more than 20 minutes explaining what it could possible be.
Here's his theory:
1) The bike has a pressure leak somewhere (possibly the radiator) which is causing the water to boil much earlier than it should.
>rationale: A 1.1 bar radiator cap means that the system can hold 1.1 atmospheric pressure and this equates to about 110oC boiling point. However, since my coolant starts boiling around 93oC it means the system is not holding enough pressure and the fluid boils much earlier than it should.
>>Test: He told me to see if the filler neck of the radiator has any dents or to listen for hissing noises from this area while bike is running (preferably using a stethoscope).
>>>Solution: new radiator
2) The thermoswitch (which I presume is attached to the radiator/fan) might be faulty and this could be causing the low running temperatures. Alternatively, low running temp could be due to an efficient radiator (as it was flushed during repair). Though I think it is unlikely to be this, as otherwise I would have noticed this in the first 1.5k since radiator repair.
I will check the radiator filler neck for hissing/leaks, but dont really know where to start with the thermoswitch. I am thinking of just buying a new switch and trying that, as at least it rules it out if problem still occurs.
Anyway, will keep you updated about this strange and stressful saga!
Today I spoke to Aprillia Performance on the phone. I explained to them the story and the guy kindly spent more than 20 minutes explaining what it could possible be.
Here's his theory:
1) The bike has a pressure leak somewhere (possibly the radiator) which is causing the water to boil much earlier than it should.
>rationale: A 1.1 bar radiator cap means that the system can hold 1.1 atmospheric pressure and this equates to about 110oC boiling point. However, since my coolant starts boiling around 93oC it means the system is not holding enough pressure and the fluid boils much earlier than it should.
>>Test: He told me to see if the filler neck of the radiator has any dents or to listen for hissing noises from this area while bike is running (preferably using a stethoscope).
>>>Solution: new radiator
2) The thermoswitch (which I presume is attached to the radiator/fan) might be faulty and this could be causing the low running temperatures. Alternatively, low running temp could be due to an efficient radiator (as it was flushed during repair). Though I think it is unlikely to be this, as otherwise I would have noticed this in the first 1.5k since radiator repair.
I will check the radiator filler neck for hissing/leaks, but dont really know where to start with the thermoswitch. I am thinking of just buying a new switch and trying that, as at least it rules it out if problem still occurs.
Anyway, will keep you updated about this strange and stressful saga!
Ok just been working on bike this morning. I have bled the bike and the boiling has stopped, but I know that after a few days riding it will return.
Can loss in pressure from cooling systems be gradual, i.e. over a a few successive heat cycles?
I used my mechanical stethoscope to listen for noises near filler neck/radiator cap and although there was clear noise that could be heard, didnt seem to be different from what I could hear in other parts of the radiator.
I am going to see if someone on the GSXR forum has a spare radiator which i could try and see if it makes a difference.
Can loss in pressure from cooling systems be gradual, i.e. over a a few successive heat cycles?
I used my mechanical stethoscope to listen for noises near filler neck/radiator cap and although there was clear noise that could be heard, didnt seem to be different from what I could hear in other parts of the radiator.
I am going to see if someone on the GSXR forum has a spare radiator which i could try and see if it makes a difference.
Thanks for the suggestions eldons and biffonracing.
The bike is using no coolant. The resorvoir bottle stays at the correct level until it boils over after about 300 miles of riding.
I have had a car block test done and it came back negative. The mechanic did say that some water got into the tester thingy and might have affected the findings.
It could be the headgasket, but at the moment there are no other signs suggesting this. If all else fails I will have to get a compression check done on the cylinders.
I did remove the engine coolant sensor today and it was covered in a film of limescale. I cleaned it up, applied some ACF50 to it and re-inserted. I might just change it for a new one to rule it out completely.
My thoughts keep making me think that the filler neck of the radiator is warped and is gradually allowing pressure to escape, which means after a few days the system is boiling over. When I bleed the system, the pressure is built back up again, the bike is fine and then the cycle starts again.
The bike is using no coolant. The resorvoir bottle stays at the correct level until it boils over after about 300 miles of riding.
I have had a car block test done and it came back negative. The mechanic did say that some water got into the tester thingy and might have affected the findings.
It could be the headgasket, but at the moment there are no other signs suggesting this. If all else fails I will have to get a compression check done on the cylinders.
I did remove the engine coolant sensor today and it was covered in a film of limescale. I cleaned it up, applied some ACF50 to it and re-inserted. I might just change it for a new one to rule it out completely.
My thoughts keep making me think that the filler neck of the radiator is warped and is gradually allowing pressure to escape, which means after a few days the system is boiling over. When I bleed the system, the pressure is built back up again, the bike is fine and then the cycle starts again.
Quick update guys...
Today I decided to remove the radiator and take it to get pressure tested.
First pic shows the repair which developed a crack and would have been leaking tiny amounts of water/coolant.
Second pic shows the repair done by the radiator guys today. When they pressure tested it, they said it was losing only tiny amount of pressure over the hour, which possibly corresponds with why the problem used to occur gradually after 300 miles
I will add coolant tomorrow and then test the bike over the week. Hopefully this will be the end of the issue.
One question: Where do you guys get your coolant from? Will Halfords concentrated antifreeze/coolant be OK?
Today I decided to remove the radiator and take it to get pressure tested.
First pic shows the repair which developed a crack and would have been leaking tiny amounts of water/coolant.
Second pic shows the repair done by the radiator guys today. When they pressure tested it, they said it was losing only tiny amount of pressure over the hour, which possibly corresponds with why the problem used to occur gradually after 300 miles
I will add coolant tomorrow and then test the bike over the week. Hopefully this will be the end of the issue.
One question: Where do you guys get your coolant from? Will Halfords concentrated antifreeze/coolant be OK?
theshrew said:
I have to be honest ive never seen a rad repair like that before, normally I just see people replace the core.
Anyway hope it works and your get riding again. As for the anti freeze check the spec and how much you need in your handbook. Halfrauds or a local place will have what you need.
Thanks mate. Yes the plan was to have it re-cored, but the guy then said he could repair it and guarantee that repair for 12 months. Lets hope this new one holds.Anyway hope it works and your get riding again. As for the anti freeze check the spec and how much you need in your handbook. Halfrauds or a local place will have what you need.
I bought 2 liters of Fuchs Pro Coolant ready mixed (50:50). My bike takes 2.4L of coolant, so I just added 0.4L of distilled water. This will slightly affect the 50:50 ratio of coolant to water, but do you guys reckon I will be OK to run it like this through the cold winter temperatures?
Momentofmadness said:
How are things with the K5? Hope you got it sorted 
Hi mate,Sorry for the late reply, I havent logged in and checked on here for a few weeks.
But the update is that the problem is sorted.
The crack in the radiator repair was the culprit. Even the re-weld they did under warranty failed after two days riding (circa 300 miles). So I bit the bullet and bought a brand new radiator for 582.14. Having ridden the bike for last couple of weeks, everything has been fine.
So in summary, the root cause of problem was a radiator leak, which lead to a loss in pressure, which in turn lowered the boiling point of the coolant and hence my problems.
Hopefully, this thread will help someone else in a similar predicament in the future.
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