Please help.

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KoDen
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Please help.

Post by KoDen » Mon May 30, 2016 9:50 pm

Hi. I having an issue with coolant escaping through overflow pipe. I've asked that question on other forums. Here I've got a update of it, at what stage I'm just now.
An update. Put back thermostat, refilled radiator and reservoir. Started the engine without radiator cap. Coolant level goes down after a while and I've topped it up. Then it stay on the same level.
A while after I rev the engine, and while do so, level of coolant in radiator goes down with revs up, and high with low revs.

BUT, suddenly, coolant level start going up very fast, and it become like a fountain. As coolant go out of radiator for 2-3 inches. I've switched the engine off strait away.

Does any one know what could lead to that?

Thanks

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Gazza
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Re: Please help.

Post by Gazza » Tue May 31, 2016 2:07 am

Have you changed the thermostat? Do you have a temperature gauge and if so what does it show when the coolant expands rapidly?

Looks as if the coolant gets too hot and suddenly boils. In the past I've checked the thermostat by placing a pot of water on the stove and checked the temperature at which it opens. Check with the maufacturers spec, but it ought to be around 90°C or so. If it doesn't open by the time your water boils, then that'll likely be your problem.

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KoDen
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Re: Please help.

Post by KoDen » Tue May 31, 2016 9:36 am

That looks like coolant have been pushed out of the system with high farce. I've removed thermostat and checked it in the pan with hot water, and it start to open before water got boiled. So it working fine, and the gap it has was as in the manual.

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RK6
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Re: Please help.

Post by RK6 » Tue May 31, 2016 11:39 am

If the thermostat is ok then your next port of call should be the water pump. I don't know where they're located on the YZFR6 but it should be easy(ish) to function test. If it's working properly it should be circulating the fluid through the system quickly enough to prevent it boiling.

I would also check to ensure the fan is kicking in when it should (probably around 100c).

Other things to check:

Are you using the right mix of fluid? Obviously it will boil at a lower temp if you have too much water in the mix.

Are you using enough fluid? If it's not properly full it'll be running at a lower pressure and therefore boiling at a lower temp.

Is the expansion tank filling up before it boils over? If not, you may have a blockage which is preventing it doing it's job.

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haiax0
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Re: Please help.

Post by haiax0 » Tue May 31, 2016 3:59 pm

I second the cooling fan where applicable.. My old VFR got up to temp really quickly and anything over 100 degrees and it was pidling out the overflow..

I went through the pain of your testing.. and completely missed the fan not cutting in.

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KoDen
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Re: Please help.

Post by KoDen » Tue May 31, 2016 6:35 pm

Thanks everyone for suggestions. But I think it is fixed now. My fans working fine, and kick on at right temperature as per manual. I've been suggested what it is an air block. An it looks like it was gone with this fountain. As today I filled both system and reservoir. Keep bike running stationary for a while and gave it some good revs. Temperature goes up and fans come on as it should,then temperature goes down and fans come off. Level in reservoir went up a bit, but never escaped through overflow. Later on I went for a ride, and tried to go quite hard. Temperature first time in a week didn't go up too high while riding, only in town it was up to 100C and went down a bit, while before reach 110C. When I come back, reservoir were empty, so I've topped up a bit. Will see how it goes tomorrow.
Thanks for suggestions.

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