Coolant system problem

[andrewsmith]

How do all

Another thing has gone wrong with me curvy

Whats happened is the bike started running hot last nite on the run home, checked it this morning to find that its used 500ml of coolant in 1200 miles.

Today ran it through to the gym and the fan kicked in (6 miles with the last 2 in stop start traffic) and a little pond of coolant appeared just afterwards.
I'm not to concerned about the pond as I'm guessing its just the overfill coming through the system.

Any suggestions to what the cause/ culiprit is.
Really wanting to know for how much more me service on Tuesday is going to cost.

1st of all make sure the main system is full and the overflow bottle.
Then making sure you can see all the hoses and where they connect run the bike and let it get hot.
Could just be a loose connection unless theres lots of almost chalky dirt around the front of the bike then your rad may be leaking.

[flymo]

probably an obvious question but where is it leaking from?

[andrewsmith]

where the dump of coolant was from the rubber pipe on the r/h side next to the crank cover.

Bbadger, its definately not a goosed radiator nothing building up around the rads

[flymo]

If its pumping coolant out of the overflow then its likely the system is overheating, unless of course there is too much coolant in the system in the first place.

Check the coolant level on the expansion bottle and make sure its within limits, not just full to the brim. If its particularly low and still pumping coolant out then there may be some further investigation required.

[yorkie_chris]

Sounds like it's been overfilled.

[embee]

Could be the rad cap gone faulty, if it isn't maintaining system pressure you'll end up losing coolant. Check the condition of the rad cap seals and springs.

Thermostats are designed to fail open so that's unlikely to be the problem, though it's worth checking it if your problem persists.

Not specific to the SV but for engines generally, it's not unheard of for coolant pump impellers to lose blades or blades to be eroded away, or the impeller come loose on the shaft etc. These problems all end up with reduced coolant flow rates so temperature differences increase (coolant out of engine ends up being hotter).

[andrewsmith]

there definitely was an overfill (didn't pay attention when filling).

But what a got me its burned through about 500ml in 1000 miles.
To give an update, had the fairing off and looked at:
- rad cap, no issues
- Rad fine except for small damage to fins off a stone
- hoses all fine and no signs of a blockage
- Coolant was absolutely minging and i would guess i ain't ever been changed

I did a warm up on the bike and let is get hot, pump seems fine as the radiator got hot and the fan kicked in after a good 10 minutes of idling.

Embee the pump issue has happened to me old man before with a car the remains of the pump were impressive

Check and clean your rad cap very carefully. I've had the tiniest bit of crud (seriously tiny) wedge in the valve in the cap which has caused the coolant to boil in the expansion bottle and overflow. I had it twice on my Daytona and a mate had it on his R1 whilst on holiday.

Edit: The coolant didn't actually boil in the expansion vessel but the loss of pressure from the cooling circuit caused it to boil on it's way there.

To put it simply whilst ANY vapour, be it H2O or CO2 is under pressure (gas, liquid, vapour- remember GCSE physics?), it's boiling point rises the more pressure it's under, and likewise the less pressure it's under it will boil at a lower temperature.

If you try boiling a kettle at several thousand feet it will boil at less than 100 degrees. If you tried boiling water at thousands of feet below the Earth's surface it would boil at over 100 degrees.

The radiator cap on any vehicle keeps it pressurised up until a certain point which is when it will let water through into the expansion vessel. If you're loosing coolant via the expansion vessel due to the water let through boiling then it's being allowed to pass through under much less pressure or because the valve is being held open hense the suggestion of crap in the valve or it being faulty.

This might help you get your head round it:
http://www.familycar.com/classroom/coolingsystem.htm

[Sid Squid]

Originally Posted by embee

Could be the rad cap gone faulty.

+1 The first thing I'd check.

Originally Posted by andrewsmith

- rad cap, no issues.

Are you certain? This does not mean a leak from the area of the cap - it means the cap allowing coolant to pass into the expansion tank and the system not pressurising thus lowering its boiling point.
Many don't realise it but the cap is not just a lid, it is two valves, one heavier one to cause the system to pressurise, one light one in the opposite direction to allow coolant to pass back into the system under atmospheric pressure as the system cools. A common problem is simply dirt under the rubber - the cap doesn't seal correctly.