Cooling system

[Moses2]

Hello all.

I have changed the radiator coolant,  filling the radiator, and in between low and high on the reserve reservoir. Running the bike at idle ( with a non flashing fuel gauge-thank you all) for about 10 minutes or more, the temp gauge climbed to 7 or eight bars and the cooling fans came on. The reservoir had also climbed from between low and high, to just below high. The lines to and from the radiator all have heat. I ran it for a bit longer at idle, expecting the temp gauge to drop, but it seemed to hang there. Sound normal?

 

[RossKean]

Sounds OK but you might still have some air in the radiator.  When it gets shut off, fluid from the reservoir should get sucked back into the radiator as it cools and you may have to add more to the reservoir if it drops too far.  Sometimes it takes a few heat cycles to "burp" out all of the air in the radiator and get the reservoir so it stays between min and max.  If you add too much, it should just overflow the reservoir.

Make sure that the radiator cap is tight as well as the rubber cap on the reservoir (and that the siphon hose goes to the bottom).

I may have missed it - what was the solution to the flashing gauge?

 

[Moses2]

Rosskean, that is exactly what happened. Sucked the coolant in from the reservoir and I then refilled it. Going through another heat cycle now. Removed all the tupperware,tank and was able to get at all the spiders, except 7, tucked over the left headlight, without removing the nose. Removed,reseated and greased the clips on the other 7. Removed, reseated the ECU cable. Removed the fuel pump/sending unit and took a resistance reading across the travel of the float(I had just gone through this on an ST) and read from .019 to .139 which I felt should verify the sending unit. Reassembled, had a flashing empty bar instead of the 8 flash cycle gauge. Put a couple gallons in, and worked perfectly.

 

[Steel_Gin]

I asked the same question when I put new coolant in a couple summers ago. I had to go through three or four heat cycles (let it set overnight then checked then reservoir) before it stopped pulling fluid in from the reservoir.

 

[rbentnail]

My rules of thumb:

- fill the radiator very VERY slowly.  This eliminates the need for burping an air bubble out;

- fill the overflow container to 3/4" above the high mark. 

Works every time, without fail.  A couple normal rides later and your level is right where you need it to be. 

 

[1911]

 

[mcatrophy]

Just an observation, for when it's operating normally. I only ever check mine when it's cold before a major outing. I've found that topping it up to the max mark is a waste of coolant, next cold check it's back down to about 2/3 up from the minimum mark. 

In other words, don't think you have a problem if you keep topping it up to the max mark and it keeps going down - unless, of course, it doesn't stabilise.

I'd add that I’ve almost given up checking its level, never seems to move from this, certainly between services. 

 

[RossKean]

I've found that topping it up to the max mark is a waste of coolant, next cold check it's back down to about 2/3 up from the minimum mark. 

Agreed.  When topped to the max when cold, it expands when heated and overflows onto the road (or your garage floor).  When trying to "burp" air in the radiator, I would fill to the max when hot.  Unless there is a leak, the level will eventually stabilize - usually at 2/3 or so when cold as mcatrophy said.  Any time when it is at minimum or below when cold (after a heat cycle), it is likely that there is still some air in the system.

 

[dcarver]

On a KZ1300 burping is done by disconnecting the fan switch, run to HOT, reconnect switch.