Topping off with different coolant?

[hypophthalmus]

My reservoir tank is low. I don't know what's in there already (assuming it's the SIGMA 30%, not totally sure what that is).

Would it be okay to top it off with automotive coolant?

[hypophthalmus]

Actually, seeing as how  the manual suggests replacing the coolant every year, I might as well do that.

It sounds like any long life 50/50 orange coolant would do the trick?

Are there any crush washers I need to worry about replacing?

[hypophthalmus]

But maybe I should avoid dex-cool? That or that's already what's in there. This has gotten complicated.

[ophelia]

There are three things I look for when I buy coolant.

universal
aluminum-engine compatible, so I don't corrode my Al engine
low silicate or silicate free, so I don't beat up the water pump on a bike

Last time, I bought a jug of Peak universal long-life coolant concentrate. It was faintly light green in colour, so it takes on whatever colour the existing coolant has. Drain the old stuff at the water pump; sometimes the right bolt has an arrow pointing to it. Drain the reservoir and remember to reattach the hose. Rinse out the system if you like, and refill again with 50:50. I like to mix with distilled water to keep dissolved minerals out of the system. Burp the system of air bubbles by running your bike for five minutes with the radiator cap off, and rev it gently from time to time.

[hypophthalmus]

Does anybody know how many times you need to burp the radiator? I'd done it about 5 times now, and it's still bubbling. I can't leave it on for very long, or else the radiator will overflow.

[hypophthalmus]

I spent a very long time doing this, and I *think* it stopped bubbling air. I took a short ride and all seemed fine. I'm still worried though. I could never run it for more than a few minutes because the coolant level would get too high. I've read things (not specific to this scooter) that say you should be running it for 15 minutes, or even an hour.  I also never noticed a drop in coolant from the thermostat opening, probably because I never ran it long enough.

[ophelia]

Most of the air should be out of there after five minutes. Put the cap back on and top off the plastic overflow tank as needed over the week.