Modern Vespa

What is the correct mixture of fluids for the radiator for a GTS 250?

Carlos,

When it comes time to flush & replace my Vespa's engine coolant, I will be using that pre-mixed (50-50) light blue colored Honda OEM coolant, as I do in all my vehicles -- the same stuff used in my 2006 Honda CRV car and previously owned 2005 Honda VTX1300R motorcycle.

The blue Honda OEM coolant has no silicates, which is water-pump-seal friendly. I do not want to use a coolant that has silicates in it. I don't know how the Vespa water-pump-seal would be affected, but since I tend to err on the side of MORE concern for my vehicles' mechanics/innards than less, I only use non-silicate coolants.

I used to mix my own 50-50 coolant (distilled water only) when I regularly (for years) used Prestone (or Peak, etc.) in my cars, but those were my "ignorant silicate days."

The Honda OEM coolant comes pre-mixed -- no other way to get it -- so I just go with that.

You might want to research the silicate/phosphates issue in engine coolants before you decide on what brand/formula to use. I do not know if Vespa OEM coolant is silicate-free but I thnk it is, so be careful you do not choose the wrong formula WHATEVER brand you use.

Good luck...

Thank you, I will check into this.

You're welcome.

Check out this other older (but still informative) Modern Vespa thread on the subject of engine coolant in a Vespa:

antifreeze

At the very least, you will be aware there is more to your choice than the proper (distilled) water-to-coolant ratio -- which is generally 50-50.

Happy scootering...

What's interesting is I went to a Checker Auto store and they had about ten jugs of Prestone "Extended Life" coolant (yellow jug). Nine of the ten labels stated "Silicate, phosphate, borate free". It also stated something to the effect of being good for water pump seals. The tenth jug looked like it had been on the shelf longer, had dirt on it. The bar code was slightly different, although it registered as the same product at the counter scanner. It didn't say anything, anywhere...although the ingredient list was identical.

BTW, the grey jugs of Prestone "Dex-Cool Extended Life", stated "Silicate and Phosphate free" as well.

I've got a quart of Honda "HP coolant" premixed, green color. It's label talks a lot about silicate free and kind to water pump seals.

At Autozone, they had an Autozone brand of coolant that was labeled something like "standard"...all the other kinds they had, be it Autozone, Peak, or Prestone brand were "Extended Life". Only on this one flavor did I read in the ingredient list "silicates".

Don't forget you must use San Pellegrino water, uncarbonated.

Italian water is better!

Boondocks,

Well, the more informed we all are on these apparently simple things (like engine coolant used to be so simple decades ago) the better off we and our vehicles are!

Back in the 'old days' (I started working on my vehicles in the mid-1960s) Prestone was THE standard, was used in everything and water-pump issues (whether silicates were or were not causing any problems) wasn't known by most of us shade-tree-mechanics...we were ignorant on the subject (even IF it was known to be a problem even back then by the pros). At some point I became aware of the issue and since then, only used silicate-free formulas...in my case now, I mean that Honda OEM pre-mixed blue stuff.

Thinking back, I replaced the water pump several times (due to seal leaks, and a bit TOO often as I recollect) in the car I kept the longest (had my 1973 Datsun for 32 years and used Prestone silicate formula in it most of that time), but don't know if it was coolant-related (because it had silicates) or not. Still, I would have switched over earlier to a "water pump friendly" formula sooner had I known about it. It's sort of like when they took lead out of gasoline, and we with older cars were worried about how that would affect our valve guides from then on!

Still, 'back in the day' Prestone was THE standard anti-freeze, regardless of being chock full of silicates.

Maybe the various manufacturers of engine coolant started responding to more educated vechicle owners (and the environment) -- who knows -- but if being more knowledgeable and taking more (educated) care in choosing fluids will keep my vehicles cared for better, I am all for it.

As for Vespa's requirements, just look at what Vespa recommends (European-made coolants with specific "G" ratings) and "translate" that into what's readily-available HERE in the US...which it sounds like you are doing in comparing labels and such. And like we do with engine/hub oils and using stuff made HERE like Mobil 1 or Amsoil instead of Motul or Agip oils, for example -- which are great oils but not as easy to find locally (although I use Agip oil for Vespa's engine).

Whatever we buy nowadays -- be it car fluids or even our own food -- we should do more reading and understanding of the labels so we know what's in the stuff!

Good luck...