Modern Vespa

I have a 2008 MP3 500 that I want to change the antifreeze. A dealer told me best way to drain was to remove water pump cover. Is there any thing special I need to do when I refill. How do I get air out of the lines? Thanks in advance for your input.

The water pump cover is exposed and relatively easy to get to, so that probably influences his suggestion. Should probably plan for a new gasket or o-ring if you go that route. Also plan a bucket and rags because the coolant will be going everywhere.

There is a bleeder screw near the top of the engine to let the air out. Once you refill you need to run the engine up to temperature so the thermostat opens and the coolant is flowing, then open the bleeder until no more bubbles.

Also a good time to inspect your hose clamps and decide if you would like to replace them.

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Use the metal gasket that Piaggio sells. A paper gasket is not going to hold up the long haul.

One more thing: the plastic version, even with new and fresh "o-ring", could leak without sealant. Plastic pump was replaced by metal one in new versions, and that metal one is a replacement for plastic one's by parts catalogue.

I found that during my Big Beo's engine overhaul and had to flush the coolant another time. Said bad words. Lots.

Do you mean the pump housing is now metal or the impeller? When I looked up parts I saw the oring but did not see any other gasket. Guess I missed it, will have to take another look. Thanks for info. Guess I should go ahead and replace with the metal while I have it off.

The O ring was ditched with a updated design of the cover that uses a metal gasket.

AFAIK, all the current 500 engines (2014 onwards???) use the updated cover and gasket. In the US, that would be 2016 and newer.

I replaced mine because the plastic housing was cracked and repaired badly before I acquired it.

Expected that the gasket came with the new housing. It didn't.

Hand cut thick fiber gasket is still holding a year later.

The housing. There were three of those housings for 400/500cс, and only one is recommended to be used. It is B019381, should be used only with gasket 879210