Modern Vespa

My 2015 MP3 500ie (3rd gen) currently has about 40K miles on the clock and on its second waterpump.

The bike is driven 80% motorway, with the revs sitting between 6-7K rpm.

As of yesterday, it has started to leak yet again from the waterpump weephole / drain tube. Sometimes it drips only a drop or two, sometimes it leaves a puddle, and sometimes it is bone dry particularly if the bike is driven practically on a daily basis.

The last pump I put in was a complete pump with engine casing, not just the seals, in the hopes of prolonged pumplife. Apparently not.

What is the consensus for average pump life?

FYI, the coolant is renewed every 2 years on the clock with fresh pink G12 spec coolant.

I have never replaced mine. 50,000 miles, which started piling up in 2014.

My 2016 Mp3 500ie has 24,000 miles and original water pump. My bike is for recreation instead of daily riding, but it is ridden hard and fast on mountain roads.

Could it be something todo with the road conditions the bike is riding through? Salt corrosion, large temperature swings messing with gaskets, anything that might be affecting the bike more than other regions.

2008 MP3 500 original water pump at 81,500+ miles

My Fuoco back in the day needed a new pump at ~40,000 miles in ~2010.

It had been ridden pretty fiercely, if that makes any diference. Just a datum point.

I suppose it could be environmental, although that would be strange.

My MP3 sits outside summer and winter, but in a covered space to keep it out of the sun and rain.

Could the leaking water pump be a symptom of something else deeper in the engine? Something that drives the water pump is oscillating, excessive vibrations, something wearing down the seals faster?

Is this the plastic or metal version? Water pump covers MP3 500 ie

If its seals, could the pump be retained but the stock seals replaced with something workable but more durable?

My own MP3 is also stored outdoors under a fitted cover in all weather, no environmental issues that I can find on it.

I've got the aluminum type pump.

I'm starting to think it is my driving habit that might the cause. I use it mainly for work commute, about 40 miles each day but pretty much all high speed freeway.

Always sitting between 120-130km/h so the engine is turning around 7K rpm for prolonged periods.

No signs of oil in the coolant, and no signs of coolant in the engine oil. And the coolant expansion tank does need to be topped up about every 2-3 weeks.

Maybe, but wouldn't something else break or start coming loose first? I'm not much of a mechanic, but it seems odd that the water pump breaks first and not something more critical to the engine.

What powers the water-pump? If its powered some form of direct connection to the crank shaft then perhaps that component is starting to fail and the water pump is a symptom of that.

I'm contemplating throwing a new radiator cap at it, on the off chance that the current one (the one that came from the factory) is not relieving pressure properly and causing excessive pressure buildup and thus potentially the strange leak behavior (sometimes one or 2 drops, sometimes a puddle, sometimes nothing).

If everything is working properly except the radiator cap is not venting, there should still be no need for the cap to vent. It vents when something is wrong, and allowing the coolant to get too hot. Blocked radiator fins (full of dirt and bugs, for instance) could be the culprit. If it's overheating, that is.

Radiator fins are perfectly clean and straight. Not a single bug or spec of dirt/mud. Temp gauge stays perfectly straight up and (depending on ambient temp) even just a hair under. Aux fan triggers on as soon as the gauge passes the midway mark, and goes off as soon as the needle is back at the midway point.

I've already ordered a new cap today along with a Piaggio maintenance kit since it is due soon for a belt & air filter service and front brake pads are not far behind.

The MP3 was put into its yearly storage last weekend until the late fall/early winter comes around.

When I get it back, I'll do a coolant service as well and stick a endoscope into the passages around the water pump to make sure there is no buildup of any type.

It's a strange event. Never encountered anything like it on other vehicles during the last 50 years.