Modern Vespa

Very good chance it's a loose hose clamp on a coolant hose

Looks more like coolant to me.

But, why no clamp on your exhaust?

My 2009 GTS developed a leak like that at 20,000 miles. I replaced the head and base gasket and it went away. Mine only happened after a ride. I would clean it up after it cooled and no leak. Next ride it was back.

So you ruled out a loose clamp or leak from somewhere other than the head?

You can get a complete top end gasket kit, with everything you need to do the top end for $60. We have them. The part number is 4975516.
Take photos before you take everything apart, so you know how it goes back together. Disconnect the battery before you start taking the engine out.

Keep up the good work. Positive vibes directed your way!

I can't believe but I actually detached the engine! I don't know if I will be able to put back together,

Good work. Be careful you don't have any screws left over.

This winter I did a head gasket and Base Gasket putting a Malossi kit on my GTV 300.

A tip I learned and will always use when doing major motor work. I went to Goodwill, purchased Cup Cake trays. 2 of them about 10, 12 Cupcake slots per tray.
I used 1 tray for the Left side of the bike and a tray for the right side of the bike.

Made organizing and reinstallation very simple. When the trays are empty, then you are done.

I have multiple GTS 300's which I adore, however I always go back to the GTV, why? Because I rebuilt it. Once you are done, you will be giving yourself a High five, everytime you ride it.

Did you do a bigger displacement cylinder and the Maolssi head? Did you get good gains?


Good luck.

I also just rebuilt a top end with new cylinder/piston/head/waterproof. In fact, I did it twice because one of the engine bolts twisted and broke when torquing down the engine. I had to order 4 new bolts and take it apart and do it again!

I ran into other issues... like the exhaust rocker had a flat spot and the camshaft was galled slightly there. I ordered an original equipment replacement rocker from a shop in Italy, and it took 6 weeks in the Italian Post before it got here, so a weekend job turned into two months.

When the time came, it cranked first time, ran for 20 minutes to do a muffler paint bake , then ran 130 miles two weekends ago. All seems okay so far! No coolant or oil leaks inside or out. I'm cautiously optimistic that my rebuild is good.

This is a 2016 GTS purchased very cheaply with the description "blown head gasket". I decided to do a top end rebuild with an inexpensive known good head, new cylinder and piston, and a waterpump for good measure.

where did you buy those spare parts?

If that bushing looks like that, I wonder what the Shock bushings look like? Should they be replaced as well?

They should be fine pretty much for the life of the bike.

If those crankcase silent blocks are compromised, then it's worth checking the swing-arm needle bearings while the engine is out. That's the swingarm in front of the engine, NOT the exhaust support bracket that everyone mistakenly refers to as the swingarm.

I also just rebuilt a top end with new cylinder/piston/head/waterproof. In fact, I did it twice because one of the engine bolts twisted and broke when torquing down the engine. I had to order 4 new bolts and take it apart and do it again!

As I wrote earlier:




So, been there done that. You should get 4 new cylinder head studs and try again. Things like base gasket and head gasket are single torque items, so you should also replace those again too, even though they are brand new.

I also just rebuilt a top end with new cylinder/piston/head/waterproof. In fact, I did it twice because one of the engine bolts twisted and broke when torquing down the engine. I had to order 4 new bolts and take it apart and do it again!

I ran into other issues... like the exhaust rocker had a flat spot and the camshaft was galled slightly there. I ordered an original equipment replacement rocker from a shop in Italy, and it took 6 weeks in the Italian Post before it got here, so a weekend job turned into two months.

When the time came, it cranked first time, ran for 20 minutes to do a muffler paint bake , then ran 130 miles two weekends ago. All seems okay so far! No coolant or oil leaks inside or out. I'm cautiously optimistic that my rebuild is good.

1. you are amazing
2. this is inspiring. I was on the edge of giving up today, but now i feel re-energized.
This is a 2016 GTS purchased very cheaply with the description "blown head gasket". I decided to do a top end rebuild with an inexpensive known good head, new cylinder and piston, and a waterpump for good measure.

thanks for the tip! tell me how do you screw the stud and unscrew it? with pliers or is there a special tool?

thanks for the tip! tell me how do you screw the stud and unscrew it? with pliers or is there a special tool?