Modern Vespa

Hi Everyone,

I know a coolant leak is covered in some of the older threads, and I did read some of them, but I am new to modern (been riding vintage for years though) and really just want to start a fresh thread and also introduce myself. I learned so much about my vintage scooters from the old Scooter BBS, and hope to do the same here.

I decided to buy a modern Vespa after I went to a non-vintage rally and saw how much fun everyone was having. I mean, I also had fun, but not the carefree kind they seemed to be having. They would start up and go while I was kicking the crap out of my vintage scoot just to get it started (have since cleaned the carb, so it's fine now). So I put the word out that I was looking and someone sold me a 2009 GT200 that was cheap and in amazing condition with low miles with the intention of riding out to that same rally. I got hit in an intersection a week later and messed up my leg so riding was out for awhile. Actually, as I was hitting headfirst into the windshield, I was thinking I would never ride again.

I was so mad that I had only started to experience the joy of an automatic, that I put the word out again to try and buy another one. I found a good deal on a 2007 GTS250. After trailering it home I took it around the block and parked it for the winter. Of course, like everyone does with a new to them scooter, I had to go gawk and admire it the next day. Well there was a puddle under it. It was coolant. I put cardboard under to see if I could detect the drip. That didn't really help too much. I took off some of the plastic and tightened every clamp I could, and did the same around the engine compartment. It is still leaking. I have not been able to find the origin. Maybe because everything is so dirty.

My questions are about where to start. I think the engine is pretty dirty, so I may want to clean it up first to really see what is going on. So I plan to do that, and go from there. I will take any tips. I checked the oil and it looks good. There is one hose that does not have a clamp, and I want to figure out what that is doing. I have downloaded the shop manual so am reading that over as well to get oriented.

Thanks in advance, and come to BANDCAMP
Anne from PVSC

the hose that has no clamp is your fuel hose. don't worry about it, it's supposed to be that way.

the usual coolant leak culprit is the hose clamp on the thermostat housing. so check/replace that first.

coolant coming from the t-stat housing area (so, t-stat housing itself, bypass, of or the hose) usually drips down the back of the cylinder, along down the side and then wicks along the bottom of the cylinder and drips down. so clean all of that really well and then inspect for leaks.

if it's none of that, then it could be a base gasket or head gasket. or possibly another hose is leaking.

get some pics of the t-stat and hose first as well as underneath by the exhaust port/header and barrel/head. maybe something will clue us in.

I might be chasing shadows...

I zoomed in on the last photo, and looking at the thermostat cover and bleeder, it looks like some dried stains/trails of leaking. Is that screw/bolt near at the lower arrow wet?

That bleeder screw (under that tiny rubber boot) is often tightened too far and it strips in the cover. It's used to bleed the air from the coolant system. Much beyond finger tight, and it strips out. I can't imagine a 2007 GTS has not had at least a few coolant changes. Cleaning up the engine bay might help, but you might easier find the leaks when its running and the coolant system gets pressurized.

And oh, welcome to MV (I sorta miss the old BBS too)

Thanks, I'll check there this weekend.

Thanks for the welcome! I will check that area this weekend.

Not to question your expertise on deciding if it's coolant or not, but just to be sure: have you tasted it? In other words: are you 100% sure it's coolant?

(Asking because I myself thought I had a coolant leak, but it wasn't coolant, it was just condensation dripping from the engine in my currently way too moisty shed.)