Modern Vespa

Disclaimer: I'm not a mechanic. My Vespa mechanical skills have come from this forum and a bit of YouTube. Bought a 2007 LX 150 with 734 miles. Been sitting for years and not a scratch on it. For $1,500, I figured why not? How hard can it be to get it running again? Well, I bit harder than I imagined . . . .

Before I did anything, the engine would start, purr beautifully for 5 seconds, then die. Then it wouldn't start. I would let it sit for a day, then same thing would happen.

So, I've done the following:

1. New plug
2. New air filter
3. Drained old gas
4. Cleaned the fuel jets
5. New fuel tap
6. Added new gas and Seafoam
7. Replaced fuel and vacuum lines (Haven't removed EVAP)
8. Made sure my keys were correct and synced (or whatever the word is)

After all of that, she turned over, purred beautifully, then spit and sputtered. Did this a few times, but never ran more than 20-30 seconds while sputtering. Then she wouldn't start at all.

So I removed the carb, disassembled, gave it a good bath, then gave the parts another bath in my ultrasonic cleaner I use for fishing reels. Parts came out spotless. So far so good. When I went to re-assemble, everything went back together perfectly. I even figured out what the needle jet or collar was that I found in the bottom of the ultrasonic cleaner, and got it back in correctly. So at this point I'm getting drunk with power when I notice a split in the little boot of the plunger that seats in the float bowl.

Can someone please tell me how screwed I am? And if there is any way to unscrew myself short of buying the float bowl cover kit that has the little boot? I'd buy a new carb before buying the kit.

I've included a pic of the part. (No plastic or rubber when in the carb cleaner or ultrasonic. Just a little soap and water since it wasn't really dirty). In a perfect world, it would be great just to buy the boot, or even the plunger mechanism.

Really, really appreciate any advice. Thanks so much to all the folks who post the how-to information. You have no idea how much people like me rely on it and learn from it.

Scott

Any chance you could make a Harley boot cap work?

eBay

Very good idea. Maybe I'll swing by the local Harley shop looking particularly pitiful.

Looks like part of the accelerator pump. The rubber is there to keep the dirt out, but it should still work as is and you should be able to order that part alone.

Mine is split too. Bike runs fine.

Thanks guys. I was figuring it was just to keep out dust/dirt. I'm gonna install the carb to see if the cleaning helped. Depending on that outcome, I'll worry about replacing the boot. Or not.

Looks like it is available from Vespa, p/n 871855. Not cheap though, $12 for boot only.

The boot is not the reason your bike is dying, but if you want to replace it, just about every Chinese scooter made uses a copy of the Keihin CVK carb, and they all have rubber boots. Anybody who repairs Chinese scooters, and there are plenty in NC, will have a stack of bad carburetors somewhere, and will be able to give you a boot for very little money.

Thanks guys. Very helpful. And yes, the boot isn't the current problem. Just didn't want it to be a future problem. Won't have time to put the cleaned carb on till later in the week. Hoping that did the trick. If not, I'll be back for more advice!

I just took my carb apart this weekend due to my bike running rich and found my jet needle is bent. Is there a place where a guy can pick one up?