Engine died, and got me home only with the choke out

Tam Tam · Post by **Tam Tam** » Thu Jul 18, 2013 4:30 am

So, on my first early evening off, on the way home the stella died. It would start, but then die ( choke out, it would start, but when i pushed in the choke, the engine would rev and rev, and then die smoothly, no sputtering)

Luckily, no rain tonite, and I was only 2 miles from home, so i putted home with the choke out. Once home, I pulled off the air filter, and looked in at the carb, and realized I did not know what the hell to do next. So after looking at for a while and thinking, I put it all back together. It will start, but only runs with the choke out.

I know that the choke allows for a fuel rich mixture to start the engine, but after that I am lost. And I'm mystified as to why the engine would race and rev when the choke was pushed in.

Any advice, speculation, jokes and all are most welcome....The Coolest Thing (and capitalized on purpose) about this forum is how folk will share with and advise others with their mechanical skills when it comes to scooters.

MrChet · Post by **MrChet** » Thu Jul 18, 2013 5:59 am

Fuel/Air too lean or clogged idle jet would be where I'd start.

Has the temp drastically changed recently?

jimmbomb · Post by **jimmbomb** » Thu Jul 18, 2013 2:24 pm

My 08 did that too once. A BMW rider at a stop suggested an air leak. Same symptoms as yoy described.
Removed the air box lid, the the breather element and exposed all the jets and screws that hold the screen and such..
Turns out, the 3 screws ) flat head) that hold the screen cover and adjacent were not tight.
Tightened those up and problem solved ..
Worked for me, good luck

Tam Tam · Post by **Tam Tam** » Thu Jul 18, 2013 3:51 pm

Thanks, guys - MrChet and Jimmbomb -

Jimmbomb, I will def try to tighten everything up ...for the hell of it, I started it this morning, and same symptoms, so alas it did not fix itself

and MrChet, i will see about cleaning the idle jet, if I can. Luckily, I think I can find knowledge on here and about as how to remove the whole carb itself, and hopefully get it all back together. If it goes to shop, then i will most def give you and Jimmbomb credit for the dual diagnosis. The shop always likes it when a customer can give um an idea of what is going on, versus coming in and saying, 'It's broke - fix it'

Thanks guys!

misterbrackets · Post by **misterbrackets** » Thu Jul 18, 2013 4:45 pm

More of a question than a diagnosis here -- but, is an exhaust leak a possible culprit as well?

jimmbomb · Post by **jimmbomb** » Thu Jul 18, 2013 5:43 pm

If you find that those 3 screws near the jets were loose. ..tighten them and take it for a test run before removing jets.... good luck

BuddyRaton · Post by **BuddyRaton** » Thu Jul 18, 2013 6:16 pm

Tam Tam wrote:So, on my first early evening off, on the way home the stella died. It would start, but then die ( choke out, it would start, but when i pushed in the choke, the engine would rev and rev, and then die smoothly, no sputtering)

Luckily, no rain tonite, and I was only 2 miles from home, so i putted home with the choke out. Once home, I pulled off the air filter, and looked in at the carb, and realized I did not know what the hell to do next. So after looking at for a while and thinking, I put it all back together. It will start, but only runs with the choke out.

I know that the choke allows for a fuel rich mixture to start the engine, but after that I am lost. And I'm mystified as to why the engine would race and rev when the choke was pushed in.

Any advice, speculation, jokes and all are most welcome....The Coolest Thing (and capitalized on purpose) about this forum is how folk will share with and advise others with their mechanical skills when it comes to scooters.

You're getting it...you just need to go a little further along. OK...it revs up at idle...but was managable with the choke pulled. So what happened? Yoy have an air leak somewhere. The extra air coming in makes the mixture very lean...so what did you do?...pulled the choke reducing the air coming in from the carb and getting you close enough to the proper mixture to chug home.

See..you're understanding more than you thought you were.

Nice job!

Now you need to find the leak.

Don't be afraid of the carb. There are lots of instructions on removing, rebuilding etc. If you weren't scared to pull the top off don't let the carb scare you...you're a lot smarter than it is!

misterbrackets wrote:More of a question than a diagnosis here -- but, is an exhaust leak a possible culprit as well?

A 2T motor trying to rev out of control at idle is a classic sign of an air leak causing a way lean condition. Good suggestion to start by checking the carb.

fisher1 · Post by **fisher1** » Thu Jul 18, 2013 6:35 pm

is an exhaust leak a possible culprit as well?

If it's a bad enough leak, yes.

ScootLemont · Post by **ScootLemont** » Thu Jul 18, 2013 10:14 pm

I had a similar but not the exact problem on my 2008
It would bog down mid-throttle when accelerating - but the problem went away when riding with the choke about 1/2 way out.

Cause was a clogged main jet

Got some good advice - here is that thread
topic25374.html

This video was helpful in getting to the jets to clean them
<iframe width="640" height="480" src="//www.youtube.com/embed/OyEau3pN5wk" frameborder="0" allowfullscreen></iframe>

Tam Tam · Post by **Tam Tam** » Mon Jul 29, 2013 2:50 pm

Thank you for the youtube video link, ScootLemont.

Since the 4000 miles service was overdue, I had it all done at once, and the culprit was a clogged main jet.

But the shop also repaired my horn, my front brake lever, and a few other oddities that had pooped out.

But after watching the vid, I will now be more bold in dealing with the carb.

Thanks everyone for help and advice!

jimmbomb · Post by **jimmbomb** » Tue Jul 30, 2013 5:30 pm

So...... did your owners maintenance manual call for a 4000 mike service?

Modern Buddy

Engine died, and got me home only with the choke out

Engine died, and got me home only with the choke out

Thank you both!

Thank you everyone!