Ninja 250 2010 where to start?

[adidasguy]

Helping a friend. So a few pointers to start with would be appreciated. We think stuck floats so here's the story:

Friend bought it and it was ridden to his house. After that, it would never run.
It tries to start but goes nowhere.
The little drip hole at the bottom of the exhaust (we have that, too) to let water drain from the exhaust drips gas. So lots of gas is just going right through the engine into the exhaust.

Battery good and re-charged. Was told this bike doesn't like the choke.

Service manual will be here in a couple days. Owners manual in hand so at least for now I can turn off the gas completely.

We figure a day will get it running again. Most likely stuck floats. Bike has 1000 miles on it.

I'm posting here for suggestions as you guys & gals know my level of experience. That will make it easier to tell me where to go and what to check without having to explain what a screw driver is.

I will post pictures. This is the first major non-GS500 project for the bike cave.

[crzydood17]

BURN THE NINJA! 

[Big Rich]

I've never worked on a Ninja, so keep that in mind.

Could be as simple as the valves needing adjusted. Or the idle / pilot jet being clogged, and it's pumping too much gas into a cold cylinder to fire.

[adidasguy]

He came by with more info after delivering the bike to the Bike Cave.

Ran fine.
Sat for 3 months
Sort of fired up but any throttle would kill it.
Now, 6 weeks later, won't fire up and gas dripping
Did get fresh gas and oil change
That's all that has been done so far.
Friend is a noob at bikes so I'm going to help.

I think to start:
1. Pull fairing off
2. Check plug - for crud and wetness
3. Check oil for gas and change oil or if looks/smells OK, still change oil when we get it to fire up.
4. Turn off gas at tank or pinch off fuel lines. Try to start bike with just what is in the carb. If it does start and run until carb empty, probably stuck floats.

If no go, then will have to pull carbs for a cleaning.
......edit: CARB singular, it has one cylinder so should be easy.

Could be as simple as the valves needing adjusted. Or the idle / pilot jet being clogged, and it's pumping too much gas into a cold cylinder to fire.

Probably right on carbs. With 1000 miles, valves are probably OK and considering was running perfect before 3 months of sitting - probably carbs.

[weedahoe]

If the fuel is going through and not being burned, is there any spark?

[crzydood17]

If it has 1 carb... its not a ninja 250.... 250s are Twin water cooled bikes.

[adidasguy]

Haven't had time to look - he just said it was single carb. It is 2 cylinder.
Now back to the issues.....

He SAID there was spark. It would be funny if he did something and didn't put the spark plug wires back on correctly.

Maybe I should pretend it is a GS500 with different fairings and do what I'd do with a GS to get it running? I should ignore everything he said EXCEPT that it sat for 3 months (now 5 months).

[weedahoe]

I was doing something with mine one and left one of the plug wires off and thought something was really wrong when it didnt run right. It can happen

[adidasguy]

I couldn't resist. Had to look at it.

fairings: a real pain in the tukus to take off. GS500 is so simple.
Spark plugs: What a long kludge of a spark plug "shaft".

Did the logical: pinched off the fuel line to the carbs. WOW! gas all over the place. Something pumps gas into the air box. It must have a fuel pump?

The air box was full of gas and pouring out all over the place.

Opened up the air box - loaded with gas and soaked air filter.

Noticed tank was now about empty and gas gauge said empty.

Tried again. It started! Ran smooth. ANY throttle kills it. Still lots of gas in the air box. I have the air box open and filter out so it can get some air.

Quitting for the night so all the spilled gas can dry up. Also cold.

Now to wait for the manual. Study the fuel system and figure out why this thing is flooding itself. With the gas line pinched, unless there is a fuel pump, no gas should go anywhere.

If there is a pump, then are we down to stuck floats in the carbs or something else?

I think I am close. Just waiting now for the service manual.

GOD I HATE WORKING ON A KAWASAKI!

SOOOOOOOO glad I chose the GS500 over the Ninja 500.


Anyway, while I wait for the manual, who knows the fuel system on the Ninja? maybe I can easily (yea - like anything is easy on a Ninja?) errr.... get it fixed.


An After Thought:
Is the floats in a Ninja mechanical or a switch for the fuel pump?
It seems that if I pinch off the fuel to the carbs, gravity or pressure would stop fuel flow and not fill up the air box.
However, if the floats in the Ninja were an electrical switch that turns the fuel pump off (or an electrical valve), then it would explain all the fuel getting forced into the air box.

[adidasguy]

I was doing something with mine one and left one of the plug wires off and thought something was really wrong when it didnt run right. It can happen

So does this mean you know the Ninja fuel system or are you talking about a different bike?

[dam]

No fuel pumps on any carb bikes that I know of.
This may help:
http://www.kawasakipartshouse.com/oemparts/#/l/kaw/500b6574f8700223e4797664/2010-ninja-250r-ex250jaf-parts
or
http://www.kawasakipartshouse.com/oemparts/#/l/kaw/500b6578f8700223e47976a2/2010-ninja-250r-ex250jafa-parts

[jestercinti]

After reading through this, I'd recommend a top to bottom carb clean and float height check.

I bet gummed up carbs are causing the floats to stick, thus causing gas to go all over the place (i.e. in the airbox).

Yep, had a Ninja 500 once for the wife.  Hated it.  A b!tch to work on.

[TonyKZ1]

You can also try over at the Ninja 250 site as there's a lot of info on the new gen (08-12) and old gen (86-07) too for that matter Ninja 250s over there. But with the fuel running into the engine, it sounds like there's crap/dirt/? in the carb's float valves letting the fuel run into the engine. Also for the USA market new gen 250, it's carb'd and doesn't have a fuel pump. However the oversea models are fuel-injected.
Tony

[dam]

~ with the fuel running into the engine, it sounds like there's crap/dirt/? in the carb's float valves letting the fuel run into the engine.

That's what I was thinking.

[adidasguy]

Well, stuck floats IF they work like GS500 floats can't be it. If they operate a switch to a fuel pump then maybe because.....

If I punch off fuel from petcock to the carbs as done here


The air box fills up with fuel really fast. and that just can't happen with gravity fed fuel if the line is pinched off.
So I will have to research the fuel delivery system when the service manual arrives later this week. There was snow on the high hill of West Seattle today so I drove the car.


I was told that nothing was done to the bike except change the oil. This really looks like a fuel line and a vacuum/air line got reversed. What could make the air box fill up with gas when the line to the carbs is pinched off?

...and why do you need water cooling for a 250cc motor? That's just silly.

[adidasguy]

(I joined and posted on the Ninga forum. Their message board is not as nice but DOES allow uploading pictures)

A fresh thought: Could it be a torn diaphragm in the fuel petcock? Torn so the vacuum to turn the fuel on is really sucking fuel into the carbs? I can pinch off that vacuum line and try with more gas in the now empty tank.

[BockinBboy]

Could try hooking up a temporary gas tank to eliminate everything before the carbs.  Just be sure its higher than the carbs.

- Bboy

[adidasguy]

Have the MotionPro shop tank. Looks like the tank should be popped off anyway since the carbs should be cleaned.

Ninja forum suggested floats stuck for a couple months could have filled crankcase with gas and now it is blowing gas through the breather. However the airbox has clean gas - not oily.

I will check the oil level. What is odd: with the fuel line to carbs pinched off, more gas went into the air box. So I still have a bad feeling about the petcock.

So:
1. check oil level
2. remove petcock and its vacuum line from the equation

[xunedeinx]

If you pinching the line, and it has a pump, its a evap return system with a stuck one way valve, letting gas into the air box, and not only vapors...

I think.

Just rebuild the carbs and rip off the emissions junk.

[jestercinti]

Oil overfilled?

Edit: Not oily gas in air box?  Agree with Xune. Rebuild and clean carbs. Change oil. Retry. Should fix.

Hose routing diagram.