An old kawasaki dx250f won't start

Hello first I'd like to clarify some things, I have no experience in dirt bikes but always wanted one so a couple of years ago I bought 2004 (as the seller claimed) kawasaki kdx250 I wanted to get into dirt bike and it seemed like a good bike, anyway when I got the bike it was in working condition so I went out and tried it, works great. I got it back home and a couple of days later tried to start it it won't start.
So I took it to the shop and got it fixed took a ride near the shop to check if it works it was fine they said it only needed new spark plug which the seller told me it might.
I loaded it up and took it home a week later I took it out for a ride with a friend loaded it poorly on its side (didn't know any better) and when I got there I tried to start it and it won't start. So I got back home frustrated and disappointed I left it in the back of the house and it stayed there.

Fast forward 2 years I decided to see if I can fix it so I started reading online here is what I've tried so far:
I thought it might be flooded since the gas was turned on for 2 years. So I checked the the gas in the tank still smells like gas and feels like one so I didn't change it. The oil looked new to so I topped it off. And I also changed the coolant. There is more to be done but I just want to see if I can get it to work. And it didn't.
I pulled the carb out and cleaned it the flote was stuck so I checked the needle valve and it looked good and the pilot jet was clogged so I cleaned it. Reseated the needle valve and floaters they function as they should. The I put the carb back in place (the only things connected were the air intake, engine intake, the gas tube, and the thing that comes from the throttle) . After that I tried to start it and it won't.
So I took the spark plug out to check if it sparks and it was very wet with something black clearly not oil I cleaned it and tested it and it does spark (a blue spark). I put it back in and tried to start ir it doesn't start.
Now my only guess is maybe the compression is bad but I don't know how to test that. Even though 2 years ago it was working so I don't think it's an engine proplem.

There is a couple of things that I have no idea what is there function:
1 there is a tube coming out of the connection between the carb and the engine connected to nothing.
2 and there is a green tank right under the gas tank which seems to have oil but I didn't mess with it.

Any ideas how to proceed from here. My motivation is taking a nosedive right now, and I've decided before starting this if I could fix it by myself I'll keep it if take it to the shop I'm selling it and never look back.
I'll upload some photos when I can.
 
Here are some photos.
And as far as my research I think it's 1992 but not sure there is no vin number but there is some engraved characters where the vin is usually that say Dx250f-009532
And a stiker on the frame with "model dx250f" written. 20191216_153926.jpg20191216_153943.jpg20191216_154004.jpg20191216_154029.jpg
 

SRAD97750

Moderator
Staff member
Welcome, sorry to hear of your troubles.

Looks like you are on the right track.
Compression readings are taken from the spark plug hole with a compression tester, available at most auto parts stores and harbor freight.
I suspect after sitting for so long the fuel is 100% bad. I would dump it, especially if It's premixed.

Fresh fuel and clean the carburetor again, it's a fueling issue most likely. -BIG DAN:thumb:
 
Welcome, sorry to hear of your troubles.

Looks like you are on the right track.
Compression readings are taken from the spark plug hole with a compression tester, available at most auto parts stores and harbor freight.
I suspect after sitting for so long the fuel is 100% bad. I would dump it, especially of It's premixed.

Fresh fuel and clean the carburetor again, it's a fueling issue most likely. -BIG DAN:thumb:
Thank you I'll try it tomorrow.
Any idea what is that green tank for?
Or the tube coming from the engine intake?
 

SRAD97750

Moderator
Staff member
OK, I am going to guess this is from another country, we never had any KDX250 models with that tank or hose on the intake, in the USA. Nor can I find any info on them.
At this point I have to guess it's actually a oil injection system.
Some people disable them and run premixed fuel instead of relying on the bike to mix it for you. The hose should be clamped or plugged in this case.

If it still is a functioning system, there will be a pump, tank, and hose connected to the intake, these would need to be tested for output. -BIG DAN:thumb:
 
OK, I am going to guess this is from another country, we never had any KDX250 models with that tank or hose on the intake, in the USA. Nor can I find any info on them.
At this point I have to guess it's actually a oil injection system.
Some people disable them and run premixed fuel instead of relying on the bike to mix it for you. The hose should be clamped or plugged in this case.

If it still is a functioning system, there will be a pump, tank, and hose connected to the intake, these would need to be tested for output. -BIG DAN:thumb:
Thanks again Big Dan.
I'll clamp that hose and mix my own gas as far as I know the ratio should be 32:1 and any 2 stroke oil should work.
And yes I am from Saudi Arabia ♥️.
 

SRAD97750

Moderator
Staff member
Awesome, keep us updated.
So rarely we get a competent person willing to post actual information that will get them answers. It's nice to have you.

We want to see the riding in SA too! -BIG DAN:thumb:
 
Big Dan s the shnizz as we say in old school America
It sounds like (as new to bikes) you have some research done to this point to have this grasp so far.
Step 1. Want it
Stop 2. Make it happen
 
Do one check at a time .. write down results . Remember , Intake , compression , power , exaust . Start with the basics .. air intake , fuel delivery , compression reading , exaust . Spark ? Spark plug ? Here to help ....
 
Update :
I changed the gas and oil tank and cleaned the carb again. It still won't start.
I'm running out of Ideas here I have gas spark air and the only reason I'm rolling out compression is that the bike worked fine before then it ran out of gas and didn't start again, so it's no likely to be an engine problem right?
Also what causes bad compression does the carb has to do with that tha gasket had a bit of a crack in it?
 
Have you disconnected the kill switch on the bars? Could be shorting or corroded from sitting outside for 2 years. I'd do that and see what happens. A crack in the carb gasket would give you an air leak, but you should still be able to start it. depending on how bad the crack is.
 
Ran out of gas , at wide open throttle , going down a long hill . Made it to the bottom , then just loaded it up and left it behind barn .. was parked there for about 2 yrs . Now won't start ... Heard that . Took it home , took out spark plug . Dry . Add half can of PB Blaster . To stuck engine . Let it sit till next day . Now freed up , continue with other half of PB . Blow out all the crap . Add more PB , check spark , install new plug . Squirt in a little mixed gas , Boom , contact . , It's alive ... clean carb , tank and fuel valve , install new lines . DONE .. Ran that baby almost 2 yrs. ..... sold it running ...... hope you get that lucky ... let us know ....
 
Update :
It turns out after watching a random video on YouTube that I didn't assemble tha carburetor correctly I had the float setting untop of the needle valve not attached to it. Therefore the gas was not getting in.
I fixed that and changed the gasket whit RTV gasket maker and let it set till next day.
Then when I try to start it sounded promising then a very weird sound came from the engine kind like a gun shot not an engine sound I got scared and stopped for a bit. A few minutes later I tried again and it backfired, I said dang it I'll try until one of us die. Full throttle it started properly for a split second and stopped. Somehow I ran out of gas?? I had plenty in there where did it go? Anyway I poured more gas and it turned to be leaking from the carburetor overflow. I tryed to turn it on anyway it only runs in full throttle for a sec. So I knew that my pilot jet is properly clogged. I took the carb out and it was a mess in there the rtv was everywhere. And the float was stuck to rtv I cleaned everything and applied rtv again but in much smaller quantity and I'm waiting for it to dry.
Another interesting thing happened while I was kicking the engine. My bike has a light high and low switch, for some reason I turned high beam on then when I kicked the engine my dash lights would turn (I have three lights in my dash high beam neutral and oil) the neutral and high beam would turn when I switch to low beam none of them light up.

Anyway my motivation just skyrocketed and I can't wait to try it tomorrow.
Also I disconnected the oil injection cause I'm not sure if it works properly.
 
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