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WR250 wont start

19K views 29 replies 7 participants last post by  Vault 
#1 ·
I just bought my 2003 WR250 yesterday (Friday) and ran it down the driveway (slow, I'm a noob) and it ran fine. I woke up today thinking I could get loads of practice in, but came across a major problem. My bike wouldn't start :hmmm:. I then noticed that it was leaking fuel out of the airbox. I guess I left the fuel switch on over night or something. Anyways, the bike wouldn't turn over. I even tried kickstarting it. We suspected a dead battery, so we charged it. Then after a while of charging, it still wouldn't turn over. We tried kickstarting it again, but when we tried the lever would not move AT ALL. Yamaha's have a hot-start thing that releases pressure from the cylinder or something, so I pulled that (keep in mind I am not in anyway familiar with this bike). When we went to start it again, a LOT of liquid spewed out an overflow tube by the foot shift lever. We could not determine if it was gas or some other liquid. So, after looking in the manual, we decide to check the oil. When we looked in what we thought was the dipstick (the oil filler cap) , a mixture of oil and antifreeze poured out. At this point we called the previous owner and he said this kind of thing had never happened before. I looked around online and some people said this happened to them and it was a head or water pump gasket. Hard to imagine that the bike was running fine yesterday, and it wont even turn over today :wtf: If any of you have any idea of what is wrong, I would greatly appreciate it.
 
#2 ·
Sounds like you get to learn how to rebuild a motor. I'd go talk to the guy you bought it from. Probably won't get your money back, but I bet it's been smoking for a while.
 
#3 ·
No, it was running perfect yesterday. I talked to the guy and he said I should bring it in. I would rebuild the motor myself, but I know my dad would take over and forget how he took it apart (does it all the time, LOL). Plus, I'd still have to get all the parts and know what to look for as I take it apart. It would work out better if I brought it to a dealer.
 
#5 ·
start with what you know.

Fuel draining out of airbox.... well its most likely filled your engine as well and thats where all the mystery fluid is coming from. Drain the oil of all fluids. Pull your spark plug rotate motor over to get all fluid out of cylinder and crankcase. That overflow tube by your shifter lever is the crankcase vent and if fluid is pooring out your motor is full of fuel/oil mixture, that hose connects to the top of the valve cover at the top most part of the engine.

It wouldnt crank over since the motor was hydro locked. do the drain the refill with fresh oil, just go get ya some rotella 15-40 from wal-mart 1 gal for 13$ so you can flush the system twice. once you fill the oil make sure the plug is dry, use a soft brush to get rid of any carbon then a lighter to kinda dry off the electrode of the plug. reinstall and try to crank it over. once it fires again run up and down the drive once or twice then change the oil to get any remaining fuel out.

The problem your having is either the float level was stuck open or its set to the wrong height so it wont close the valve when full.

I doubt you have coolant issues based on the scenario you stated. go ahead and drain, plug, fill start. take pictures of what comes out and post up for more help when you do so.

z
 
#6 ·

As you can see, I started to do what proz07 suggested and I drained the oil. When we did, a mixture of gas and oil leaked out at a high pressure for at least 15 sec. I'd say about a gallon of fuel came out the engine. My dad will pick up some cheap oil tomorrow and we'll get to the plug and do what proz suggested. Do I need a special tool to get the plug out and how do I get to it? (keep in mind this bike has an aftermarket 3 gallon tank)
 
#7 ·
Pull the seat, radiator shrouds, and fuel tank. You'll be able to pull the coil plug off then the coil will pull out. Then just a wrench with extension and spark plug wrench.

Z
 
#9 ·
Yamaha's have a hot-start thing that releases pressure from the cylinder or something, so I pulled that (keep in mind I am not in anyway familiar with this bike).QUOTE]

Your bike does have a hot start, but when you pull the hot start lever it allows more air in your intake. It is basically the opposite of choking the bike. A decompression lever releases pressure in the cylinder, which the earlier yamaha fourstrokes did have. Your bike has an automatic decompression on the exhaust cam.
 
#13 ·
Lol, just got the spark plug out (after some frustration :hmmm:) and I used the kick to crank it over. I had no idea that gas was gonna spew out and I got some on my eyes. I can only thanks my science teacher for teaching me to rinse out my eyes. :lol: Do I just clean the plug and put it back?
 
#15 ·
My bad i guess i should have suggested putting a rag over the hole for the spark plug. :anim_peep: But just hit the bottom of the spark plug with alittle brake cleaner and just use some sand paper or a wire brush to get the carbon off the electrode. After that i usually use a lighter heat up the bottom end of the plug alittle bit to burn off some of the additional carb. Be careful though if there is still some brake clean on the plug as it is flammable. Also id check the gap on the plug to make sure it is in spec.
 
#16 ·
Actually, I'm here in Jennings WAYY on the other side of BR. I went look at it last Tuesday and the guy was actually very nice and he seemed like he knew what he was doing. He had two other bikes and he's an engineer from UL.
The bike ran fine when we got home (Friday) after purchasing it. I've already contacted him about this problem, and he said he was sorry and all that. I just hope I can get this all sorted out. :hammer:
 
#17 ·
Spark plug's back in. As I wait for my dad to get home with the oil, is anyone familiar with the Athena 290cc Big Bore kit?
I found this..

hole on the cylinder and I just wanted to make sure it checked out
 
#19 ·
That hole is in the head and its the spark plug drain, so no junk sits in there and corrodes if it gets any water or anything past the coil dust seal.

Z
 
#20 ·
Just got done running it up and down the drive. Smoked a little for a little while, but it cleared up. I'll change the oil again tomorrow after I ride it again. I made sure to close the gas valve and I even ran it till it was out of juice.
Thanks for your help so far guys, you all really helped :thumbup:
 
#21 ·
Not again

So, here I am again with a bike that doesn't run. After I changed the oil, I started it and ran it for a few afternoons. After a while, I notice the battery was getting weak, so I just kickstarted it for the time. I was riding it and I stalled, and it would not start again. I thought I was out of gas, so I topped up. It would not start (still could turn over the motor), so I had my Dad push me and we clutch started it. That worked for a while, until I stalled it again. I kicked it over yesterday, and it started, but there was a horrible *click click* sound while it was running. Now, the battery is completely dead and I cannot kick it anymore. I don't know what to do now. I am highly considering bringing it to a local shop.
 
#25 ·
Then how do you explain it not being able to kickstart or crank?
I was going to get a new battery anyways, and on the connection the previous owner installed a plug in so I don't have to take the seat off every time. All I need to do is pick up a charger or tender.
Any suggested brands for that?
 
#30 ·
Bad news

Just got word from the mechanic I brought the bike to that it dropped a valve and did some serious damage. He said he'd call us back on an estimate to when he should get that all fixed up. He gave us an estimate on the bill :headshake I really wish all this crap didn't happen. All I wanted was to have a fun bike for the summer. :damn: Does anyone have an idea of why the valve dropped?
 
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