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Dang 04 wr250f just won't start

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I bought this bike not running since it was dirt cheap. Now I know why it was so cheap... I like to think I'm good with my hands but I can't get this thing to turn on for the life of me. So now I'm going for a hail marry play hoping you guys can help me before I throw in the towel and take it to the shop.

I cleaned the carb

new battery

New gas

Shimmed the valves

checked the timing

changed the oil

New spark plug and there is spark

I even changed the water pump bushings since it was getting water into the oil

Reassemble everything and the damn thing still won't turn on. It doesn't even sound like if it wants to. I press the electric start and it just cranks and cranks but no dice. I checked the kick lever and it does have compression. My dad and as far as taking out the spark plug and adding a tiny bit of fuel in there and putting the spark plug back in. Hit the power button and nothing. It just cranked and cranked.

Could it be electrical? Could it be something else? Should I just take it to a mechanic? Or should I just take it to the woods and shoot this thing?

The good thing is I have learned a lot along the way!

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I also tried disconnect the cut off switch to make sure it wasn't stuck.

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An engine needs compression, fuel & spark (at the correct time) to run. When I (quickly) check a no start I have a can of carb cleaner & a spark checking tool in hand, spark plug laid on head works ok.. Spray carb cleaner in the intake... Still no start I install the spark checker and look for spark. If both fuel & spark are present I go deeper. I check the actual compression & verify ignition pick up / timing marks.

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I have an 04, one of the best in my fleet, son has it now.

^^ what KEEN said.

If you haven't, put a new sparkplug in since your old one COULD be fuel fowled.

 

Before screwing it in, connect it and ground it to metal and button the starter to see if you get spark.  If so, move on to carb.

I assume spark is in time, but its possible a sheared Woodruf key will have it out of time.

 

Next is check carb settings and adjustments.  The slide could be all the way down, which would prevent it from starting so check idle screw adjustment.  Should be .8mm clearance under the slide,  about the size of a .8mm mechanical lead pencil which is not much, but with the carb out, you should be able to see light under the slide.

Fuel screw should be about 2 turns out +- some depending on your pilot jet.

Pilot jet should be a 40 but may need cleaning or replaced if totally clogged.

Leak jet controls the accelerator pump squirt and is in the bowl.  You can check operation with fuel in the bowl and twisting the throttle to see if fuel squirts out of the spray bar in front of the throttle slide.

There's a lotta stuff out there on carb adjustment, you can search on my ID for 100 leak jet info for a couple of threads.

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If you have compression, spark and fuel it should start.

 

Every once in a while mine would schit the bed and not start.

 

I'd try a new plug and opening up the air box, pull the air cleaner out and spray starting fluid in.

 

Then quickly put the air filter back in a try kicking it or jump starting it.

 

When a bike sits for a while the pilot jet and circuit can get clogged.

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Well looks like I just found a new surprise... I went to tinker with it today some more. I checked the radiators and they were empty. Looks like now I also have to add new top end gaskets to the list .. I'll check the piston and rings while I'm in there

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cheap doesnt always mean spending less money....

 

hope the surprises stop there. i wonder what story the previous owner gave you... i bet he knew exactly what happened.

 

buying a non-running bike is like buying pandora's box. you never know what you're going to find, and usually its the worst. Top end is no big deal, i agree, but past that it starts to get tedious and you wonder why you're working instead of riding. Sounds like you're a competent driveway mechanic. You got this. Good luck!

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I'd check for the easy fix first, and hope that its just a water pump seal.

Look at the oil and see if its got water in it... milky oil.

Then check the hoses for cracks or splits.

If none, then yes, top end... head gasket is likely.

 

I think I'd still try to get it fire  ... but that's just me. 

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So of course I dig a little deeper and find some more problems. The head gaskets were done just as I expected but I also found a surprise. After all, what's life without a few surprises along the way?

The cylinder and piston have suffered some damage. I plan on buying a top end kit that comes with new gaskets as well as a new piston. Now for the cylinder, can it be fixed/plated or do I have to replace it? Would I be better off going with a big bore kit or something along those lines? I would prefer to keep it as close to stock as possible.

NCM_6163.jpg

NCM_6164.jpg

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There are some companies out there that do replating and will exchange which is what I would go with.  Buddy of mine likes one of the snow mobile builders in mid west... cant remember the name right now.

 

Nothing like knowing that stock Yamaha parts will fit when you need something.  You can do a big bore too but rejetting and tweeking will be in your future.  This engine is already over square by a large amount (like putting a 350 top end on a 175 stroke) so my opinion is you loose some of the bonus of you go further.  Its your money.

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Re-plating is what I would prefer to do. Does anyone happen to know and reputable companies that can do this in Southern California? The closer to Los Angeles the better. If not, which companies do you guys recommend I ship my cylinder to?

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I saw the prices and turn around times of re-plating vs new cylinder and looks like new it is! Ended up going with a kit that includes piston, rings, cylinder, gaskets and all that other fun stuff for a top end rebuild. The kit should be at my front door by next Friday at the latest!

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IT'S ALIVE!!!!

 

The new piston and cylinder showed up  at the doorstop on Tuesday so I rushed home and got to work. Changed all the gaskets, slapped in the new piston with the new rings as well as the new cylinder. I started to reassemble everything and making sure I wasn't missing anything since it had been a week since I last touched this bike. I made sure the engine was at TDC and triple checked my timing. I closed up the motor and called it a day.

 

Last night I put the carb, tank, seat, and all that fun stuff back on. She was fully assembled...then there was a moment of silence. I looked at my dad and he looked at me. I didn't want to push the power start for fear of it not starting. I told him to do it but he insisted that I do it. I pushed it once and this time it ACTUALLY sounded like if it wanted to turn on. Pushed it again and it was about to turn on but I let go of the button a little too early. Then on the third time, because everyone knows third times a charm, BAM this damn thing really did turn on!!!!! I looked at my dad and we both had the biggest smiles on our face. My dad fine tuned the carb and she's purring like a kitten! I'm so pumped right now. I'm still on a natural high!

 

The only thing to do now is multiple oil changes to get the left over water out of the motor. I also have to adjust the slack in the chain and tighten up the front brake.

 

Hopefully I can brake her in on Sunday :ride:

 

This has been a love hate relationship but I am finally a happy camper!!!!

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I tried doing a search but couldn't find anything on oil filters. Since I am going to be doing quite a few oil changes to get all the water out from the oil, can I remove the oil filter throughout this entire process? Meaning, remove the oil filter and place the cover back on so the engine is sealed. Then I would let it idle and change the oil over and over until it comes out clean. Once it's clean I will drain that oil, replace it with good oil, and slap a brand new oil filter in there.

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I tried doing a search but couldn't find anything on oil filters. Since I am going to be doing quite a few oil changes to get all the water out from the oil, can I remove the oil filter throughout this entire process? Meaning, remove the oil filter and place the cover back on so the engine is sealed. Then I would let it idle and change the oil over and over until it comes out clean. Once it's clean I will drain that oil, replace it with good oil, and slap a brand new oil filter in there.

I would not run it without a oil filter. If any trash is in the oil it would end up in the head. You don't want that!!

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On Saturday I was able to completely get all the water out of the engine oil. On the third draining of the oil it looked 100% clean :cheers: Filled it up for the fourth time. Meanwhile, between each oil change, I was doing the standard break in procedure since I had installed the new piston and cylinder. On Sunday my dad, bro, and I went to the desert for a quick morning ride. As soon as I got there I was able to complete the standard break in procedure. Let the bike cool down the rode it like normal for the rest of the day. This bike rode like a champ with no issues aside from needing to be re-jetted.

 

I am way happier with this wr then I have ever been with the yz! I'm loving the Cadillac soft suspension and the magic button :thumbsup:

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Also, thanks to everyone that helped me along the way. The cool thing is that every time I typed a question into google it always brought be back to TT.

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