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Here's one for the "guru's"

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Ok so i have a 08 crf250r. It has always ran like a champ ( hondas ) and recently, its been actin weird because i havent rode it in a while. When i try to start it, gas leaks from the tubes comin' out of the bottom of the carb. it wont kickstart cold because of this i think. But when its warmed up ( started by push starting it,) i kill it then start it with hot start and it fires right up.

So now the real problem, some of you might think im a dumbass, but heres whats wrong. I left it idling hoping to run a quarter tank through the carb with all that carb cleaner and, left it un-attended. I come back out an our later and, i hear this weird noise, i look in the gas tank and there is bubbles (air) flowing from the bottom. I try to kick it and get the nastiest burnt smell i've ever smelt. I try to push start it today and it wouldnt even start. Look at the oil (lucas oil) and its the clear/black color and low. The radiator hose that drains off the bottom of the bike is burnt.

Please help i am completely dumbfounded.

Any thoughts would help.

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I'm guessing that you were draining out the oil when you noticed the color of it. My best guess is the clear is probably coolant and the black is burnt oil. There's probably severe bearing and ring damage along with other stuff. Severely overheated is an understatement! That engine is going to need a lot of work.

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Just for future reference to others. YOU CANNOT LET THESE BIKES SIT AND IDLE FOR EXTENDED PERIODS OF TIME! There is not a radiator fan to cool the engine coolant. Im guessing the head is warped beyond belief. Like the others said this engine is going to need some serious love.

Why didn't you just drain all the gas and drain the float bowl to keep it from sitting with gas in it?

Sorry, not trying to sound like an ass but these are the cold hard facts.

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Unless you put a fan in front of the bike you overheated it severely. Not real sure how oil can be "clear/black" at the same time...

Lucas Oil is usually clear you know? and know its like someone dumped dirty burnt oil in there without mixing them together if that makes any sense.

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Ray it sounds like originally the float needle was stuck. As for the ending it is as bad as everybody is telling you.

Does the oil smell burnt as well?

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Just for future reference to others. YOU CANNOT LET THESE BIKES SIT AND IDLE FOR EXTENDED PERIODS OF TIME! There is not a radiator fan to cool the engine coolant. Im guessing the head is warped beyond belief. Like the others said this engine is going to need some serious love.

Why didn't you just drain all the gas and drain the float bowl to keep it from sitting with gas in it?

Sorry, not trying to sound like an ass but these are the cold hard facts.

BECAUSE IM A DUMBASS AND LOVE SPENDING MONEY!!!? So is there just some parts i should buy? For the 08 crf250r i always hear the "bad valves" rumor so should i replace those? How much is a new head, and to have it put it in? If there is boring involved.

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Just for future reference to others. YOU CANNOT LET THESE BIKES SIT AND IDLE FOR EXTENDED PERIODS OF TIME! There is not a radiator fan to cool the engine coolant. Im guessing the head is warped beyond belief. Like the others said this engine is going to need some serious love.

Why didn't you just drain all the gas and drain the float bowl to keep it from sitting with gas in it?

Sorry, not trying to sound like an ass but these are the cold hard facts.

Ray it sounds like originally the float needle was stuck. As for the ending it is as bad as everybody is telling you.

Does the oil smell burnt as well?

beyond burnt :lol: and the oil level is barely on the dipstick, i checked it prior and it was between the top and middle.

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I'm guessing that you were draining out the oil when you noticed the color of it. My best guess is the clear is probably coolant and the black is burnt oil. There's probably severe bearing and ring damage along with other stuff. Severely overheated is an understatement! That engine is going to need a lot of work.

no i wasnt draining i just examined the dipstick.

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No way to know what you will need without a tear down and inspection.

As stated above the head is likely warped. I just went thru trying to have a head milled and it was a disaster, I ended up replacing the head. If you are replacing the head then new valves would be a good idea.

Other main components that may have been damaged are the cylinder and crankshaft. The crank will be the difficult one to determine what the heat did to it, but if you get everything above it repaired and it lets go you are doing the entire job again plus splitting the cases.

After my overheat I did not replace the crank but I am looking at the oil filter very close after every ride.

Sorry about your mishap but you will learn a lot from it.

Rooster

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No way to know what you will need without a tear down and inspection.

As stated above the head is likely warped. I just went thru trying to have a head milled and it was a disaster, I ended up replacing the head. If you are replacing the head then new valves would be a good idea.

Other main components that may have been damaged are the cylinder and crankshaft. The crank will be the difficult one to determine what the heat did to it, but if you get everything above it repaired and it lets go you are doing the entire job again plus splitting the cases.

After my overheat I did not replace the crank but I am looking at the oil filter very close after every ride.

Sorry about your mishap but you will learn a lot from it.

Rooster

so if the head is warped, can i get it bored? then just put a bigger piston in there? It sound pretty expensive to do all this if everything is broke i might just consider getting a new one in a year or two :lol:

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Have you checked to see if you boiled all the coolant out? IF there was coolant still in the engine, there may be some hope for the lower end, crank, cylinder, piston. Rings are definitely shot, head may not be warped, and I suspect even the valves may be OK. Note, however, that the exhaust rocker cam follower bearing is usually the first to go in the top end. They don't tolerate low oil or overheating and you can only replace the entire assembly.

You will need to go through every bearing and seal to check for roughness and if one of the radiator hoses is melted, I would also replace the entire set... They get brittle when super heated.

Major bummer on the deep fat fry of your engine, but they are rebuildable with the proper deep inspection.

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Have you checked to see if you boiled all the coolant out? IF there was coolant still in the engine, there may be some hope for the lower end, crank, cylinder, piston. Rings are definitely shot, head may not be warped, and I suspect even the valves may be OK. Note, however, that the exhaust rocker cam follower bearing is usually the first to go in the top end. They don't tolerate low oil or overheating and you can only replace the entire assembly.

You will need to go through every bearing and seal to check for roughness and if one of the radiator hoses is melted, I would also replace the entire set... They get brittle when super heated.

Major bummer on the deep fat fry of your engine, but they are rebuildable with the proper deep inspection.

Ya it will be a month or three before i get it fixed because ( being a junior in high school)... im broke as a joke! But i might go tear my bike down here in a few days if it warms up (currently like 9 degrees). I'll get back to all of you of the results and i will post pictures of everything.

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I know you are eager to tear it apart, however in my experience the more time that passes the harder it is to re assemble.

What part of CO are you in?

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I have rebuilt multiple 06-09 CRF250Rs... If you are anywhere near Denver, let me know when you get ready to tackle the project, I may have a few cycle to help out.

And I would also agree that disassembling the engine before you are ready to do the rebuild is not the wise move. You can loose parts if you don't zip-lock bag the parts by sub-assembly and label everything carefully, other wise, you will forget how they all go back together.

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I know you are eager to tear it apart, however in my experience the more time that passes the harder it is to re assemble.

What part of CO are you in?

redvale co

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man that sucks, post pics when you tear down and we will give you some advice

ya it will be awhile but i will be sure too. I definately dont want to pay a dealer 500 bucks for inspecting whats wrong

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