2001 cr250 Motor Damage

[sdryder278]

I recently was given a 2001 cr250 that had been sitting in my buddy's backyard exposed to the elements for about 6 months. Upon inspection it really is not in that bad of shape, just needs some TLC. The problem is that while it was sitting outside there where no radiators or radiator hoses on the bike so water had been getting into the cylinder. I pulled the top end apart drained the little water that is in it and can still see a little sludge build up in the crankshaft. Other than the water problem every other part of the motor looks okay. Im thinking i just need to flush it out real good but am not sure what chemicals to use. Any help would be greatly appreciated.

 

[Backslayer]

Id use some gas is I were u just be sure you put some two stroke oil back on the bearings and the rod. that should cut the sludge, and cant hurt it

 

[bclark001]

how did water get into the cylinder???

 

[sdryder278]

Because there was not a radiator hose on the head......Thanks for the response, i was thinking that or something like Marvels Mystery oil

 

[dirt bike dave]

Because there was not a radiator hose on the head......

You said there was sludge built up on the crankshaft, presumably from the water that got into the cylinder.

FYI, the radiator hoses just feed the cylinder's water passages. Not having the hoses on would not allow water into the crankcase or inside the cylinder bore. Unless there was a gasket leak.

The sludge may be unburned and partially evaporated oil from the premix that was used in the bike long ago. It could have nothing to do with water or radiator hoses.

 

[Rotorranch]

Dirt Bike Dave is correct. :nod: There is no way water got anywhere it's not supposed to be by just having a rad hose removed.

Rotor

 

[whenfoxforks-ruled]

Check the cylinder and head. Put a new crank, piston and ring, and bearings. You will have a new bike! Should be under 400 dollars!

 

[steve.emma]

you say you have pulled the top end apart and seen sludge in the crankcase area. if this is water then you could have a problem with rusty or seized bearings, either the rod or crank bearings. if it turns over ok then they are obviously not siezed but if they have gotton rusty then they could be very noisy and will wear out quickly. however my advice would be to flush the crankcase with some premix then turn it upside down to drain, change the gearbox oil.reassemble the engine and kick it over without the plug in it, then start it and see how it is.
good luck the cr's are great bikes.

 

[sdryder278]

Hey thanks a lot guys! I'll let you know what happens