Rm 125 Water On Plug Will Not Crank. Help!!

[joshctr]

OK,

I kinda got this free with the cr 500 I bought. It seems like it wants to crank, but I pull the plug out and there a greyish bubbles on the plug. I thought it was a blow head gasket, I took the head off and the gasket looked fine. I changed it anyway. The bike has compression. What do you guys think, I am not sure where to look. Like I said you can kick it over a couple of times and there is water gas and looks like a bit of oil on the plug. I left the plug in for about 2 weeks with out messing with it and the whole plug was white and crusted when i pulled it out. This is a nicew bike I would love to get it running, help help help

 

[joshctr]

Anybody?

 

[digifox]

Maybe its leaking coolant into the cylinder?
But that would cause the cylinder walls to rust.

 

[julien_d]

Maybe its leaking coolant into the cylinder?
But that would cause the cylinder walls to rust.

No, not unless it has been sleeved. Aluminum and plating do not rust.

We had some water coming into a KTM we were working on through the base gasket, so you might check that. A leak down test would help find something like that. Have you drained the tank and carb and tried with fresh gas? Perhaps there's water in the gas?

 

[kawraper]

Are you sure its water and not fuel?

 

[rmc_olderthandirt]

If it had a blown head gasket at one time it may have leaked a significant amount of water down into the lower end. Until that water is all gone it will interfere with the engine running. If the water has been sitting down there for weeks it may have caused damage to bearings.

What I would suggest would be to:
1) remove the gas tank.
2) remove spark plug.
3) turn the bike upside down, let it rest on the handlebars/seat
4) turn the engine over and see what comes out the sparkplug hole.

Rod

 

[joshctr]

Thanks guys. I am sure it is water/coolant mixing in with the gas. Those are some good points. I will start by flipping the bike over and drain all fluids. The gas tank has already been drained, and fresh gas is in it. Keep them coming., if the head or cylinder was cracked how do i find that? it does have compression. Also when I changed the head gasket everything looked normal.

 

[joshctr]

Maybe its leaking coolant into the cylinder?
But that would cause the cylinder walls to rust.

Nmae the ways it can leak collant indo the cylinder? My first thought was head gasket, but I changed that. What other ways?

 

[NoSlowBike]

Nmae the ways it can leak collant indo the cylinder? My first thought was head gasket, but I changed that. What other ways?

Cracked head or cylinder.

Phil

 

[julien_d]

^^^And that just about sums it up. Have you removed the pipe and drained it out? If the head gasket did leak, and the pipe is full of water, it can be pulling it back into the cylinder.

 

[joshctr]

Sounds like I just need to take it all apart.