Guys Need some help...Have you ever seen this before?

[jprm250]

Guys,

Just finished jacking around with my 05 RM250. I have done more top end rebuilds than I can remember but...I had major problems with this one. This is the first top end since I bought the bike.

Here's what happened....Cylinder went on no problem. got everthing back together...kicked it..ran for a second and died. pulled the plug and found coolant on the plug. no problem.. pulled the top end off and replaced the two oring gaskets.

Put it back together. kicked it same thing again.....did this 5 times before I got pissed and stopped for the night. I know everything is correctly put together. It has compression and will fire until the coolant leaks into the combustion chamber and floods it.

The only thing I didn't do was take apart the exhaust valve. which shouldn't matter....The only thing I know to do (which I have already done) is order another gasket kit. Any thoughts fellas?

Also, I did grease the oring gaskets before installing them like the book says?

 

[skipn8r]

I'm assuming the o-ring seating surfaces look blemish free. I had a blown head gasket (CR250), and the bike ran fine, it just seemed rich. Is it possible you're drawing water into the system at the base gasket?

 

[ellandoh]

i would suspect it spilled into the bottom end while working on it and was unrelated to the gaskets. that is if it was running fine before the work was done and i was reasonably sure of my work.

 

[jprm250]

I doubt I'm pulling coolant from the bottom end. When I cycle the piston there is nothing coming from the bottom stroke of the piston. it only leaks coolant when everything is back together and ready to start. and then there is only enough coolant to flood the combustion chamber. the oring seat is clean of debris and blemish free....the only thing I can think having slept on it last night ....is maybe I over torqued the cylinder cap....any other thought would be appreciated!! thanks guys

 

[sparkysakitas]

sounds like coolantdown in the crank area
happened when i did my rm
take motor out take hed and cylinder off turn upside down and drain it out its probably in your pipe to

 

[sick 96 250]

It sounds like you got coolant in the bottom end like mentioned, i did the same thing before and you can fire the bike up for a second then it would wet foul the plug, let it sit for a little then it would start again and stall because of the same thing. I just drained the coolant, flipped the bike upside down with the plug out and rotated the rear wheel while in gear slowly and coolant came out of the plug hole, then it was fine after that

 

[NO HAND]

I doubt I'm pulling coolant from the bottom end. When I cycle the piston there is nothing coming from the bottom stroke of the piston. it only leaks coolant when everything is back together and ready to start...

It may still be from the cylinder base gasket. It is just normal that no coolant leaks from there when you have the head off the cylinder. It takes the pressure/vacuum from the engine cycle to pull the coolant; which happens only when everything is assembled.

 

[jprm250]

thanks guys.......I guess I'll tear it down again and replace the base gasket, redrain the tranny oil and start again.

 

[sick 96 250]

you dont need to drain the tranny oil, i would flip it over with the plug out and kick it over and see if coolant comes out at all then try to fire it up and see what happens