Grains of sand down the spark plug hole

[Greg_M]

Yesterday, while removing the plug to check the valves I noticed what I thought were many grains of sand around the the lip that the plug rests on down inside the engine case. I left the plug loose in the hole to do the valve work until today when I would have access to an air compressor to remove the sand. It sounds stupid now but at the time I figured by the time I removed the plug the damage will have been done.

Well the sand is gone. I either imagined seeing it and there was only a small layer of grime that was still there, or every grain fell into the combustion chamber. I safely removed the grim and proceeded to rock the bike back and forth in an attempt to see any particles. This is nearly impossible to do as the spark plug hole is so small.

Apart from tearing the top end down, what can I do to see if the combustion chamber is clear or not? Maybe I am stuck to just ride it and see what happens unless I want to pay $$$$ to have it torn down?

Any ideas are appreciated.

Greg

[newcastle_brown]

Dude, on the Husky it easy. Just pop off the carb and look down the intake boot...IF the valves are closed just put the end of one of those air blower nozzles in the spark plug hole and blow it out. If the valves are open, try to shine a flashlight to help you see whats down there, had the same problem on an old KTM and got the dirt out with a Q-Tip ?

[mxrider227]

You mite try using some small dia. vinyl tubing(found at lowes or homedepot)attatched to a shop vac and insert it in the spark plug hole with piston at tdc or an exhaust or intake port, i dont think forced air press would be a good idea, you mite force the grains in between the piston and cylinder wall, good luck ?

[Greg_M]

Dude, on the Husky it easy. Just pop off the carb and look down the intake boot...IF the valves are closed just put the end of one of those air blower nozzles in the spark plug hole and blow it out. If the valves are open, try to shine a flashlight to help you see whats down there, had the same problem on an old KTM and got the dirt out with a Q-Tip ?

For one, I have already tried that. Secondly, the air stream will pressurize the combustion chamber, but there is no way the sand will be blown out once it is sitting on top of the piston. At least I can't see how that could happen.

I tried the shop vac thing with a piece of fuel line but I need something narrower I think. Also, this would probably work better with the intake open to get some air flow. With the valves shut and the tube filling the plug hole, there is not much of a way for air to get into the combustion chamber. I'll try one more time tomorrow.

Thanks for the ideas

Greg

[NE14MX]

Just for future reference. The 'drain hole' on the side of the cylinder is present to blow air into when removing the spark plug cap and loosening the spark plug to blow the dirt out first. Use a wire or dentist tool to loosen any stuck dirt before removing the plug. Thats why the hole is present on street bikes which seldom need 'drainage'. NOw about your problem, do you think a couple of kicks with the spark plug out blow the dirt out?

[Greg_M]

Just for future reference. The 'drain hole' on the side of the cylinder is present to blow air into when removing the spark plug cap and loosening the spark plug to blow the dirt out first. Use a wire or dentist tool to loosen any stuck dirt before removing the plug. Thats why the hole is present on street bikes which seldom need 'drainage'. NOw about your problem, do you think a couple of kicks with the spark plug out blow the dirt out?

I'll press the e-start button with the plug out and see if that kicks the stuff out. I am also going to try one more vacumming with some clear tubing down the plug hole and then I'll duct tape the shop vac over the plug hole as well.

If that doesn't do it, nothing will.

BTW, when you start a bike with the plug out, do you have to ground it in some way?

Greg

[YZ250F_Rider]

the sand will clear the cylinder the first exhaust stroke. if it was only a few grains, the chances of damage are minimal.

You can spin the motor by hand until the exhaust valves are open and shove a air compressor into the plug hole. Just blast it a few times and it should push the sand out into the pipe.

[sonorawfo]

Times have changed!!. The plugs nowadays are reseased in the head,(water cooled), and you should always make sure that area is free of dirt. Alittle bit of dirt won't kill the engine, BUT!, it sure won't help!!. ?

[Greg_M]

Thanks all. I liked the idea of setting the exhaust valve to open and then blasting air but it is a little late now.

I got the valves shimmed and put her all back together and fired her up. Everything appears fine and I'll know for sure tomorrow.

Greg