The air filter boot on my Banshee tore and it looks like the engine ate a significant quantity of sand on my last dune trip. I have another trip planned for next week. The engine was running fine when I stopped riding. How much damage could I cause if I didn't rebuild it until after the trip? Do I need to rebuild it, or can I run it until it gives up? Thanks in advance for any advice.

 

Well...It's up to your wallet whether or not to let it run until it dies....It could be costly if you have sand scuffing the internals of the motor.
I would think at the bare minimum you should tear down the carb and flush it out completely.
Drain and change the tranny oil just to have a look.
Those 2 things alone should not take more than an hour and could safe the life of your engine.

 

If you have even the slightest feeling that sand got into the motor, I would pull the head and check. Do the cylinder walls feel gritty? Can you catually see sand? Is there sand in the gear saver? If there is, tear it down, clean it, hone it, get new rings, and slap it back together! Good as new, and only a few bucks for gaskets and rings!

 

While you are in there, don't forget to flush out the crank area with oil. Fill and drain a couple of times to get out any sand that might be in there.

 

Good stuff, thanks for the help. BansheeBill, when you say fill with oil, do you mean fill, or put some in and swish it around?

 

Do a compression check first. I agree with bansheeBill if you tear it down swish the cases with a light oil or keroseen until it comes out clean. Good luck. Let me know if you want to go for a ride. My Banshee and Scrambler have been collecting dust all summer. No one wants to ride in the heat.

 

Swish it around and dump it out. Do this until you are satisfied that all the sand is removed. Oil and effort is alot cheaper than rebuilding/replacing the crankshaft.

The point of the exercise is to dislodge and remove any sand that might have worked its way down into the crankcase.