Check your airbox!

[wildman]

I'm rebuilding a 75 Jackpiner, slowly cleaning parts and inspecting parts. My engine is fragged with a broken piston, bad crank bearings and lunched rod. Looking at the airbox i can see why! The exhaust pipe seam wore a long slit through the airbox into behind the airfilter directly letting sand into the engine. Not only that, the mounting bolts go into the clean side,one was missing. Also, the rear of the box is the inner rear fender, it was pitted pretty good as well as all over the exterior. Lots of cracks where the glassfibre fatigued. I got busy by first powerwashing the whole thing, sandblasted the repair areas, and reglassing the bad spots, there were a lot of them. Then I washed it out again, there sure are a lot of crevices to get into and clean out. I can see its a good idea to grease the inside with white grease to catch and spot any debris. I read that we should always use sealer where the airboot attaches to the airbox, the seams come together right at the airboot flange and are a little uneven. Hope this helps save someones engine. Dan Pagel

1975 250 Cross Country, 1974 175 Jackpiner, 1975 125