Hydraulic Lock

In an internal combustion engine, the cylinder/piston is a closed space. The piston rises in the cylinder, compressing a gas/air mixture until the sparkplug fires, expanding the gas, pushing the piston.

Hydraulic lock occurs when one cylinder is filled with a liquid. The piston, trying to rise in the cylinder, contacts the liquid and cannot move. The engine feels like it is locked up. That's what happened to my Goldwing engine. Somehow, probably the carburetor stuck open, and raw gasoline drained into the downhill pistons while the bike set up overnight. When I tried to start it the next morning, the piston hit liquid, couldn't move, and stopped trying. I thought the engine was mechanically locked, but it was only a liquid lock. A hydraulic lock. It's fixed, now.

I asked my mechanic if hydraulic lock is a common problem in the GL1500. He says he's never heard of it. We both agreed that it was a common problem of the GL1100 series. I drove one of those for two years and it was a common phenomenon to get on the bike and find it locked up. If you didn't turn off the petcock, gas was likely to drain into one of the downhill pistons.

That takes a load off my mind. And, with gas running at $3.00/gallon, it makes more sense to be on the bike than in the pickup. If I need the pickup I have it, if not, then the bike will do just fine.