Tuesday, March 25, 2014

Disaster... Averted

Meanwhile, in Frostbite Falls (for those of you who remember Rocky and Bullwinkle)...

When we left off, I was leveling the ice with the Olympia. Let me digress for a moment to discuss the primary difference between Olympia and Zamboni: the power transmission system. The Zamboni uses a hydrostatic transmission, like an army tank. You set the engine RPM's to a specified level and a governor keeps it there. That keeps all the hydraulic pumps moving at a consistent speed. The transmission uses a lever, the further the lever is pushed, the faster it goes. On newer Zamboni's the foot pedal is also a transmission control, not a throttle control like a car.

So, the lever is used to set the "top speed" and the pedal is used to control the speed in the same way as a throttle, even though it is controlling the transmission. Most of the time I just throw the lever all the way forward. When you let off the pedal, since it cuts off the hydraulic flow, the machine stops and all four wheels are essentially locked. So it is like the opposite of a "Neutral" setting, it is an "All Stop."

Olympia, on the other hand, uses a standard automobile automatic transmission. The stick goes through the regular P-R-N-D-2-L gears just like a car. The pedal is a throttle control, just like a car. The augers that move the snow are variable speed, they go faster as the pedal is pushed to increase throttle. They use larger auger blades to handle the fact that some snow might build up when you let off the gas to go around a corner and speed back up when you get back on the gas.

While resurfacing, you put it all the way down into Low gear so the transmission is not trying to shift gears upward and downward while resurfacing. That would get really interesting, and it not a variable you want going on. But, there is some variation. They key to how an automatic transmission works is the torque converter. This link explains how it works.  You really don't notice when you are driving a car, you push the gas and the car goes.

But, if you have ever pulled a heavy trailer or a boat, or just had your car really loaded down, you might have noticed how the engine winds up a bit before the wheels start turning. That is the torque converter winding up enough power before the wheels start. The Olympia goes through a similar process and repeats the process during resurfacing, like when speeding back up after slowing down to go through a turn. I could feel the wind-up a few seconds before the thing speeds back up.

Well, on one particular pass, while shaving fairly deeply, I experienced this. Or, so I thought. It was not so much the transmission as it was I had totally clogged the conditioner with snow to the point that the augers would not turn. I bogged down and the wheels were spinning on the ice, studded tires and all, digging down into the ice. I gave it more gas because I just thought it was the transmission. I mentioned before, I am "at one" with a Zamboni, sort of a Zen thing. Not so much with the Olympia, yet.

It took me a few moments before I realized what was happening. Also, as I was sitting in one place, the water was flowing. Water flowing and machine not moving is bad. the water can burn straight through to concrete and I was fumbling with the levers to get it shut off. Lucky for me, I did get the water shut off and the tires did not cut all the way down to the ice paint.

Phew! I got really lucky. I limped the snow-stuffed Olympia off the ice and finished the cut with the Zamboni. This would be no problem, right?

Wrong.

I went out with the Zam and began cleaning up the slush piles I left from the Olympia. Fat, dumb, and happy, things were going great. Then, the motor began to stall. Out of propane. No problem, this happens. It's why there are two propane tanks. One runs out, you throw a switch and draw off the other tank. I confidently threw the switch and "vroom" the engine started back up.

Then it died. BOTH tanks were empty. Apparently the crew guys who had been flooding the night before ran out of gas, switched to the other tank, but never replaced the one that was empty. They left me in the lurch. HOWEVER, I do not blame them. I should have done my full pre-use inspection of the Zamboni. I had not done the full inspection because I was using the Olympia. My fault that I ran out of gas on the ice.

But, I had the same problem, water burning down to concrete is a concern. Luckily, I was able to shut off the water and raise the conditioner off the ice before I completely stalled. But, even with the water shut off, what is in the pipe still drips and can burn to concrete. Of course, this happened when nobody was around. I ran at break-neck speed down the Cyclones tunnel and grabbed a carpet runner from the hallway and drug it back and laid it out under the conditioner to block the direct-dripping of water.

Then I removed one of the propane tanks and tossed it over into the Cyclones bench. Then I ran back to the garage where, luckily, a full spare tank was available. They are typically kept outside in a locked cage, but there was a spare inside. Then I ran with it out to the ice, set it down on the ice, and ran pushing it to the Zamboni where I could hook it up and get going again. 

The machine started right up and I began cleaning up the new mess from the stalled Zamboni. Of course, just as I had everything under the control, help arrived. Murphy's Law, eh?

The cut was finished and the ice was restored for Cyclones use for last weekend's games.

Up next, Olympia blade replacement, adjustment, and machine use for NCAA prep.

Cheers!

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