Hi, Joel here at Earth Tools again...since many of our customers (and potential customers) use this forum for reference, I wanted to give an "update" on our experiences with the BCS PowerSafe hydraulic clutch: For starters, there may be some confusion out there as to the nature of this clutching system...it is NOT a "hydrostatic" clutch. It is a oil-immersed, multi-disk flat-plate type clutch, very similar to a motorcycle...the difference being that instead of SPRINGS pushing the multiple disks together, this system uses HYDRAULIC PRESSURE (generated by a hydraulic micro-pump) to press the clutch disks together, which transfers power. When the clutch handle (black handle on the bottom of the left-hand handlebar grip) is squeezed (OR when the red safety lever [above the left-hand handlebar grip] is LET GO) a valve is moved, so hydraulic pressure no longer flows to the clutch plates, and they relax, stopping power transfer.
We have sold a fair number of PowerSafe machines this year, and so far they are mostly performing well. We did have two incidences where customers broke the oil-filter mount off the bottom of the clutch housing when brush-mowing on rough terrain...Funny, when I first saw the PowerSafe units displayed at a trade show in Italy in 2010, I told the BCS engineers that the oil filter was "too exposed" on the bottom of the clutch housing, and recommended that they put a skid plate under it or something. They smiled and nodded, and of course made no changes...what could an American know, anyway? Well, an American knows that not everyone on the planet is using a walk-behind tractor in manicured hayfields and garden plots...in this country, brush-mowing in very rough terrain is common for walk-behind tractors. Luckily, both repairs were fairly minor, about $25 or $30 in parts; the larger problem being that the bolts that were holding the filter mount on were snapped off inside the clutch housing. Luckily both customers managed to get the broken bolts out...otherwise it would have been a very costly repair. I have informed BCS of this problem (again), and hopefully we will see a skid-plate or some kind of additional protection for the filter mount in the future.
I find it interesting that even within my company (Earth Tools), the attitude toward the PowerSafe clutch is changing somewhat on an individual basis... My sales and service managers, for example, tend to favor the PowerSafe systems (especially for customers using high-torque implements) because they know that the system is more "brainless" in terms of being "user-friendly" to persons who really do not understand much about how to use a clutch, period. I must say that with the slow change in generations, is it true (and sad, to me) that many Americans have simply never been exposed to anything but an automatic transmission or a hyrdostatic drive, and they don't have the foggiest notion of how to use a clutch properly. Therefore, when they have to use a machine that has a simple mechanical clutch, they are much more likely to ruin the clutch quickly through too much "slipping" (using the clutch for a speed control, letting the clutch out too slowly, etc.), especially with high-torque, power-consumptive loads like large flail mowers, chippers, etc..
The PowerSafe clutch makes the process of engaging power easier because it builds pressure relatively slowly to the clutch disks...therefore, even if you "drop" the clutch handle, the power to your "load" (large mower, etc.) will engage slowly over about a second or two, so you don't risk stalling the engine most of the time. With a "manual" (purely mechanical) clutch, you have to use your brain a little more to employ techniques to keep from stalling the engine, while at the same time not overheating the clutch (this is no different than driving a stick-shift car or truck). So the PowerSafes are an "easy sell", for this reason.
However, for me personally, at this early stage of selling this system, I am still not convinced of the overall durability of the PowerSafe system...we just don't have the data. Everybody thought DDT was great, too, until they figured out that it was killing entire ecosystems (This is an extreme example, but my point is: we need DATA OVER TIME to prove the ins and outs of any system). Walk-behind tractors are designed to last thousands of hours of service. Until we have PowerSafe clutches out there in the field (not in some controlled test environment) with at least a thousand hours of service with no problems, I am not "sold" on the durability...and there is simply no question that if there DOES prove to be any service issues with the PowerSafe clutches at some point, they are NOT going to be user-friendly to repair, because this is a pretty complicated system; I expect that most repairs would have to go back to a dealer.
With the desire to get more direct use data and experience on this system ourselves, we sold our 7-year-old BCS 853 this Spring and took a new 749 PowerSafe as our "Shop BCS demo tractor".
So, to sum up, I will still say this regarding the PowerSafe: So far, mostly pretty good. If you are a "Techie" and want the latest technology BCS has to offer, fine, go with the PowerSafe (we keep them in stock!), and help us generate usage data. However, if you are more concerned with in-the-field serviceability (and don't mind learning to use a clutch properly, if you don't know how), then the manual clutches are pretty darn well proven on many equipment types over at least 100 years (at least 50 on walk-behind tractors)...on my own personal walk-behind tractor, I had 2000 service hours on the original manual clutch before it needed to be replaced, and many of those hours were operating high-torque implements.
Food for thought...
Happy farming and gardening,
Joel / Earth Tools
