We've come a long way from the days of black smoke rolling out the exhaust pipe of our diesel powered equipment. We will soon be taking delivery of a new John Deere mower fleet, but have taken Jerry Pate Turf up on their offer to provide us with current-spec mowers to evaluate. The machine above is a 4500-D rough mower with the new USEPA Tier IV compliant power unit from Yanmar. The 4500, and its big brother 4700, have been the class of the field for a few years now, and for the most part the basic machine has not changed outside of the requirements of the new powerplant.
The Tier IV requirements are so strict that the new engines need to employ several components to acieve compliance. Combustion chamber conditioning is accomplished with high pressure common rail fuel injection, turbocharging, and cooled exhaust gas recirculation. Exhaust after treatment consists of a catalytic converter and particulate filter. Engine management is by Bosch, and interfaces with other contol units on board via CAN bus.
All the manufacturers have approached the packaging the same way with the exhaust aftertreatment above the engine, close-coupled to the turbo outlet. Toro and Deere are using Yanmar, while Jacobsen went with the Kubota option.
Pros: Plenty-O-Power from the Yanmar, Hydraulically driven cooling fan can reverse direction to blow chaff off of radiator screen, typical 4500 productivity.
Cons: Control interface is a bit clunky compared to the Deere unit's auto-throttle, same deck/roller issues, my favorite planetary drives...
A grinder from Bernhard that can spin and relief grind.
Those who remember the old single-blade Foley units will see more than a couple of similarities. While I was eventually able to grind 13 QA5 reels (with outstanding finished product) the machine simply takes far too long to set up and run compared to the competition.
The indexing mechanism is driven by this 15mm stroke linear actuator. The blade guide/side cover has been removed here. The blade guide pivots on the same axis as the wheel, and when the actuator cycles the blade guide is allowed to drop out from under the blade.
Indexing completion is registered by applying blade pressure through the guide finger mechanism to this cam, which became fouled with grinding swarf after seven reels, necessitating the disassembly of the mechanism for cleaning.
This is the reduction gearbox and adjustable slip clutch which drives the reel for relief grinding. I am familiar with this type of slip clutch, which has been used by SIP for some time now...
Not a demo - we get to keep this stuff - our Eaton hydraulic supplies arrived from Lawson. We are setting up a crimper and fitting inventory to start making our own hoses. Progress...