FM-78 · Y-blades

THE BUYING PERSPECTIVE

Know before you order.

• This is the fixed FM-78 black/Y variant, SKU FM-78-0007. It is separately offered from the fixed hammer variant ending -0006 and the hydraulic H model.
• Current manual printed p40 / PDF p41 specifies 30–65 PTO hp for Y-blades. The hammer version has the same 30–65 PTO hp range; no lower Y-blade minimum is documented for this size.
• Actual cutting width is 70 inches. The FM-78 model number is not cutting width.
• The manual counts 22 Y-blade sets. The page counts 44 Y pieces and separately mentions 22 center blades. Current manual p31 shows left, center and right components in each Y assembly. Confirm complete replacement-kit contents; do not compare sets, outer pieces and individual hammers as equal units.
• The page explicitly says mowers purchased with Y-blades and hammers are not interchangeable. Buying an additional blade kit is not authorization to convert the mower. Current parts tables reuse a standard-rotor part label across diagrams; confirm the exact supplied assembly rather than inferring a conversion path.
• Manufacturer guidance points Y-blades toward grasses and hammers toward saplings up to 1 inch. This is a stated use distinction, not proof of cut quality, throughput, fuel use or performance under particular material conditions.
• The current manual describes Y-blades as reversible and gives a left/center/right assembly order; hammer blades require the stated orientation. Follow delivered instructions and matched-set balance requirements; no service-life or maintenance-cost saving is calculated.
• Fixed placement is listed as 33 inches left and 46 inches right from center. These extents are not verified cutting-edge reach or an adjustable travel range. No hydraulic side shift is fitted to this fixed model.
• Manual generic product weight is 880 lb; page mower-only weight is 710 lb plus a separate 39 lb shaft; shipping is 900 lb. None identifies a complete Y-specific operating load, so complete operating weight remains unverified.
• Use 540 rpm at the tractor PTO. The 2,160 rpm figure is rotor speed, not PTO input.
• Included slip-clutch PTO shaft and gearbox oil do not remove tractor-specific shaft, clutch, hitch and ballast checks. Quick-hitch accessories and bushings are separate order decisions.
• The general machine image it does not independently verify the installed Y rotor or supplied accessories.
• Current manual allows Cat 1 or Cat 2 with a Cat 2 bushing set, while lower page Hitch Type text says Cat 1. Confirm the delivered mounting parts; Cat 2 quick-hitch compatibility is not established.

Published specifications

Power requirement

30–65 PTO hp · Y-blades only

Rear PTO

540 rpm

Three-point hitch

Category 1 / 2

Cutting width, inches

70 inches

Unit weight

Complete Y-configuration operating weight is unverified. Current manual p40 gives 880 lb generic product weight without shaft/oil or blade-specific inclusion. Page gives 710 lb mower-only plus 39 lb shaft and separately 900 lb shipping. These bases conflict or lack scope; none substitutes for an assembled Y operating load.

Hydraulics

Fixed offset; current manual explicitly lists no hydraulic side shift. No rear-remote circuit is required for an offset cylinder. The tractor three-point lift remains necessary; do not copy hydraulic H-model flow, pressure, valve or travel requirements.

Accessories & setup

Page includes a 1-3/8-inch six-spline PTO shaft with slip clutch and gearbox oil. Cat 1 quick-hitch and quick-hitch bushings are separate add-ons; page excludes John Deere iMatch. Cat 2 mounting requires a bushing set per the current manual; inclusion is not confirmed. Verify shaft length, overlap, clutch setup, exact geometry and delivered parts.

Specifications are manufacturer-published, not measured by Acreage Equipment. A shipping weight is not treated as operating weight.