Height of CUT Adjustment, Other Adjustments

HEIGHT OF CUT ADJUSTMENT

DANGER To assure safety, disengage the engine clutch lever, remove the ignition key, and disconnect the engine spark plug

wire prior to making any of the following adjustments.

1. STANDARD ADJUSTERS

The height of cut is variable and may be adjusted on both wing cutting units and the rear cutting unit by loosening the top and bottom Adjusting Nuts (A) which hold Roller Adjusters (B) in Roller Brackets (C). Roller (D) may then be moved up and down.

It is important to get all rollers adjusted to the same height so that there will be uniform cutting across the entire width of the cutting unit. Do not adjust by sight. Place the mower on a hard, level surface and place a board or gauge plate of the desired height under each bed knife back bar. Allow the rear roller to rest on the level surface. Retighten the adjusting nuts and remove the gauge plate or board.

STANDARD HEIGHT ADJUSTER

NOTE: Guards removed or cut away to show detail

NATIONAL 68 SR & DL TRIPLEX

2. DIAL-A-HEIGHT ADJUSTERS (OPTIONAL)

To set the height of cut, lift the vinyl cap and socket (A) off the adjuster tube. To raise the height of cut, turn the socket clockwise (viewed from above). To lower the height of cut, turn the socket counterclockwise. Each quarter turn (90°) of the socket will raise or lower the height of cut by approximately 1/32". A full turn (360°) will raise or lower the height of cut approximately 1/8".

When making large adjustments (over 1/2"), make small adjustments to each side until the desired change is reached. When the desired height is achieved, lower the socket and make sure the adjuster tube locks it in position.

The scale decal (C) on the rear side of the adjuster indicates the height of cut. To use it, sight along the bottom edge of the adjuster tube (B). The reading on the scale is your approximate height of cut.

You should determine the exact settings by test mowing your turf. If very accurate cutting heights are required, place the cutting units on a hard, level surface and place a board or other gauge plate of the desired height under each bed knife backing bar. Lower the rollers to the level surface. When completed, make sure the socket is locked in position over the adjuster tube.

DIAL-A-HEIGHT ADJUSTER (OPTIONAL)

OTHER ADJUSTMENTS

For other machine adjustments, see the Maintenance section of this manual.

68OM-06/03

68 SR, 68 DL specifications

The National Mower 68 DL and 68 SR are two outstanding models in the world of lawn care, engineered for efficiency and ease of use. Both mowers offer a range of features tailored to meet the needs of both residential and commercial users, making them popular choices among landscapers and homeowners alike.

The National Mower 68 DL is designed with durability and performance in mind. It features a robust steel deck that enhances longevity while providing a clean and even cut. Equipped with a powerful engine, the 68 DL delivers high torque and swift acceleration, enabling users to tackle even the toughest grass and rough terrain effortlessly. The mower's advanced cutting system ensures that grass is cut finely and evenly, reducing the need for additional clean-up.

On the other hand, the National Mower 68 SR offers a self-propelled option, allowing users to move with ease across various landscapes. This model incorporates hydrostatic transmission technology, which provides smooth, variable speed control. This feature is particularly beneficial for those who demand precision in their mowing tasks, as it allow for adjustments on the fly, catering to changing terrain conditions.

Both models come with adjustable cutting height options, offering users the flexibility to choose their desired grass length. The easy-to-use lever enables quick and simple adjustments without needing tools, making the mowing process more efficient. Additionally, both the 68 DL and 68 SR are designed with ergonomics in mind, featuring comfortable handles and intuitive controls that minimize operator fatigue.

Safety is another critical consideration in the design of the National Mower 68 series. Both models come equipped with protective shields and safety switches to prevent accidental starts, ensuring that users can operate the machines with confidence.

For convenience, the mowers also feature large, easy-roll wheels that enhance maneuverability. The inclusion of a bagging system offers an option for collection of grass clippings, contributing to a cleaner lawn appearance post-mowing.

In summary, the National Mower 68 DL and 68 SR combine advanced engineering with user-friendly features that prioritize performance and safety. They are exceptional choices for anyone looking to maintain a pristine lawn with minimal effort, making yard work a more enjoyable task. Whether for home use or professional landscaping, these mowers stand out in their class, delivering reliable performance time after time.