In the collapsed position the driveline should be approximately 2″ from bottoming out to prevent possible damage to the tractor or implement. When the PTO is in the maximum extended position, the ideal minimum overlap of the two halves should be approximately 6″ (see Fig. A).

If determined that the driveline is too long, follow these procedures for adjusting the driveline to the correct length: separate the two drive line halves. Connect one half to the tractor PTO and the other half to the implement. Raise and lower the machine with the three point hitch to find the position where the driveline is shortest. Hold the half shafts side by side and mark the desired length on the outer female guard tube leaving a 2″ gap between the end of the guard tube and bell guard. Cut off both guard tubes the same amount as marked (see Fig. B).

Shorten both drive tubes the ¬†same amount as guard tubes. De-burr and clean filings from drive tubes and apply grease to outside of inner tube. Reassemble the drive line halves and connect to tractor and implement. Raise and lower implement again to be sure drive line does not bottom out in shortest position and has a minimum overlap of 6″ in the longest position.

PTO min max
mower blade maintenance and replacement
Caution: Carefully file away the drive line operator’s manual supplied by the manufacturer. The following does not substitute the information found in the drive line manual.
mower blade maintenance and replacement
Caution: Always work with the drive line as straight as possible. This will prolong its life and that of its components. It is advised, not to work at an angle greater than 15 degrees.

Additional resources

ADMA (Agricultural Driveline Manufacturers Association). ADMA’s mission is to promote increased safety awareness in regard to the design, operation, and maintenance of agricultural drivelines. To achieve this objective, our primary focus is on developing educational materials that address these goals with the hope of reducing farm related injuries in North America.