Use caution to ensure that the bracket does not pre-load pump/P.T.O. mounting
The most common power take-off in use is the sidemounted PTO, there are also models installed to the rear of specific transmissions and split shaft PTOs that are mounted by removing a section of the vehicle’s main driveline.
Rear-mounted PTOs are often called countershaft PTOs but many sidemounted PTOs are also driven by gears on the transmission’s countershaft. You may hear people refer to side countershaft and rear countershaft power take-offs to make a distinction. The transmissions commonly found in class 4 and larger vehicles will have provisions for the PTO installation.
Generally there are two apertures, one on each side of the transmission(some smaller transmissions may have one). Many Eaton Fuller transmissions have a PTO aperture on the bottom (offset to the left), and some Allison automatic transmissions have a top aperture.
Your Chelsea PTO may be engaged by a cable, lever, air pressure, or hydraulic pressure. Recent PTOs use a small electric motor and hydraulic pump inside the shift cover assembly to provide hydraulic force to engage the PTO. There are various output shaft configurations available for a driveshaft connection or the pump attachment, directly to the PTO, without an intermediate shaft. The Society of Automotive Engineers (S.A.E.) has established standard mounting face dimensions for pumps and PTOs are made to accept these. These are referred to, from smallest to largest, as the S.A.E. A, B, D, E and F