Max-Prop V.P. Fast (3 & 4 Blade) — Instruction Manual

Installation

• Supplied assembled for right or left rotation, with the pitch set at order if it was discussed. Parts are NOT interchangeable: with more than one propeller, never swap parts.

1. Fit the propeller onto the shaft like a fixed propeller. A properly fitted key has almost no side clearance and a very small clearance on top, so a key that is too tall cannot push the propeller off centre.
2. Tighten the nut and secure it with the two Allen head screws.
3. Fill the propeller with the supplied marine grease through the holes marked "GREASE" using the supplied grease fitting. The central body must be completely full, with grease oozing from the rotating joints. Use only a grease approved by Max-Prop.
4. Move the blades into the feathered position with the rounded trailing edges aft (Fig. 2).

Before Launching

• Hold the propeller shaft and check that the blades rotate freely from forward to reverse with a light effort.
• In the feathered position the blades must be perfectly lined up.
• Confirm the propeller body is full of grease.
• Protect the propeller from galvanic corrosion with sacrificial anodes on the propeller and on the shaft.

Pitch Adjustment

A critical step: know the pitch to set, from your old propeller or from the engine and reduction ratio.

Fig.3: pitch in inches for each blade angle (rows) and propeller diameter (columns). Size diameter and pitch as for a fixed propeller, find your diameter column, go down to the pitch you need and read the blade angle across.

• Blade angle is adjustable from 10º-30º in one degree increments; each degree changes engine RPM by 6% - 7% at the same boat speed.
• If the engine does not reach the desired RPM, reduce the blade angle; if it exceeds it, increase the blade angle.

Setting the Regulation Ring (Fig. 4)

1. Remove the set screw from the hub reference hole.
2. Pull the regulation ring towards the bow and turn it to increase or decrease the blade angle for your rotation.
3. Line up the hub reference hole with the number on the ring for the chosen angle and rotation. Two screws in the threaded holes of the ring give leverage.
4. Let the ring snap back in place, then lock it with a set screw in the hub reference hole.

Changing the Rotation

• Rotation is judged from the stern looking forward with the engine in forward: clockwise = right hand "R", counterclockwise = left hand "L".

1. Unscrew the zinc screws and remove the zinc.
2. Unscrew the nut locking screws and remove the nut.
3. Remove the circlip at the aft edge of the hub and pull the zinc bearing ring aft.
4. Rotate the ring so the "L" tooth (left-hand) or "R" tooth (right-hand) lines up with the hub reference mark, and push it back in place (Fig. 5).
5. Refit the circlip, tighten the nut and secure it with the locking screws, and refit the zinc with its 3 screws.

Propeller Use

• The propeller works automatically: put the transmission in gear and the blades engage in forward or reverse; they feather from the forward position when you stop the engine and lock the shaft.
• Best way to feather: power at 2 to 3 knots in forward, then kill the engine while still engaged in forward. A properly greased propeller feathers in a fraction of a second once the shaft stops freewheeling.
• Do NOT kill the engine in reverse: the blades stay in the reverse position and cannot feather. You can use this to drive a shaft alternator.
• Mechanical transmission: stop the shaft freewheeling by engaging reverse, only after the engine has stopped completely.
• Hydraulic transmission: shut off the engine while still engaged in forward; the remaining hydraulic pressure locks the shaft for a few moments, enough for the propeller to feather.

Never shift between forward and reverse at high RPM. Idle down and shift at low RPM, or the shock load can damage the teeth of the blade gears and cone gear.