Checking Engine revs with an Electronic Tacho
If you want to know how many revs your engines are running at, this can be checked with the use of an electronic on board Tacho. The Tacho stores the maximum revs achieved during a run, this figure can be checked when the boat is brought back to the pits. The Tacho resets itself by running the engine at lower revs for a few moments before throttling up to full speed. Readings for straight drive or your gear ratio can be pre-programmed into the Tacho. The magnetic pulse for the sender is generated by a small magnet fitted into an aluminium collar that is grub screwed to the shaft, or it can fitted directly into the base of an aluminium coupling of a straight drive boat.

 

 

 

 
The Tacho itself can be mounted wherever is convenient, I have made removable brackets that use the same bolts as the gearbox or engine mountings, I have put the Tacho inside a small plastic box to keep it dry, the box fixes to the bracket with Velcro. It is easily fitted and then removed when testing is complete.

 

 

 

Copyright R Daniel