I got an OS 160 FX and also bought the Perry Oscilating pump (not battery powered), I was informed that I need to tap a hole in the backplate for this pump to work. Anyone got any comments or experience with this sort of pump? Am I better off with a battery powered pump? Thanks.

Wilson,


The Perry Oscillating Pump does not need a hole drilled anywhere.
It is simply mounted on the engine; preferably by the top two back-plate bolts.

It is operated by the very small movement (adjustable) of its pumping element, due to the engine's power pulses.
In other words, the engine, by vibrating operates the pump.

The Perry Pump Regulator does need a hole drilled in the engine's crankcase, or back-plate and a pressure fitting installed, since it operates by utilizing the crankcase pressure changes, or pulses, to move its pumping element back and forth.
It is not have to be mounted on, the engine, or the mount.

This regulating pump will not work well with air-bleed carburettors.


Battery powered pump??? Who makes one? How does it work?

Dar ... oooops ... my mistake!!! Its a regulating pump. I thought Perry Pumps used a battery to power it! Hahahaa ... I guess that the OS160FX is not an air bleed carb ya ... hehehe ...

The oscillating pump won't work with air bleed carbs either. Both deliver fuel above atmospheric pressure, which means the excess fuel will flow out the air bleed and you will always have a rich idle.