A.Lee wrote:
The Natural Philosopher wrote:

A.Lee wrote:
My spare lawnmower, a Mountfield, B+S engined SP470 is playing up.
It is revving and slowing, revving then slowing etc.
It is all related to the governor springs/fan, which slow it down when
it is revving too much.
So , the query is - is it viable to do away with the governor and
control the engine speed manually?
Yes, but he main problem is that you will be constantly fiddling was it
runs into different loads.

It sounds like you have some friction in the governor..not just
maladjustmemnt.

No, it is the spring adjustment on the governor. There are 2 springs,
both of which slacken with age, or when messed around with.When viewed
from the side,with the engine running, it is clear that they are too
slack, so I've tightened them slightly, which leads to over revving, so
readjust, and it is too slow etc.
It is a pain to adjust them, as you need to remove the top cover and
starter puller plate to get at them. If they were open, then adjustment
would be a lot easier.
Thanks
Alan.

New springs maybe?