On 10 May 2006 04:55:42 -0700, "Cokey" wrote:

Hi,

I hope this is the right group to post this question to - I couldnt
find a lawnmower specific group.

I have just purchased a Flymo XL500 petrol lawnmower. Upon starting it
for the first time yesterday, I noticed that for the first second or
two it makes a kind of knocking noise - as if the blade was slightly
loose or something. It also makes the same noise when stopping. While
running normally, cutting the grass, the noise is not there at all -
only very briefly when starting and stopping the engine. I checked it
over thoroughly underneath and everything is nice and tight. The noise
was probably coming from the engine itself. Maybe this is completely
normal? I previously had a Flymo L400 - a smiliar mower but much older
and with a different engine. No such noise from that (although it runs
much louder than the XL500)!

So does anyone else have the XL500? Do you get this same, slight
knocking noise when starting and stopping and is it normal?

Many thanks
Marc.c

Do you know the make and model of the engine, which would facilitate a
Google search for details?
Manufacturers have incorporated various features for easy starting and
stopping which include modified camshafts, decompressors etc. It could
be something like that coming into operation when starting and
stopping.