I want to sharpen the cutting blade on the petrol mower ( Briggs and
Stratton engine/Lawnflite SP mower ) but how do I lock the engine so
that I can remove the nut that holds the blade in place ?

Thanks
Brian

wrote in message
ups.com...
I want to sharpen the cutting blade on the petrol mower ( Briggs and
Stratton engine/Lawnflite SP mower ) but how do I lock the engine so
that I can remove the nut that holds the blade in place ?

Thanks
Brian

You can get a gadget that replaces the spark plug to lock the piston etc.
However, IIRC the nut/bolt that retains the cutter is sometimes of left hand
thread.
In either case a ring spanner of good fit and a sharp blow from a mallet *in
the right direction* should do the trick.
Also IIRC, some mowers have the direction of removal marked upon the head of
the nut/bolt.
HTH
GS

on 11/01/2007, supposed :
I want to sharpen the cutting blade on the petrol mower ( Briggs and
Stratton engine/Lawnflite SP mower ) but how do I lock the engine so
that I can remove the nut that holds the blade in place ?

You should not need to. Isolate the ignition, to make sure it cannot
start - pull the plug cap off. Then use a well fitting ring spanner get
the engine on compression and give the spanner a clout with a mallet.
Be aware that these bolts are usually of a thread which tightens in the
opposite direction to the blades normal rotation so it cannot unscrew
itself in use.

--

Regards,
Harry (M1BYT) (L)
http://www.ukradioamateur.co.uk

wrote in message
ups.com...
I want to sharpen the cutting blade on the petrol mower ( Briggs and
Stratton engine/Lawnflite SP mower ) but how do I lock the engine so
that I can remove the nut that holds the blade in place ?

Doesn't one hold the blade, obviously taking care to not hold it in such a
manner as it can hurt you? (can't remember how I did mine though).

cheers,
clive

On 11 Jan 2007 13:53:34 -0800, wrote:

I want to sharpen the cutting blade on the petrol mower ( Briggs and
Stratton engine/Lawnflite SP mower ) but how do I lock the engine so
that I can remove the nut that holds the blade in place ?

Hold the blade?

--
Cheers
Dave. pam is missing e-mail

wrote in message
ups.com...
I want to sharpen the cutting blade on the petrol mower ( Briggs and
Stratton engine/Lawnflite SP mower ) but how do I lock the engine so
that I can remove the nut that holds the blade in place ?


There is a way, if you are prepared to go to the trouble of making it (for
present and future use):
Make a "piston stop".
Using an old spark plug, remove the insulator and central electrode (brute
force is probably required). Then find a piece of rod (of suitable length)
that will be a _tight fit_ in the body of the spark plug. Brazing it in
would be better, but not essential.

Sylvain.

Thanks
Brian

wrote in message
ups.com...
I want to sharpen the cutting blade on the petrol mower ( Briggs and
Stratton engine/Lawnflite SP mower ) but how do I lock the engine so
that I can remove the nut that holds the blade in place ?

Ignore the ideas of a "Piston Stop" as I have seen the results from others
when they give too much pressure (Usually in the wrong direction of rotation
for the LEFT HAND nut) which results in a holed piston.

Use a piece of 2"X4" timber wedged across the end of the blade against the
casing (Care to be taken if the casing is plastic) to restrain the blade
from rotating.
NOTE
If you turn the engine.machine upside down or further than 90 degrees to
work on it expect some difficulty restarting after the oil has gone past the
rings and into the combustion chamber. Had many a Greenkeeper find out that
a restricted compression piston being pulled by a pull start results in very
sore fingers at the T piece pull start when it locks or kicks back ;-)

Harry Bloomfield wrote:
on 11/01/2007, supposed :
I want to sharpen the cutting blade on the petrol mower ( Briggs and
Stratton engine/Lawnflite SP mower ) but how do I lock the engine so
that I can remove the nut that holds the blade in place ?

You should not need to. Isolate the ignition, to make sure it cannot
start - pull the plug cap off. Then use a well fitting ring spanner get
the engine on compression and give the spanner a clout with a mallet.
Be aware that these bolts are usually of a thread which tightens in the
opposite direction to the blades normal rotation so it cannot unscrew
itself in use.

In other words, the nut is loosened in the same direction as the blade
rotates.

It's much better to free the nut by impact than by hauling on the
spanner, but for maximum impact the blade needs to be held against a
really solid stop like a C-clamp over the grass skirt. That also give
you a hand free to keep the spanner from flying off.

If you think the grass skirt couldn't stand it, that mower is not worthy
of your DIY skills.


--
Ian White

In article om,
Dave Liquorice wrote:

Hold the blade?

Yes. Fit the spanner on the nut so that there
is a slight angle between it and the blade, and
squeeze the two together.

I have a vague memory that Soddes Law says that
(for undoing) you have to fit the spanner angled
just behind the blunt edge and squeeze gripping
the sharp edge.

--
Tony Williams.

wrote:
I want to sharpen the cutting blade on the petrol mower ( Briggs and
Stratton engine/Lawnflite SP mower ) but how do I lock the engine so
that I can remove the nut that holds the blade in place ?

Thanks
Brian

If its like my old Hayter, you don't..hold the blade steady and do the
impact thing on the nut. Its keyed to the shaft..
If its a tapered fit to the crank, you are in doggy doo.

Robbo wrote:
wrote in message
ups.com...
I want to sharpen the cutting blade on the petrol mower ( Briggs and
Stratton engine/Lawnflite SP mower ) but how do I lock the engine so
that I can remove the nut that holds the blade in place ?

Ignore the ideas of a "Piston Stop" as I have seen the results from others
when they give too much pressure (Usually in the wrong direction of rotation
for the LEFT HAND nut) which results in a holed piston.


Or a bent conrod.

Use a piece of 2"X4" timber wedged across the end of the blade against the
casing (Care to be taken if the casing is plastic) to restrain the blade
from rotating.
NOTE
If you turn the engine.machine upside down or further than 90 degrees to
work on it expect some difficulty restarting after the oil has gone past the
rings and into the combustion chamber. Had many a Greenkeeper find out that
a restricted compression piston being pulled by a pull start results in very
sore fingers at the T piece pull start when it locks or kicks back ;-)

Thanks all, if it's just a "jam the blade" type job then no problem !
*( touch wood)*

Brian

wrote in message
oups.com...
Thanks all, if it's just a "jam the blade" type job then no problem !
*( touch wood)*

That explains why it's blunt - wooden blades won't work terribly well :-)

cheers,
clive