[Colin Stamp]

Hi all,

Ebay recently provided me with an old Hayter Harrier 56 lawnmower,
sporting what Hayter call a "Blade Brake Clutch". I've never had a
petrol mower before, so I don't really know what to expect, but the
first cut didn't go as well as I'd hoped. The engine kept bogging down
whilst mowing but it was particularly bad whilst engaging the cutter.
Even If I tipped it up so the blade was well clear of the grass,
engaging the cutter would momentarily load the engine to a near stall.

At the weekend, it wouldn't start at-all and seemed not to have too much
compression. I started to take the head off today and discovered that
all the head bolts were finger tight except one, which was missing.
Coincidentally enough, the head gasket looks like it's been blowing for
some time...

Inside, it doesn't look too bad. The bore and valves all look OK to my
never-seen-inside-a-mower-engine-before eyes. Hopefully a new gasket and
bolt should see the engine back to reasonable performance, but a quick
test of the blade brake and clutch makes me think that was part of the
problem too.

I can easily spin the engine by hand with the cutter drive lever at
either end of its travel, but there's a patch in the middle where the
engine gets very difficult to turn. Obviously, the blade brake is still
on when the clutch starts to engage. It seems wrong - I would have
thought that the brake would release first and then the clutch would
engage. Then again, perhaps it's normal, to prevent a free-wheeling
blade, and a working engine should easily overcome the momentary load.

What does the jury think? Should I fiddle with it?

Cheers,

Colin.

[Muddymike[_2_]]

Hi all,


What does the jury think? Should I fiddle with it?

Cheers,

Colin.

I have a Hayter 56, its a good machine, mine copes well with all sorts of
grass and a lot more, it's well worth fiddling with. I have never had to do
more than replace the blade so can't advise.

Mike

[NT[_2_]]

On Apr 2, 8:03*pm, Colin Stamp wrote:
Hi all,

Ebay recently provided me with an old Hayter Harrier 56 lawnmower,
sporting what Hayter call a "Blade Brake Clutch". I've never had a
petrol mower before, so I don't really know what to expect, but the
first cut didn't go as well as I'd hoped. The engine kept bogging down
whilst mowing but it was particularly bad whilst engaging the cutter.
Even If I tipped it up so the blade was well clear of the grass,
engaging the cutter would momentarily load the engine to a near stall.

At the weekend, it wouldn't start at-all and seemed not to have too much
compression. I started to take the head off today and discovered that
all the head bolts were finger tight except one, which was missing.
Coincidentally enough, the head gasket looks like it's been blowing for
some time...

Inside, it doesn't look too bad. The bore and valves all look OK to my
never-seen-inside-a-mower-engine-before eyes. Hopefully a new gasket and
bolt should see the engine back to reasonable performance, but a quick
test of the blade brake and clutch makes me think that was part of the
problem too.

I can easily spin the engine by hand with the cutter drive lever at
either end of its travel, but there's a patch in the middle where the
engine gets very difficult to turn. Obviously, the blade brake is still
on when the clutch starts to engage. It seems wrong - I would have
thought that the brake would release first and then the clutch would
engage. Then again, perhaps it's normal, to prevent a free-wheeling
blade, and a working engine should easily overcome the momentary load.

What does the jury think? Should I fiddle with it?

Cheers,

Colin.

The way you think makes far more sense, and sounds like the problem on
that side.

The bolt arrangement says to me there's something serious the last
person didnt bother to fix - but perhaps its just the brake mechanism,
you never know.

I trust you'll sharpen up the blade, mowers run much better when its
kept sharp, and drink less.


NT

[Colin Stamp]

On 02/04/12 21:17, Muddymike wrote:
Hi all,


What does the jury think? Should I fiddle with it?

Cheers,

Colin.

I have a Hayter 56, its a good machine, mine copes well with all sorts
of grass and a lot more, it's well worth fiddling with. I have never had
to do more than replace the blade so can't advise.

Mike

That's encouraging. The only thing that disappointed me about it was the
lack of engine power. Even in that state, it showed the lawn who was
boss. Hopefully the new head gasket will sort it out...

Cheers,

Colin.

[Colin Stamp]

On 03/04/12 00:21, NT wrote:
On Apr 2, 8:03 pm, Colin wrote:
Hi all,

Ebay recently provided me with an old Hayter Harrier 56 lawnmower,
sporting what Hayter call a "Blade Brake Clutch". I've never had a
petrol mower before, so I don't really know what to expect, but the
first cut didn't go as well as I'd hoped. The engine kept bogging down
whilst mowing but it was particularly bad whilst engaging the cutter.
Even If I tipped it up so the blade was well clear of the grass,
engaging the cutter would momentarily load the engine to a near stall.

At the weekend, it wouldn't start at-all and seemed not to have too much
compression. I started to take the head off today and discovered that
all the head bolts were finger tight except one, which was missing.
Coincidentally enough, the head gasket looks like it's been blowing for
some time...

Inside, it doesn't look too bad. The bore and valves all look OK to my
never-seen-inside-a-mower-engine-before eyes. Hopefully a new gasket and
bolt should see the engine back to reasonable performance, but a quick
test of the blade brake and clutch makes me think that was part of the
problem too.

I can easily spin the engine by hand with the cutter drive lever at
either end of its travel, but there's a patch in the middle where the
engine gets very difficult to turn. Obviously, the blade brake is still
on when the clutch starts to engage. It seems wrong - I would have
thought that the brake would release first and then the clutch would
engage. Then again, perhaps it's normal, to prevent a free-wheeling
blade, and a working engine should easily overcome the momentary load.

What does the jury think? Should I fiddle with it?

Cheers,

Colin.

The way you think makes far more sense, and sounds like the problem on
that side.

I odered a new head gasket today from a small firm and spoke the the
owner about it. Apparently he's seen quite a few Hayters with blade
brake clutches and "they all do that sir". I think I'll get the engine
back to something like its intended power and see how it copes before I
try adjusting anything.


The bolt arrangement says to me there's something serious the last
person didnt bother to fix - but perhaps its just the brake mechanism,
you never know.

Yep. That is a bit of a worry. Ever the optimist, I'm hoping the last
person to "service" it got distracted or something. There's nothing
obviously wrong looking at the top end. The valves seem to be seating ok
and the bore looks pretty smooth. The new head gasket is on order, so
I'll find out soon...

I trust you'll sharpen up the blade, mowers run much better when its
kept sharp, and drink less.

Yep. It's a bit knarly, so I'll be getting out the angle grinder...

Cheers,

Colin.

[Muddymike[_2_]]

On 03/04/12 00:21, NT wrote:
On Apr 2, 8:03 pm, Colin wrote:
Hi all,

Ebay recently provided me with an old Hayter Harrier 56 lawnmower,
sporting what Hayter call a "Blade Brake Clutch". I've never had a
petrol mower before, so I don't really know what to expect, but the
first cut didn't go as well as I'd hoped. The engine kept bogging down
whilst mowing but it was particularly bad whilst engaging the cutter.
Even If I tipped it up so the blade was well clear of the grass,
engaging the cutter would momentarily load the engine to a near stall.

At the weekend, it wouldn't start at-all and seemed not to have too much
compression. I started to take the head off today and discovered that
all the head bolts were finger tight except one, which was missing.
Coincidentally enough, the head gasket looks like it's been blowing for
some time...

Inside, it doesn't look too bad. The bore and valves all look OK to my
never-seen-inside-a-mower-engine-before eyes. Hopefully a new gasket and
bolt should see the engine back to reasonable performance, but a quick
test of the blade brake and clutch makes me think that was part of the
problem too.

I can easily spin the engine by hand with the cutter drive lever at
either end of its travel, but there's a patch in the middle where the
engine gets very difficult to turn. Obviously, the blade brake is still
on when the clutch starts to engage. It seems wrong - I would have
thought that the brake would release first and then the clutch would
engage. Then again, perhaps it's normal, to prevent a free-wheeling
blade, and a working engine should easily overcome the momentary load.

What does the jury think? Should I fiddle with it?

Cheers,

Colin.

The way you think makes far more sense, and sounds like the problem on
that side.

I ordered a new head gasket today from a small firm and spoke the the owner
about it. Apparently he's seen quite a few Hayters with blade brake
clutches and "they all do that sir". I think I'll get the engine back to
something like its intended power and see how it copes before I try
adjusting anything.


The bolt arrangement says to me there's something serious the last
person didnt bother to fix - but perhaps its just the brake mechanism,
you never know.

Yep. That is a bit of a worry. Ever the optimist, I'm hoping the last
person to "service" it got distracted or something. There's nothing
obviously wrong looking at the top end. The valves seem to be seating ok
and the bore looks pretty smooth. The new head gasket is on order, so I'll
find out soon...

I trust you'll sharpen up the blade, mowers run much better when its
kept sharp, and drink less.

Yep. It's a bit knarly, so I'll be getting out the angle grinder...

Cheers,

Colin.



Take time to balance the blade after sharpening. Nothing fancy required,
just stick a pencil or the like through the bolt hole and see if one end is
heavier than the other.

Mike