Qualcast Suffolk Punch 35s - ignition spark problem

[paulbedd...@hotmail.com]

Hi

My first post. Hope this is the correct section to post this question.

I've recently gotten hold of a old suffolk punch petrol lawnmower. Was
running ok and was looking forward to using in on my lawn.

Pulled it out of the shed at the weekend and thought i'd give it a
good clean for the season. I decided the best thing to do would be to
spray the engine, in fact the entire mower, in enginer degreaser,
leave it running for a while then pressure wash it. On reflection
probably not the best idea. The old saying goes "if it's not broken,
dont mend it!"

Not long after i'd started pressure washing, the mower cut out and now
has about as much life in it as a dodo!! There is just no spark at the
plug.

I had assumed that water must have gotten into the ignition system and
hoped that if i left it for a few days it would dry out and everything
would be fine and dandy. But no! Three days later and still nothing.

Can anyone help? Do you think i have broken anything or do you think
it is still simply damp and needs more time to dry out? Is there
anything i can do to try and solve the problem or help dry it out? I
have read about megneto coil but not sure what this is?

Any help much appreciated!!

[MikeS]

<paulbedd...@hotmail.com> wrote in message
news:b1174952-fb20-4c72...@t3g2000yqa.googlegroups.com...

Hydraulic lock?
http://en.wikipedia.org/wiki/Hydrolock

[paulbedd...@hotmail.com]

thanks for the response.
Nah, nothing as serious as that.
engine turns ok and compression is good. There is just no spark at the
plug.

[MikeS]

<paulbedd...@hotmail.com> wrote in message
news:0f4cd39a-f100-45ae...@33g2000yqm.googlegroups.com...

I'd start at plug and work back.
Use one from car and see if plug is ok (Unless you have diesel).
Has the lead been damaged/dislodged?
If you start getting into the main gubbings of the engine, personally I'd
bin it. You can get a 4 stroke for £99 nowdays. I got a large self propelled
with Briggs and Stratton engine and clutch online for £119. (Can't remember
the site off hand)...Bargain.

Can I ask the knowledgable folk here - why dont you get a diesel lawnmower?

[paulbedd...@hotmail.com]

Thanks again for you response.
I can see logic in starting at plug. But dont think it is plug as i
didn't pressure was top of engine or anywhere near the plug.
I can't see the entire lead as is goes through a hole into the casing
and not quite worked out how to get to it yet.
Yeah could replace it but its a bit of a challenge now and i want to
get it running again. I bit of a project i guess!!

[Arfa Daily]

"MikeS" <nos...@home.ta> wrote in message
news:SKCtl.77985$Ii4....@newsfe19.ams2...

Too much compression to be able to start with a hand pull ? Need for a glow
plug to preheat the fuel mixture to stand any chance of getting it going ?
Need for a high pressure fuel injector pump ? Low compression petrol engine
with simple carb and magneto-fired spark plug, is simpler all round,
requiring no external power source, and no fuel pump. Easily got going with
a simple hand-pull recoil starter.

Arfa

Arfa

[R]

<paulbedd...@hotmail.com> wrote in message
news:b1174952-fb20-4c72...@t3g2000yqa.googlegroups.com...

Rip off all the covers and look at the generation side of the system.
Odds are there is a dead short there somewhere

http://www.fixed4free.com/answers.php?id=9687

[Tim Downie]

paulbedd...@hotmail.com wrote:

>
> Can anyone help? Do you think i have broken anything or do you think
> it is still simply damp and needs more time to dry out?

I think this is likeliest. Water and HT electrics (particularly on old
machines) don't mix well. I've heard of people using a low oven to really
dry out magnetos.

Possibly a bit extreme but if you can expose the magneto and get some warm
dry air into it, it can't do any harm.

Tim

[Dave Liquorice]

On Tue, 10 Mar 2009 16:41:48 -0700 (PDT), paulbedd...@hotmail.com
wrote:

> I can't see the entire lead as is goes through a hole into the casing
> and not quite worked out how to get to it yet. Yeah could replace it but
> its a bit of a challenge now and i want to get it running again. I bit
> of a project i guess!!

I like that attitude.

Wet has got in (pressure washing engines is not a good idea, water gets
in...) you need to strip it down as much as you can and dry everything.
The ignition module is probably a sealed unit take it off, dry it and put
in the airing cupboard for a few days.

Are you sure you have no spark not a carb or fuel tank full of water?
Water sinks under fuel amd fuel is picked up from the bottom of the tank.

--
Cheers
Dave.

[Dave Liquorice]

On Wed, 11 Mar 2009 02:03:17 -0000, Arfa Daily wrote:

> Too much compression to be able to start with a hand pull ?

You have a decompression lever to release the compression. You pull
several times to spin the engine up on the fly wheel the release the
lever. There is enough momentum to take it through compression and
provided the engine is in reasonable condition it will fire.

> Need for a glow plug to preheat the fuel mixture to stand any chance of
> getting it going ?

Not on my small single cylinder diesel gen set. From cold it's as rough as
old boots for 10 seconds or so producing clouds of white smoke from
unburnt fuel but soon picks up and runs up to speed.

> Need for a high pressure fuel injector pump ?

Driven off the camshaft not a problem.

> Low compression petrol engine with simple carb and magneto-fired spark
> plug, is simpler all round, requiring no external power source, and no
> fuel pump.

Petrol might be a bit simpler but a diesel doesn't need external power and
a 4 stroke petrol as in lawnmower does have a fuel pump to lift the fuel
from the tank, built into the tank/carb unit on my B&S.

--
Cheers
Dave.

[Tim Downie]

Dave Liquorice wrote:

>
> Petrol might be a bit simpler but a diesel doesn't need external
> power and a 4 stroke petrol as in lawnmower does have a fuel pump to
> lift the fuel from the tank, built into the tank/carb unit on my B&S.

Never had a lawnmower with a lift pump before. All mine have had the tank
above the engine. A lot simpler!

I think the main reason for the absence of diesel lawnmowers is weight &
cost. A small diesel engine with the same power output would weight
considerably more.

Tim

[Tim Lamb]

In message <71paioF...@mid.individual.net>, Tim Downie
<timdow...@obvious.yahoo.co.uk> writes

Yes.

Clean the make and break contacts with a bit of fine emery cloth.

Then waft warm air around the ignition coil. Don't overcook it:-)

regards

--
Tim Lamb

[Arfa Daily]

"Dave Liquorice" <allsortsn...@howhill.com> wrote in message
news:nyyfbegfubjuvyypb...@srv1.howhill.net...

I don't doubt that small diesels are out there on things like generator
sets, but they are not particularly suited to use on a lawnmower, for the
reasons that I suggested. Key to getting one to start, is the heavy flywheel
and valve lifter, neither of which are particularly conducive to the thing
being able to be started and pushed, in the case of a non self-propelled
type, for someone of a smaller stature, such as the wife ... ;-)

Also, in good condition or not, I'm willing to bet that the thing can still
be a bitch to start on a cold day. Witness what little diesels like the
Peugeot noddy cars are like when the glowplugs have failed, even with the
help of an electric starter - it used to take the lad across the road fully
five minutes of almost continuous cranking to get his going, before he got
it fixed.

For a standard Qualcast type application, the low revving power of a diesel
is not what is ideally required. Easy-start high revs is what is required.

As far as the high pressure fuel pump being driven off the camshaft, that is
not really the issue. It still needs input power, as it doesn't get the
power to operate for free from the camshaft, so that is additional starting
energy that has to be provided by your arm.

Over the years, I have had several cylinder and horizontal rotary petrol
mowers, in both self propelled and push variations, and they have all been
gravity fed for fuel, with the tank being mounted either up on the handlebar
assembll or, in the case of the rotary that I currently have, directly on
top of the engine, so no fuel pump of any description being required.

Arfa

[meow...@care2.com]

Mowers are normally magneto, which is just a magnet on the flywheel
whizzing past a coil, so no contacts anywhere.

OP is fairly likely to get lucky just by drying it out. 2 or 3 days in
the shed for a semi-enclosed device is nowhere near enough. Expose it
and let it sit a week indoors. If thats impractical, put a warm air
blower on it for a couple of days - be sure not to overheat anything
though.

NT

[paulbedd...@hotmail.com]

Thanks for the responses guys
Agreed, i'll not be pressure washing again. It is clean though!!
Will try and access the electrinic ignition module and get it dried
out.
Problem is that it is located behind the flywheel.
Not sure how to remove that. Difficult to remove the nut in the middle
as the whole thing simply spins around.
Any tips?
Ta

[paulbedd...@hotmail.com]

> Are you sure you have no spark not a carb or fuel tank full of water?
> Water sinks under fuel amd fuel is picked up from the bottom of the tank.
>
> --
> Cheers
> Dave.

Yeah deffo no spark. didn't pressure was anywhere near the fuel tank.

[Arfa Daily]

<meow...@care2.com> wrote in message
news:fbf12c9a-bc8a-41c0...@t3g2000yqa.googlegroups.com...

The magneto fired ones that I've owned have still had points. Accessible
through a hole in the flywheel, normally covered by a plastic insert. One
Qualcast that I owned needed the points to be cleaned every year before
first use, as the contact surface oxidised from the non-use over the winter
period. I guess that the points are there to ensure that the 'charge' - for
want of a better word - that is built up in the coil's core as a result of
the magnet's passing, is 'released' to the plug via the HT section of the
winding, at exactly it's peak, timed to be just before the piston's TDC

Ah... Here ya go. This explains it all nicely.

http://science.howstuffworks.com/question375.htm

or better yet, this one

http://www.foxvalleykart.com/timing1.html

Arfa

[paulbedd...@hotmail.com]

Cheers. I'll have a look, however the mower i have has electronic
ignition. I thought the electronic ignition relaced the need for
points etc?

[gazz]

<paulbedd...@hotmail.com> wrote in message
news:6ce80da0-8b04-408c...@q9g2000yqc.googlegroups.com...

> Cheers. I'll have a look, however the mower i have has electronic
> ignition. I thought the electronic ignition relaced the need for
> points etc?

it does,

the mower engines with points are ancient, villiers and that kind of stuff,

nowadays the spart is generated very simply, magnet set in the fly wheel
edge, and a coil mounted close to the flywheel, as the magnet spins past the
coil, it induces a current in the low tension coil, when the magnet moves
past it, the current is stopped and it fires the spark plug from the HT part
of the coil, it's a nice simple all in one unit, better known as a CDI unit
i believe.

you shut the engine down by shorting a wire out, are you sure your pressure
washing hasnt blasted some insulation off a wire and it's now shorting to
earth? or something like that,

basicaly there will be 2 wires from the coil, big fat one to the plug and a
thin one, that will go to the stop switch, some mowers the stop switch is
built into the throttle, push the throttle lever pash slow and it will make
a contact that shorts the stop wire to ground, this contaft is usually part
of the throttle linkage at the carb.

the earleir sufold punch (before qualcast took over) has a metal tag over
the plug, you pushed that down to contact the ht connection to the plug thus
shorting the spark out.

BTW, re: the small engine diesels, they dont need a glow plug, they are
direct injection, cars like peugeots use indirect injection engines, hence
the need for glow plugs,

with a direct injection engine, it just needs the cold start advance to fire
in freezing conditions, this is usually automatic but could be a lever on a
small gennerator type engine,
and for a pull start, a compression release lever is fitted,

There's nowt hard about starting a pull start diesel engine, slightly
different to a petrol engine, but they are usually fitted to long run
generators where fuel usage is a concern, for a similar sized generator, the
diesel engined one will easily use half the fuel of a petrol engined one,
also they run at a lower speed, so are quieter, and last a lot longer.

Then engine in my motorhome is a direct injection (iveco turbodaily 2.8) it
has a thermostarter, which is an glow plug injector, it's heated up and
diesel is pumped through the plug, the resulting hot fuel is atomized into
the inlet manifold, it's fed with fuel from the spill rail of the injectors,
so no extra pump is needed or owt,

it's totaly automatic in use, will come on when the engine temp is below
freezing, i've camped on the top of a mountian in switzerland in november,
where at night the outside temps dropped to minus 10,
at 09:30 the next morning, i just turned the key straight to start as usual
and she fired right up,

[Arfa Daily]

<paulbedd...@hotmail.com> wrote in message
news:6ce80da0-8b04-408c...@q9g2000yqc.googlegroups.com...

> Cheers. I'll have a look, however the mower i have has electronic
> ignition. I thought the electronic ignition relaced the need for
> points etc?
>

Well, it can do. The primary winding current still has to be switched at the
appropriate time. This can still be done by a set of points triggering a
simple transistor switch. Back in the day, this used to be known as
'transistor assisted ignition'. It eliminated burn at the contact face, so
in theory, the points lasted electrically for ever, with less need for
adjustment. Some simple 'electronic' ignition systems use an ancilliary
pickup winding, positioned such that it produces a pulse at the appropriate
firing time, as the primary magnet whizzes past. This pulse is then used to
drive the primary coil switch, which again may be as simple as a transistor.
Full blown electronic ignition uses a system known as capacitive discharge,
where a high voltage pulse is placed across the primary winding at the
appropriate time. This makes the coil 'ring' for several cycles. As far as I
know, this type of ignition is not employed in magneto systems, due to the
fact that there is usually an inverter to produce the high voltage for the
primary pulse, and this requires an external power source to operate. I
could be wrong there though. I haven't read the whole article and its follow
up on the kart engine magneto systems, but it probably tells you somewhere
in the text, all about electronics as adapted to work with this ignition
scheme.

Arfa

[paulbedd...@hotmail.com]

Thanks again for the help guys.
Now to get that blooming fly wheel off!!
Ta

[Tim Lamb]

In message
<fbf12c9a-bc8a-41c0...@t3g2000yqa.googlegroups.com>,
meow...@care2.com writes

>>
>> Clean the make and break contacts with a bit of fine emery cloth.
>>
>> Then waft warm air around the ignition coil. Don't overcook it:-)
>>
>> regards
>
>Mowers are normally magneto, which is just a magnet on the flywheel
>whizzing past a coil, so no contacts anywhere.

I'm a bit out of date but iron horse engines used to be both. The make
and break operated by a cam lobe to co-incide with the magnet passing
the coil. I thought Briggs and Stratton were similar?

>
>OP is fairly likely to get lucky just by drying it out. 2 or 3 days in
>the shed for a semi-enclosed device is nowhere near enough. Expose it
>and let it sit a week indoors. If thats impractical, put a warm air
>blower on it for a couple of days - be sure not to overheat anything
>though.

Quite!

regards

--
Tim Lamb

[Tim Lamb]

In message
<d5425141-a1d5-4b3a...@v38g2000yqb.googlegroups.com>,
paulbedd...@hotmail.com writes

>Thanks again for the help guys.
>Now to get that blooming fly wheel off!!

Try heat first.

Check the thread direction before getting heavy with it.

I used hub pullers because I have some:-)

regards

--
Tim Lamb

[paulbedd...@hotmail.com]

Thanks again guys
Ok i think the plan might be to persuade the missus to let me bring it
in the house for a few days. Wish me luck on that!!

[Dave Liquorice]

On Wed, 11 Mar 2009 20:52:02 +0000, Tim Lamb wrote:

> Try heat first.

Might not be to good for the magnets...

> Check the thread direction before getting heavy with it.

Aye the nut might be lefthand thread.

> I used hub pullers because I have some:-)

Took mine down to the local garage and their pullers struggled but it did
eventually come off.

--
Cheers
Dave.

[Arfa Daily]

"gazz" <n...@spam.ta> wrote in message
news:71q75fF...@mid.individual.net...

>
> <paulbedd...@hotmail.com> wrote in message
> news:6ce80da0-8b04-408c...@q9g2000yqc.googlegroups.com...
>> Cheers. I'll have a look, however the mower i have has electronic
>> ignition. I thought the electronic ignition relaced the need for
>> points etc?
>
> it does,
>
> the mower engines with points are ancient, villiers and that kind of
> stuff,

Well, I'd have to dispute that. My first petrol mower was a brand new
Qualcast, probably 20 years ago, and that most certainly had a set of points
...

>
> nowadays the spart is generated very simply, magnet set in the fly wheel
> edge, and a coil mounted close to the flywheel, as the magnet spins past
> the coil, it induces a current in the low tension coil, when the magnet
> moves past it, the current is stopped and it fires the spark plug from the
> HT part of the coil, it's a nice simple all in one unit, better known as a
> CDI unit i believe.

Points or fully or partial electronic interuption, it never-the-less is
still there, and has to be get a) a voltage of sufficient amplitude to
produce a spark at the plug and b) to ensure that spark occurs at the
correct time. If the system tried to rely on just the magnet moving past the
coil, the transition from magnetic field present to magnetic field gone,
would not be sharp enough to induce a sufficiently sized voltage in the HT
winding to produce a spark.

Arfa

[Dave Liquorice]

On Thu, 12 Mar 2009 01:51:17 -0000, Arfa Daily wrote:

> Points or fully or partial electronic interuption, it never-the-less is
> still there, and has to be get a) a voltage of sufficient amplitude to
> produce a spark at the plug and b) to ensure that spark occurs at the
> correct time.

Bollocks. My 5 to 10 year old 4 stroke B&S based rotary mower has no
points, neither does my 2 stroke Ryobi strimmer. Both have sealed ignition
units.

> If the system tried to rely on just the magnet moving past the coil,
> the transition from magnetic field present to magnetic field gone, would
> not be sharp enough to induce a sufficiently sized voltage in the HT
> winding to produce a spark.

You're making the assumption that there is only one magnet. IIRC there are
4 quite powerful ones around the edge of the flywheel of my fourstroke.
Not sure how the timing is done but it sure isn't via points and a
cam/push rod.

--
Cheers
Dave.

[Arfa Daily]

"Dave Liquorice" <allsortsn...@howhill.com> wrote in message
news:nyyfbegfubjuvyypb...@srv1.howhill.net...

> On Thu, 12 Mar 2009 01:51:17 -0000, Arfa Daily wrote:
>
>> Points or fully or partial electronic interuption, it never-the-less is
>> still there, and has to be get a) a voltage of sufficient amplitude to
>> produce a spark at the plug and b) to ensure that spark occurs at the
>> correct time.
>
> Bollocks. My 5 to 10 year old 4 stroke B&S based rotary mower has no
> points, neither does my 2 stroke Ryobi strimmer. Both have sealed ignition
> units.
>

- that you can't see inside ...

It is not bollocks, as you so eloquently put it. If you took the time to
actually READ what I've said in any of the posts, or follow up on any of the
links to what others who know more about it than either of us, you would
have actually understood that the interuption scheme does not *have* to be
points, merely that it *can* be. Just because you can't *see* a set of
points, you cannot assume that it all works in the fashion you believe.
*Some* interuption schemes work by having an additional coil to the LT side
of the magneto coil, with the purpose of picking up a narrow pulse at the
appropriate time, to drive the 'switch', which may be a transistor. The
transistor is the equivalent of the points. The pulse is the equivalent of
the mechanical cam to drive them.

>> If the system tried to rely on just the magnet moving past the coil,
>> the transition from magnetic field present to magnetic field gone, would
>> not be sharp enough to induce a sufficiently sized voltage in the HT
>> winding to produce a spark.
>
> You're making the assumption that there is only one magnet. IIRC there are
> 4 quite powerful ones around the edge of the flywheel of my fourstroke.
> Not sure how the timing is done but it sure isn't via points and a
> cam/push rod.
>
> --
> Cheers
> Dave.
>

I am making no such assumption. Two or four magnets. It makes little
difference to the fact that the rise time of the flux in the core of the
magneto coil, will be too slow to produce an HT pulse of sufficient
amplitude to cause a spark at the plug with any accuracy of timing, if at
all. The fact that you say that you don't understand how the timing is done
but that it's not done by points, a cam and a push rod (?) shows that you do
not understand enough about ignition systems, to comment.

Try actually *reading* http://www.foxvalleykart.com:80/timing1.html

to understand about timing in magneto fired systems.

Arfa

[The Natural Philosopher]

I think the issue is whethr or not you have a bettery.

If you hav a battery, then a CD or othr discharge system works well.
Normally hall effect sensors and a magnet do th timing.

CD systms use a 200v HT in a capcatir, that is chargd by an inverter,
and than 'applid' to teh coil primary.

Non CD electronic systems simply short the coil across the battery, and
'open circuit' it at the correct point to give a primary rung voltage
around 200v, and th secondary up around the 15KV nedeed to fire the spark.

On battery less engines, the only way to generate the voltage is via a
magneto. The traditional mechanism was a magnet moving past a coil,
which was held shorted. This formed IIRC the primary of a transformer,
and th contacts then opened, and the collapsing field generated a spark
in the secondary windings. Contactless versions merely have a bit of
electronics probably fed off the primary circuit that replaces the
contacts with something like a switching FET that is coupled to a hall
effect sensor.

On single cylinder 4 stroke its normal to have a wasted spark on the
exhaust cycle, rather than taking the hall effect of the the camshaft.

[Mark]

"The Natural Philosopher" <a@b.c> wrote in message
news:123687010...@proxy00.news.clara.net...

> Arfa Daily wrote:
>> <paulbedd...@hotmail.com> wrote in message
>> news:6ce80da0-8b04-408c...@q9g2000yqc.googlegroups.com...
>>> Cheers. I'll have a look, however the mower i have has electronic
>>> ignition. I thought the electronic ignition relaced the need for
>
>

> Contactless versions merely have a bit of electronics probably fed off the
> primary circuit that replaces the contacts with something like a switching
> FET that is coupled to a hall effect sensor.

Lol
On a piddling lawn mower engine it doesn't have to be that complicated at
all.
Just a simple thirister will suffice
www.roosterignitions.com/docs/rbjnrfitting.pdf

in fact B&S used to do an add-on of the above to replace the points on old
engines.

Often wondered how people could be over qualified for a job, now I know.

-

[Arfa Daily]

"The Natural Philosopher" <a@b.c> wrote in message
news:123687010...@proxy00.news.clara.net...

Yes. All absolutely correct, and exactly what I have been trying to get Dave
to understand. Also, correct on the way CDI systems work, and the fact that
an inverter, powered from an external source (a vehicle battery /
alternator) is used to produce the high voltage to charge the coil coupling
cap. I believe that I said just that in an earlier post.

Arfa

[Arfa Daily]

"Mark" <Ma...@127.0.0.1> wrote in message
news:MKbul.6089$Lc7....@text.news.virginmedia.com...

Well that actually tells us nothing except that Rooster make a black box
with three connections which replaces the points. What exactly leads you to
believe that there is a thyristor in there ? There might be, but nothing on
the cited document actually says so. Even if the switching element is a
thyristor, it's still going to need to be triggered, which means that it is
unlikely that there is *just* a thyristor in there.

Arfa

[Mark]

"Arfa Daily" <arfa....@ntlworld.com> wrote in message
news:0fcul.30095$Yl7....@newsfe30.ams2...

>>>
>>>
>>> Contactless versions merely have a bit of electronics probably fed off
>>> the primary circuit that replaces the contacts with something like a
>>> switching FET that is coupled to a hall effect sensor.
>>
>> Lol
>> On a piddling lawn mower engine it doesn't have to be that complicated at
>> all.
>> Just a simple thirister will suffice
>> www.roosterignitions.com/docs/rbjnrfitting.pdf
>>
>> in fact B&S used to do an add-on of the above to replace the points on
>> old engines.
>>
>> Often wondered how people could be over qualified for a job, now I know.
>>
>>
>>
>
> Well that actually tells us nothing except that Rooster make a black box
> with three connections which replaces the points. What exactly leads you
> to believe that there is a thyristor in there ?

Because I use one (a thyristor) on my own lawn mower and motor bike

>There might be, but nothing on the cited document actually says so. Even if
>the switching element is a thyristor, it's still going to need to be
>triggered, which means that it is unlikely that there is *just* a thyristor
>in there.

You need to do a Lot more reading on how a thyristor works.

-

[The Natural Philosopher]

Mark wrote:
> "The Natural Philosopher" <a@b.c> wrote in message
> news:123687010...@proxy00.news.clara.net...
>> Arfa Daily wrote:
>>> <paulbedd...@hotmail.com> wrote in message
>>> news:6ce80da0-8b04-408c...@q9g2000yqc.googlegroups.com...
>>>> Cheers. I'll have a look, however the mower i have has electronic
>>>> ignition. I thought the electronic ignition relaced the need for
>>
>> Contactless versions merely have a bit of electronics probably fed off the
>> primary circuit that replaces the contacts with something like a switching
>> FET that is coupled to a hall effect sensor.
>
> Lol
> On a piddling lawn mower engine it doesn't have to be that complicated at
> all.
> Just a simple thirister will suffice
> www.roosterignitions.com/docs/rbjnrfitting.pdf
>

And what maks youy think that that is just a 'simple thyristor'

> in fact B&S used to do an add-on of the above to replace the points on old
> engines.
>
> Often wondered how people could be over qualified for a job, now I know.
>
>

Often wondered how people can determine the internals of a three wire
block just by reading an advert.

>
> -
>
>
>
>
>
>

[The Natural Philosopher]

Spent many happy hours doing just that.

>
>
> -
>
>

[Arfa Daily]

"Mark" <Ma...@127.0.0.1> wrote in message

news:E5dul.6123$Lc7....@text.news.virginmedia.com...

I have been working with thyristors for some 35 years, so I have a pretty
good idea how they work ...

So, are you telling me that you have a 'thyristor ignition module' on each
of your engines, or that you have an actual single thyristor on them, that
you have bought from Farnell or wherever, and grafted on yourself in place
of previously existing points ?

Arfa

[The Natural Philosopher]

I think we already know the answer arfa..;-)

[Arfa Daily]

"The Natural Philosopher" <a@b.c> wrote in message

news:123691240...@proxy01.news.clara.net...

That was my thought ...

Arfa

[paulbedd...@hotmail.com]

Update
Right folks.
Here is what i did.
New spark plug. New HT lead cap.
Recoil starter off. Flywheel off. Used a wooden spoon of all things to
prize it off.
Removed magnito. Half an hour on it with wife's hair dryer.
Dried out inside of flywheel. Reassembled and hey presto!!
Started first time!!
Thanks for the help guys

[The Natural Philosopher]

And did it have 'just a thyristor' in it? :-)

[Arfa Daily]

"The Natural Philosopher" <a@b.c> wrote in message

news:123724090...@proxy02.news.clara.net...

d;~}

Arfa

[paulbedd...@hotmail.com]

All it had in it was what looked like a sealed unit, that was non
adjustable.
There were no points to clean or gaps to set etc.
I just dried it all off, put it back together and it worked.

[Arfa Daily]

<paulbedd...@hotmail.com> wrote in message
news:f393ee49-2125-4a76...@j8g2000yql.googlegroups.com...

Yes, I'm sure that's probably true. The comments about the thyristor were
just TNP and me having a bit of a joke with one another at the expense of
some comments made earlier in the thread by another poster who questioned
TNP's (over !) qualification to comment as he did, and my understanding of
how thyristors work ... What you have there is a sealed ignition module,
which carries out the switching function that would, a few years back, have
been done by the points, and which may or may not have a thyristor in it,
but certainly other components as well.

Arfa

[ian.fre...@gmail.com]

Take off the magneto flywheel (the nut loosens clockwise and not anti clockwise).A puller is advisable or leave the nut on such that the first few threads are recessed in the nut. Take a small hammer or better still a copper mallet and while pulling the magneto"flywheel" whack the nut at the centre and the "flywheel should jump free. Take off the nut and slide the "flywheel off the tapered caranckshaft stud.Clean all parts with petrol and allow to dry for several hours. Grease the cam and oil the pad which rubs against the crankshaft. Check the points gap ( 0.020") but first clean the points with water paper to remove high spots.Reassemble and with the spark plug removed, spin the "flywheel" while the HT line to the plug is about 1 mm from an earth point. The plug must be removed or the compression will make "spinning" of the flywheel almost impossible. If there is a spark to earth then the ignition system is probably fine.Try starting your mower now once you have fuelled up and primed the carb with the tickler.

Regards

Ian Freemantle

[Tim+]

After 5 years I'm guessing the OP has sorted the problem. ;-)

Tim

[damdu...@yahoo.co.uk]

On Fri, 20 Feb 2015 17:32:56 +0000, Tim+ <timdow...@yahoo.co.uk>
wrote:

><ian.fre...@gmail.com> wrote:
>> Take off the magneto flywheel (the nut loosens clockwise and not anti
>> clockwise).A puller is advisable or leave the nut on such that the first
>> few threads are recessed in the nut.

>> fine.Try starting your mower now once you have fuelled up and primed the
>> carb with the tickler.
>>
>> Regards
>>
>> Ian Freemantle
>
>After 5 years I'm guessing the OP has sorted the problem. ;-)
>
>Tim

or lives here
http://1.bp.blogspot.com/-KjBrrAgyKtQ/UU-4V0PQZ6I/AAAAAAAABdE/SpMdJ2rH874/s1600/729grass-620x349.jpg

G.Harman

[pe...@peters-eaters.co.uk]

On Tuesday, 10 March 2009 23:19:38 UTC, paulbedd...@hotmail.com wrote:
> thanks for the response.
> Nah, nothing as serious as that.
> engine turns ok and compression is good. There is just no spark at the
> plug.

Ihavethesameproblemwithmyatco14comodorewiththesuffolkengineIcametotheconclusiontheelectronicignitionhadfailedtheflywheelhasalefthandthreadiboughtanewstatorandfitteditstillnospark

[Andy Burns]

pe...@peters-eaters.co.uk wrote:

>Ihavethesameproblemwithmyatco14comodorewiththesuffolkengineIcametotheconclusiontheelectronicignitionhadfailedtheflywheelhasalefthandthreadiboughtanewstatorandfitteditstillnospark

LipSmackingThirstQuenchingAceTastingSuffolkPunch?

[Phil L]

fuckoffanddieyougormlesscunt

[The Other John]

On Thu, 15 Jun 2017 09:44:13 -0700, peter wrote:


>Ihavethesameproblemwithmyatco14comodorewiththesuffolkengineIcametotheconclusiontheelectronicignitionhadfailedtheflywheelhasalefthandthreadiboughtanewstatorandfitteditstillnospark

You've also got a problem with your space bar! and your eyes since you
can't read dates!

--
TOJ.

[Brian Gaff]

Blimey, his spacebarhasstoppedworkingagain

Brian

--
----- -
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...
bri...@blueyonder.co.uk
Blind user, so no pictures please!
<pe...@peters-eaters.co.uk> wrote in message
news:c9a4a1d4-1932-4496...@googlegroups.com...

[grs...@aol.com]

On Tuesday, March 10, 2009 at 11:09:19 PM UTC, paulbedd...@hotmail.com wrote:
> Hi
>
> My first post. Hope this is the correct section to post this question.
>
> I've recently gotten hold of a old suffolk punch petrol lawnmower. Was
> running ok and was looking forward to using in on my lawn.
>
> Pulled it out of the shed at the weekend and thought i'd give it a
> good clean for the season. I decided the best thing to do would be to
> spray the engine, in fact the entire mower, in enginer degreaser,
> leave it running for a while then pressure wash it. On reflection
> probably not the best idea. The old saying goes "if it's not broken,
> dont mend it!"
>
> Not long after i'd started pressure washing, the mower cut out and now
> has about as much life in it as a dodo!! There is just no spark at the
> plug.
>
> I had assumed that water must have gotten into the ignition system and
> hoped that if i left it for a few days it would dry out and everything
> would be fine and dandy. But no! Three days later and still nothing.
>
> Can anyone help? Do you think i have broken anything or do you think
> it is still simply damp and needs more time to dry out? Is there
> anything i can do to try and solve the problem or help dry it out? I
> have read about megneto coil but not sure what this is?
>
> Any help much appreciated!!

[Tim+]

Excellent helpful and timely response! And to think that some folk think
that AOLers are dim. ;-)

Tim

--
Please don't feed the trolls

[Brian Gaff]

Only 2009 this time, we are slowly getting newer posts. I don't have to look
where this came from do I?

Brian

--
----- -
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...
bri...@blueyonder.co.uk
Blind user, so no pictures please!

<grs...@aol.com> wrote in message
news:b566c29b-e1fb-4778...@googlegroups.com...

[newshound]

OTOH it has probably dried out by now.