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How do I fit an old-style spark plug connector on Suffolk Punch?

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MM

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Mar 9, 2017, 4:12:36 AM3/9/17
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The existing connector is broken. I can get a new one from e.g. eBay,
for example:
http://www.ebay.co.uk/itm/Suppressor-Spark-Plug-Cap-Cover-Fits-Suffolk-Qualcast-Lawnmower-/311778038361

This type has a screwed thread inside and presumably I just trim the
end of the coil lead, then screw in the new connector?

Anything I should be aware of when doing this?

Thanks.

MM

T i m

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Mar 9, 2017, 4:35:43 AM3/9/17
to
Only possibly to only trim the minimum if the existing lead is short
as the leads are often part of the coil and so can be lengthened
without a joining piece.

I'm assuming you want to go with this old skool cap because of how you
kill the engine (metal flap that shorts directly to the plug top)?

Cheers, T i m

MM

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Mar 9, 2017, 5:04:35 AM3/9/17
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Thanks. Yes, I did wonder about the length of the lead and whether the
lead can be extended with some kind of connector piece and some spare
cable lead. I think there is actually ample cable lead anyway as the
lead is quite "floppy", going towards the plug.

Re the shorting flap, this machine doesn't have one. To stop the mower
I just push the control on the handle all the way down. I am not
particularly bothered about the type of plug connector, except to say
that this "old skool" type is simple and straightforward, whereas the
rubber boot caps seem to have to be crimped on, and several YouTube
vids I've watched don't make it look easy. Certainly not as easy as
just screwing the old style into the lead.

Also, this old connector type does have a suppressor, so I don't know
what I'd be gaining by using the modern type.

MM

Dave Plowman (News)

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Mar 9, 2017, 5:59:40 AM3/9/17
to
In article <4s62cct4i1ps6u5d1...@4ax.com>,
That ancient type is only suitable for stranded copper core spark plug
leads. Most these days will be a conductive plastic core - which has some
resistance and designed to cut down the RFI from the spark.

With that type, you bare the core and fold it over the outer insulation,
and crimp on the terminal.

--
*In "Casablanca", Humphrey Bogart never said "Play it again, Sam" *

Dave Plowman da...@davenoise.co.uk London SW
To e-mail, change noise into sound.

Broadback

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Mar 9, 2017, 6:00:13 AM3/9/17
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When I saw the headline "Suffolk Punch" I was tempted to reply "Stick it
up its *ss", but refrained! ;-)

MM

unread,
Mar 9, 2017, 7:13:27 AM3/9/17
to
On Thu, 09 Mar 2017 10:58:54 +0000 (GMT), "Dave Plowman (News)"
<da...@davenoise.co.uk> wrote:

>In article <4s62cct4i1ps6u5d1...@4ax.com>,
> MM <kyli...@yahoo.co.uk> wrote:
>> The existing connector is broken. I can get a new one from e.g. eBay,
>> for example:
>> http://www.ebay.co.uk/itm/Suppressor-Spark-Plug-Cap-Cover-Fits-Suffolk-Qualcast-Lawnmower-/311778038361
>
>> This type has a screwed thread inside and presumably I just trim the
>> end of the coil lead, then screw in the new connector?
>
>> Anything I should be aware of when doing this?
>
>> Thanks.
>
>That ancient type is only suitable for stranded copper core spark plug
>leads. Most these days will be a conductive plastic core - which has some
>resistance and designed to cut down the RFI from the spark.

The machine is probably 30 years old at least, so I doubt it's fitted
with all mod cons. Besides the connector in the link above *does* have
a suppressor.

MM

GB

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Mar 9, 2017, 7:33:57 AM3/9/17
to

> Anything I should be aware of when doing this?

Best to test it before use. Attach it to the HT lead. Hold it in your
hand. Spin the engine.



Graeme

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Mar 9, 2017, 8:11:52 AM3/9/17
to
In message <4s62cct4i1ps6u5d1...@4ax.com>, MM
<kyli...@yahoo.co.uk> writes
>
>This type has a screwed thread inside and presumably I just trim the
>end of the coil lead, then screw in the new connector?

May be worth searching for, say, Morris Minor HT leads or similar, if
you prefer the older type. Possibly one for a vintage motorcycle.
Matchless or AJS or similar.
--
Graeme

Dave Plowman (News)

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Mar 9, 2017, 8:51:40 AM3/9/17
to
In article <9ih2cc1bkulrq6882...@4ax.com>,
Ah - right. You can still buy the old copper cored spark plug cable from
the likes of Vehicle Wiring Products.

However, resistive cored cable has been around for more than 30 years.
Although originally impregnated string.

--
*Time is the best teacher; unfortunately it kills all its students.

MM

unread,
Mar 9, 2017, 11:37:58 AM3/9/17
to
On Thu, 09 Mar 2017 10:04:31 +0000, MM <kyli...@yahoo.co.uk> wrote:

>On Thu, 09 Mar 2017 09:35:43 +0000, T i m <ne...@spaced.me.uk> wrote:
>
>Re the shorting flap, this machine doesn't have one.

Since typing that earlier I have read elsewhere that these mowers not
fitted with the shorting tag were shorted in order to stop them by
pushing the throttle lever all the way down, and this action caused
the short and the engine stopped. Maybe my problem is with the
throttle cable, namely that it is not "un-shorting" the coil when I
open the throttle. I just tried again with the spark plug out and the
throttle lever opened fully, but there is still no spark.

I also tried another suggestion, namely to straighten a wire
paperclip, wrap one end round the spark plug terminal and push the
other, straight end into the end of the HT lead. Still no spark.

It looks like I'm going to have to remove the flywheel and check the
points. Perhaps the coil has got damp after 5 months in the garage.

MM

T i m

unread,
Mar 9, 2017, 1:38:27 PM3/9/17
to
On Thu, 09 Mar 2017 10:04:31 +0000, MM <kyli...@yahoo.co.uk> wrote:

<snip>

>>I'm assuming you want to go with this old skool cap because of how you
>>kill the engine (metal flap that shorts directly to the plug top)?
>>
>
>Thanks. Yes, I did wonder about the length of the lead and whether the
>lead can be extended with some kind of connector piece and some spare
>cable lead. I think there is actually ample cable lead anyway as the
>lead is quite "floppy", going towards the plug.

Gdgd.
>
>Re the shorting flap, this machine doesn't have one. To stop the mower
>I just push the control on the handle all the way down. I am not
>particularly bothered about the type of plug connector, except to say
>that this "old skool" type is simple and straightforward, whereas the
>rubber boot caps seem to have to be crimped on, and several YouTube
>vids I've watched don't make it look easy. Certainly not as easy as
>just screwing the old style into the lead.

Personally and to save having an armful of accidental HT, I'd just go
for one of the twist on plastic caps in any case. Or you can get the
metal shielded ones (also screw on) if you want something a bit
tougher / quieter (depending of anyone is listening to the radio
nearby). ;-)
>
>Also, this old connector type does have a suppressor, so I don't know
>what I'd be gaining by using the modern type.

As above ... you only need to touch it once when it's running to
appreciate why enclosed caps are better (if you don't have the
shorting-plate thing). ;-)

Cheers, T i m


tabb...@gmail.com

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Mar 9, 2017, 9:08:18 PM3/9/17
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Ah, I thought you meant a pre-war mower which just had a metal ring on the end of the lead, no plastic AFAICR.

If you need spark leads, old aerial wire without the outer copper works fine.


NT

The Natural Philosopher

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Mar 10, 2017, 3:40:10 AM3/10/17
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http://www.gsparkplug.com/8mm-ht-ignition-lead-cable-high-resistance-hypalon-black.html


--
Religion is regarded by the common people as true, by the wise as
foolish, and by the rulers as useful.

(Seneca the Younger, 65 AD)

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