Hints and Tips - HT Lead Suppressors

From: Peter Adams
Sent: 20 August 1999
To: british-cars-pre-war
Subject: HT Lead Suppressors

My recently acquired 1937 Rolls-Royce 25/30 has red, right-angled, plastic suppressors marked NGK connecting the HT leads to the sparking plugs, and I would like to remove this horrible anachronism.

A photograph in the handbook shows the HT leads were originally fitted with flat brass connectors, but before I fit something similar, can anyone tell me what the UK regulations require in respect of suppressors for a car made in 1937?

--
Peter Adams,
Lincolnshire, England


From: David Cochrane
Sent: 20 August 1999
To: peter@brig.demon.co.uk
CC: british-cars-pre-war
Subject: Re: HT Lead Suppressors

> A photograph in the handbook shows the HT leads were originally fitted
> with flat brass connectors, but before I fit something similar, can
> anyone tell me what the UK regulations require in respect of suppressors
> for a car made in 1937?

Nothing at all. You can still get the flat brass connectors. Your CB radio won't work so well though.

Regards, David Cochrane

Rugby, England


From: John Hardy
Sent: 21 August 1999
To: David Cochrane
CC: british-cars-pre-war
Subject: Re: HT Lead Suppressors

It's also a point to remember that if you've got magneto ignition; mags don't like suppressed leads or caps. Don't know if the 25/30 had a mag or not but I thought that some of these engines had dual ignition

JH


From: Peter Adams
Sent: 21 August 1999
To: british-cars-pre-war
Subject: Re: HT Lead Suppressors

John Hardy writes
>It's also a point to rember that if you've got magneto ignition; mags don't
>like suppressed leads or caps. Don't know if the 25/30 had a mag or not but
>I thought that some of these engines had dual ignition
>
>JH

You are not far wrong - the previous model 20/25 had dual magneto and coil ignition - as did the 20HP before it. The 25/30 was the first model to have twin coils instead.

It was also the first model to have radiator shutters controlled by a thermostat. The previous manual control was pretty well eternal and indestructible, but, of course, my automatic system does not work.

I am grateful to everyone who assured me that there are no regulations pertaining to HT suppressors. I thought there might be something similar to the regulations that specify: Regardless of age, all vehicles must have two rear lights - and windscreen washers, if the screen does not open.

I shall action this day - those NGK suppressors are history.

Peter
--
Peter Adams,
Lincolnshire, England


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