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digger
23rd August 2012, 07:38 PM
In efforts to breathe life into a non functioning motor, I had to 'rebuild' the dizzy cap and leads, using a series of different old dizzy caps and leads to fix
up the dizzy cap

During this exercise I noticed something unusual... whilst putting all the leads, caps etc in together I have noticed the spark plug "shrouds" (bakelite) are of three different designs..

see attached photo,
https://www.aulro.com/afvb/images/imported/2012/08/475.jpgno
hole in side
one hole in side
two holes in side..

what reason would there be for these differences??
(eg what year/model for what design?)-

I look forward to hearing /reading replies!

Ta
Digger

russellrovers
23rd August 2012, 07:51 PM
In efforts to breathe life into a non functioning motor, I had to 'rebuild' the dizzy cap and leads, using a series of different old dizzy caps and leads to fix
up the dizzy cap

During this exercise I noticed something unusual... whilst putting all the leads, caps etc in together I have noticed the spark plug "shrouds" (bakelite) are of three different designs..

see attached photo,
https://www.aulro.com/afvb/images/imported/2012/08/475.jpgno
hole in side
one hole in side
two holes in side..

what reason would there be for these differences??
(eg what year/model for what design?)-

I look forward to hearing /reading replies!

Ta
Digger
hi digger he 2 long ones are suppresors jim

digger
23rd August 2012, 09:29 PM
hi digger he 2 long ones are suppresors jim


As in for radio signal??

wrinklearthur
23rd August 2012, 10:00 PM
As in for radio signal??

Helps radio frequency interference a bit and can give a more intense but shorter timed spark.
.

russellrovers
24th August 2012, 04:43 AM
hi digger he 2 long ones are suppresors jim
a very nice extra i will look in my lucas electric box and see if i can help you jim

JDNSW
24th August 2012, 05:39 AM
As in for radio signal??

When the Series 1 came out in 1948, few would have even thought of using a radio in one, or indeed any other car. (In Australia, as an example, few cars had factory fitted radios until the 1960s) As radios in cars became more common, and as ignition interference to television became more noticeable (remember no TV in Australia until 1956, almost the end of Series 1!) it became common to do something about it.

The initial method of doing this was to fit a resistor in series with each plug lead, the resistor being in a moulded bakelite or plastic housing. This could be screwed to the plug connector as here, or part way along the lead. This was eventually superseded by the now universal practice of having resistive leads. It is most important not to use both. If you do, it is likely that there will be zero interference - because the engine will not start. At best you can expect a fussy engine that will only run with everything set exactly right.

You can expect problems finding non-resistive (metallic wire) high tension leads, but should be able to find them. (otherwise, don't use the the discrete resistors) If using resistive leads on these bakelite plug shrouds (and the screw connectors on the distributor) you need to take care that the termination makes good contact - they are designed for wire.

John

wrinklearthur
24th August 2012, 06:48 AM
During this exercise I noticed something unusual... whilst putting all the leads, caps etc in together I have noticed the spark plug "shrouds" (bakelite) are of three different designs..

see attached photo,
https://www.aulro.com/afvb/images/imported/2012/08/475.jpg
what reason would there be for these differences??
(eg what year/model for what design?)

What I remember about these plug shrouds is, the middle one is a Land rover type and the two either side are from Rover P3 car engines.

https://www.aulro.com/afvb/images/imported/2012/08/476.jpg

https://www.aulro.com/afvb/
1953 80"

digger
24th August 2012, 02:30 PM
http://imgc.classistatic.com/cps/blnc/120822/990r1/1681mi0_20.jpeg
1953 80"

is that a bucket bolted to the firewall?? :Dl

wrinklearthur
24th August 2012, 08:47 PM
is that a bucket bolted to the firewall?? :Dl

Hush, we are in the presence of a higher authority here.
Upon the lifting the bonnet into the form of a stele, one must anoint their self from a stoup ( your bucket ).
Then proceed into the sacred inner workings of Land Rover.
.

862993
27th August 2012, 11:48 AM
hi digger he 2 long ones are suppresors jim

Hi Digger,

The caps on the left and right have suppressors, these are screwed ontop of the caps, nothing to do with the caps themselves and you can remove them if no radio fitted.

The early caps had no holes. These had issues with condensation on the inside of the sealed cap so they changed to one small hole on each side then to two to allow for evaporation.

Id be happy to take the early ones off your hands as they really are useless :angel:

Cheers