Saving Old Seagulls

Several months ago on its 48th birthday I decided to give my 40 featherweight a new ngk plug its Champion 8 com having served it well from new in 1967.
I immediately noticed that instead of second pull start it went onto third or fourth.
Replacing the old 8com and it immediately went back to second pull.
Both spark perfectly the only difference being that the 8com has a horizontal spark whereas the ngk has a conventional vertical?
Any thoughts out there other than upgrading the magneto?

I have always used original new old stock spark plugs, rather than the new modern ones, I have had more problems with new spark plus than the original old style ones.
The old two electrode com or three electrode Lodge plugs always seem to work better, in my opinion anyway.

I'd second that.
Strange but true. The older 8com plugs i like to use in my 102's have always done a sterling job. (and you can take them apart to clean them)

The D16 is not a bad plug as an alternative.
I'd double check the points gap first before blaming the spark plug! (often the simplest things)

jon

I to find better results with the 8 com plugs i have but there imposable to get.
Someone here was playing with modified D16 plugs, did that every come to anything, or is it top secret and why you always win.

The Green spark plug company does list them but currently out of stock.
After having posted this I remembered that the century plus circa 1970s hardly used that I have has one.
I also managed to source a pair on e bay for £12 each delivered.
As for price I havnt bought a set of car spark plugs in years but servicing a set of diesel injectors for my mercedes om636 will not leave a lot of change from £400.Never mind modern injectors which are well over £100 each!
So £12 in 48 years for a plug for an engine which I first started up in 1967 when I was a teenager is not bad

I sourced a pair of of new old stock 8coms and whilst it worked out at £12 a plug it was well worth it.First pull from cold as it says in my owners handbook.

Its always a good idea to keep old plugs, I prefer the old two piece plugs especially the harder to come by plugs, as I have always played with engines I have gathered together a little collection, mainly 18mm, but have some 22mm and some 14mm's, like the J8J plugs used in the American motors.
They can be quite collectible, I have the white and normal pink Lodge plugs, lots of unused Champion COM plugs, all two piece type, a handful of mica type KLG plugs and just one Lissen MC1 so far.

Older plugs tend to be better.

Especially the side-throw spark versions as previously mentioned.

If an old plug works with easy starting and no other issue I would use and maintain same.

A modern plug as a "get Back to Dock" yes.

Having a veteran plug extra as a spare makes no sense of course. It will get wet and be ignored in the tool bag/bilge.

An old Gull is not really hard on a plug at all so learn about them, collect the adverts of variations and scour Ebay for bargain examples.

I have found that I now collect..............."Spark Plugs" and all of the related stuff.

SIGH!

B

PS: NGK = NO!

Spark plugs are needed as far as outboards and other motors go, so it's not an unrelated area to collect, The other week I came across a 1955 second edition Lodge spark plug book, I was amazed looking at the marine outboard section, the amount of outboard motors listed that I have never even seen let alone heard of.

hi i also replaced the 8 coms to ngk on my both century plus engines, although i have not noticed any difference i am glad i kept the champion
plugs.
my thoughts now are to refit the champions and use the ngk for emergencey. just does not feel right with modern parts on a vintage engine.

I think it was Henry Ford that once said "If it aint broke, don't fix it"

As Bruce has pointed out, these earlier side throw plugs really are very good for what they are.
A modern replacement is just that......modern!
Not all bad though, D16 still a good plug to use as an alternative.

NGK , never really been a fan of them

jon

To be honest, I use mainly NGK with the odd D16 and 8 COM, I can honestly say I cannot notice any difference in their performance, I tend to fit a new plug on initial inspection and in all the years cannot remember having to replace one after that, if ever I lose the spark, it's normally just the points needing a clean.

Just my bit,
Rene

I think if it a Villiers ignition the motor seems to run better with the original design plug, as far as Wipac and CDI ignitions I have never run one.