can any one help,I am a Girl doing up my own boat so im not very good with engines but im learning! i have aquired an old WS 341HH3 silver century 40 seagull. Im trying to replace the old Com8 spark plug and have got a D16. but the end is different, com8 has screw fit that screws into the lead cover, but the new D16 looks like a push on connection with screw threads inside it?? do i adapt the D16 or do i need a different plug altogether, or do i replace the lead with the cover on??
thanks
sarah x
One day I am going to ditch the original Seagull plug cap on my Featherweight, screw a "bullet" from an old plug onto the plug and fit a nice push on rubber plug cap in its place.
The push on ones dont come unscrewed while you are going along!
These are the Plug Caps I use, NGK LZFH, non resistered with a seal at each end which makes them fairly water resistant, takes seconds to fit, they don't loosen themselves once on and the good part is that they only cost £1.00 each
What's wrong with the original ones, its not as though you cannot get them any more, you could put on a modern plug cap and even a modern cdi unit, or just get a modern outboard instead.
If anyone plans on replacing their original plug caps - send 'em my way - I think they're the best design ever - keeps water off the insulator whilst allowing air to cool it. Brilliant.
The COM-8 plugs - another good design - I paid serious money for half a dozen, took 'em apart and cleaned 'em well, and they're now as good as new. Sod modern disposable stuff.
from experience I have found the original plug cap to be a pain, it can come loose and come off, it can also be difficult to replace, getting the screw part of the cap back on the plug especially when you are on the water can be awkward and time consuming too replace, I stopped using caps a long time ago and never have any problems, the push on caps I think are a good alternative
Charles, I've just poped into the garage to have a look and unfortunately No, these NGK caps don't fit the D16 plugs. I tend to use the NGK AB6 (cheap supplier) and they fit fine.
I've also got a later rubber seagull plug cap, the one with the little hose clip, and that doesn't fit the D16 plug either.
Welcome to Seagull ownership. If you're not that familiar with outboards, these engines are a great tutorial. So simple in their operation and all, and plenty of great intel to be found on this web site.
When you get a chance, please show us the boat you're working with. It's always nice to see how the Seagulls are put to use.
Best regards,
Ted
There is nothing so useless as doing efficiently that which should not be done at all.
- Prof. Peter Drucker
i have aquired an old WS 341HH3 silver century 40 seagull. Im trying to replace the old Com8 spark plug and have got a D16. but the end is different, com8 has screw fit that screws into the lead cover, but the new D16 looks like a push on connection with screw threads inside it?? do i adapt the D16 or do i need a different plug altogether, or do i replace the lead with the cover on?? 
