Seagull Outboard

[Derek Nixon]

I just acquired a 2.5/3.0 HP August 1992 Seagull FP8433H2. and decided to remove the spark plug to check the spark. The plug was tight to unscrew and when it came out a Helicoil came with it. Can anyone advise me on what size Helicoil I need to replace it? The plug that came out seems to be screwed into an adaptor.

 

[Poignard]

I can't answer but if no-one else here can you could try Saving Old Seagulls website for advice:

Saving Old Seagulls: Free British Seagull information, Engine serial number identifier,advice, forum and spare parts.

 

[earlybird]

IIRC, Seagulls originally were fitted an 18mm spark plug. Could be that an adapter has been fitted to use a more commonly available 14mm plug. The measurements refer to the thread diameter.

 

[JumbleDuck]

IIRC, Seagulls originally were fitted an 18mm spark plug. Could be that an adapter has been fitted to use a more commonly available 14mm plug. The measurements refer to the thread diameter.

Somewhere I have a dismantle-able Seagull sparking plug: you can use a small box socket (14mm?) to remove just the insulator and central electrode or a large one (18mm?) to remove the whole thing.

 

[AntarcticPilot]

Certainly the helicoil isn't a normal thing on a Seagull. I suspect a bodge to allow the wrong plug to be fitted; I hope the existing thread hasn't been damaged, or you may need a new cylinder head. Another vote for Saving Old Seagulls.