Saving Old Seagulls

i have a cylinder head were it appears that the first few plug threads had been buggered so they were filed out. now you can thread a plug in, but there are not enough threads left to hold it secure.

my thought was to drill the hole out, and turn a cylinder on the lathe that would be a snug fit then press it in. next weld or braze it in place. it could then be threaded to accept the spark plug.

i've used the aluminum brazing rods with good results on material that i knew to have aluminum as its major "ingredient".
i reckon that the seagull head is mostly AL but just figured i'd ask if anyone knew for sure before i got too excited.

i have a tig machine but its dc only so not suitable for AL, but if that mode was preferred i'd take it to a local shop.

anyone been down this road before?

What about a helicoil.

http://www.lasaero.com/site/products/ar ... =T00RDRDP1

After looking at those, it's got to be cheaper to buy a good used head, there are loads over here you should be able to get & ship one for circa $20.

What is it a 40 or a century?, I'm sure I have one around here. You can have it for the shipping, if you want. PM me if interested.

Most of the Seagull heads I see here appear to have been helicoiled at some point. On the 40 series [64cc] as well as the Century series [102cc]

this is off a century...
i wish a helicoil would work. when they removed the bad threads they apparently ground them out and enlarged the hole causing the plug to set deeper. on the top there are only 2 theads left. as a result theres not enough "meat" to sink the coil into.

i might try this just as an experiment. i have a lathe here in the basement. the plan would be to turn a cylinder that has internal threads to accept the sparkplug. then drill the head, press the cylinder in and weld it in place. shouldn't take too long or be too much hassle.

but first i'll make an offering to the patron saint of lost causes...can't hurt

phil wrote:Most of the Seagull heads I see here appear to have been helicoiled at some point. On the 40 series [64cc] as well as the Century series [102cc]

The were factory fitted sometime after mid 60's . This was a thread sometime back with my good chum Charles in Poole. Trouble is that Frank can't remember when they started to fit as standard in the factory.

Peter