Saving Old Seagulls

I'm restoring a early 60s century
The original head has a cracked tank mount that's been fixed with some screws and sheet aluminum
It'sa clever fix but a bit wobbly
I was wondering if it's possible to weld it
Is it aluminum or is it that special Seagull alloy ?

Dont see why not, Iv had an aluminum Seagull bracket welded that was broken. Just need to find a good aluminum welder. I found a local engineering firm to do it, cant remember the price but it wasnt a lot.

HTS2000 aluminium brazing rods really do work very well. A MAPP gas or propane torch is all you need. I've used them to fill holes and to rejoin a broken propellor tip.

I've welded several with no problems, some distort, but a clout with a wooden block on a very flat surface will cure that.

Clamp both tank supports to a steel plate before welding to ensure they finish parallel & the holes are the correct distance apart & the area to be welded must be squeaky clean!

I agree about HTS2000, it's a good product.

For anything cosmetic it's worth noting that HTS2000 isn't the same colour as a gearbox or a prop.

I've found that the alloy in the transm bracket, if the same, TIG welds fine with filler wire for aluminium extrusions.
There is a low temp aluminium product here that can be used to weld up holes in aluminium beer cans with a bic lighter. I don't know if this HTS2000 is similar or not. It acts more like a solder and although it looks like a good weld and looks like aluminium, over time the welds usually fail as its not a proper homogenous bond. Easy for the handyman though.
It would be interesting to know if anyone has done test plates to test the welds.

why go through all the trouble of getting it welded when you can buy a cylinder head of ebay for less than £10

Ht 2000 is nice to use but requires a LOT of heat, but is not suitable where it comes in contact with salt water due to it's zinc content, it's much harder than aluminium when machining, so holes that are drilled down the "weld" join will wander badly.

Look at the 102 pics that Jerseyman just posted, the carb that contained zinc has dissolved but the gearbox doesn't look too bad, a perfect example of why I only use zinc based alloys for sacraficial anodes.

supersaint61 wrote:why go through all the trouble of getting it welded when you can buy a cylinder head of ebay for less than £10

Brilliant question and one which I can answer as when your as anal as me it sometimes pains me to see waste.
I like to fix the unfixable regardless of cost just because I can or for the engineering challenge.

I do have another head but it''s a little corroded.
My brother is a tig welding god, welding up his own circus gear all the time
He just taught me a bit recently too
Maybe I'll take it over there and give it a whirr
I too would rather fix something than just buy a new one
That's why I have Seagulls
Thanks a lot

TIG or MIG is the way to go. A MIG was used on my broken bracket. Also iv had coroded water galeries on aluminum car cylinder heads MIG welded then refaced.

Here's the head I have to potentially replace my broken one if I don't weld it
It's corroded where the water jacket channels would be (which to me is strange cause my new head gasket doesn't have the channels cut.) There's definitely some pitting in those areas
Too corroded or should I weld the other?

Looks ok to me. Mine are in similar condition. For me the important part is that the cylinder seals nicely. I use a sear of Hylomar on the spigot and Loctite silicone on the rest. Remember there's no high pressure in the water compartment so all your really trying to do is stop water weeping around the edges.
I also hold a flat file flat on the gasket surface and push around to clean up any high spots, corrosion and burrs.

That looks like electrolytic corrosion caused by the close proximity of copper & aluminium in the presence of an electrolyte (fresh or salt water).

It would be nice if you could skim the head but failing that, remove all the crud & apply a liberal smear of silicon RTV high temperature sealent to fill all the voids to prevent water filling the space, also treat the cylinder face of the gasket with a light smear of RTV & torque the head down to 18 ft lbs.