Saving Old Seagulls

WSPC ENGINE. big smiley face style crack in the side of the cylinder. the Waterjacket was chock full of rust but the bore looks ok. Drilled out the worst of the rust and gave it a scrape out. But my question is, should i bother putting a new head gasket on and run it as is with the crack or replace the cylinder?

Will a 102 AC cylinder fit on my wspc. Apart from the obvious fuel tank bracket difference?

Sadly this it too common on these silver seagull blocks.
I had the same problem on a EFNR and have done what you wan to do and converted it to a 102FNR 102 block, tank, tank mounts, external water pipe, exhaust.
Its a Bitsa but looks good but i cant get it to run, need to clean the carb.

Jacob

Its already got the wrong carb niked from a minimoto, fuel tap from a honda cg125 And a throttle from a lawn mower. So a 102 cylinder will match quite nicely with this bitsa.

Yes, a 102 block will fit your wspc crankcases.
The only thing to be wary of is the shape of the transfer port. The shape and physical size of the transfer port varies quite a bit between older and newer blocks so try and get a block that best matches your crankcases. Should be easy enough to see what i'm talking about.

And then of course make sure the 102 waterjacket isn't as bad as your wspc block was in the first place or you'll be doing this job all over again.


Jon

Got a 102 cylinder cheap enough of ebay. Just waiting for the post man. Will post some pictures of my bitsa when i get it all back together

Which carb are you running on this "bitsa"? (water cooled or air cooled mini moto? i used to run a B1 rep quite heavily modded )

Jon

It came off a watercooled 70cc. That had a siezed piston. It looks quite a small carb but its right for 25/1 fuel mix. The other option is a dt125 carb i hav in the shed.

Your motor was fitted with an Amal 46N (15mm) carb by British Seagull, what size is your replacement?

Where's the crack in your cylinder, a picture would show if it's repairable.

The crack is on the opposite side to the carb. Where it has the writing And its a big smiley face from the base gasket to the head gasket ive decided its scrap. Ive got a 102 block to put on it when i hav a minuite. And im gona shorten it down abit more. Was a long shaft and ive cut it down to the same height as my century 100 but its still a little long for my transom. Another 100mm will make it better.

Right, got it now.
Ching chong copy of a dellorto, (from memory) 19mm id bore where the carb fits onto the stub, a bit smaller at the filter side. As you see it in this way you might find it difficult to start, although as it's a bitsa it's fueling requirements aren't going to be quite as essential as some. It might be a laugh to see if it actually will run like this, but as Charles has said you might be better off with a 46n or better still a later type 416 series carb right off the bat. At least then you know it shouldn't cause any problems, but with a mongrel carb like this and a length of hose connecting the two together might be asking a bit too much from it. You never know though, you might start a new trend with bitsa's. I like it anyway

Jon

Try a bit of RTV over the leak in the water jacket to make it hold water, you've got nothing to loose.

It ran great. Started great with this carb. Had loads of water coming through at the start then 10mins in to the trip the water stopped flowing and alot of steam came out instead. It was like a kettle with the switch stuck on. Stopped and let it cool. Started up first pull perfect for another 10mins same again. So i guess it’s probably down to the head gasket and the cracked waterjacket. Oh and the spark plugs been helicoiled. So not worth sticking a new head gasket on a bad head and cylinder. So a good 102 is the cure
One question for the experienced out there, the water outlet pipe from the cylinder, just let it dribble like a century or pipe into exhaust like 102

Tried cemi metal (belzona) but i think its the head gasket thats the problem