HSD12704.L

[Oyster 49]

I just picked up this engine, a real find Seems to be an original HSD, with long shaft, early bargepusher gearbox and 3 blade prop which has a broken blade Also the remains of a skeletal mount. A very rare old seagull for sure, in fact one of the rarest. Really pleased to have it.

[Collector Inspector]

What a ripper.

What cunning plan re the prop?

BnC

[Nudge]

What cunning plan re the prop?

It could be sent to me and I can cast a new one.

I can use the old one as a pattern to make a new one even if one blade is missing.

[Oyster 49]

Hi Nudge, I was thinking about asking you about this

Let me look around first to see what can be found, I think I know where one is, but I need two, as I’ve now got two HSD engines.

If we are going to cast some it might be worth doing a few more? Four blade bargepushers are often available, but not 3 blade ones!

[Oyster 49]

Has anybody else got a HSD engine?
In the SD register I recall there being only one, but now there are 3. I’m sure there are more hiding out there.

On the subject of the SD register, is it still available to view? Must badger Hugz about it.

[Oyster 49]

Here are the testing data docs for the HSD engine, from the experimental bridging establishment, dated November 1945. It shows a two blade prop! I got this copy from a search of the national archives. It seems the army did not take this option, but seagull continued with it and eventually sold AHC engines in numbers.

[Nudge]

Happy to give it a go. Let me know if you want to give it a try.

[Horsley-Anarak]

I would get a new blade tig welded back on, but casting a new one would be a great project.
3d print and lost plastic casting.

[Oyster 49]

Yes, I hope I know where a 3 blade prop is some interesting ideas about making a new one for sure.

[Oyster 49]

Finally got around to stripping this engine. I've decided to do no cosmetic work apart from a general clean, light buff up of the alloy parts, and then put it back together. Nothing will be painted, and it looks like the coil is toast. It was partially seized, which turns out to be the piston tight in the bore, so I will remove the cylinder and give the bore a light hone.
The gearbox came off real easy apart from one bolt shearing, despite heating both first. So some very careful drilling next. The gearbox is lovely and smooth, so I will clean it out, soak it with parafinn and leave it as-is.

I'm still looking for a 3 bladed prop if anybody happens to have one? Cash, swap, anything considered!

[Horsley-Anarak]

Weld a thick washer on the broken bolt, then weld a nut to the washer, that will get it out.

[Oyster 49]

Yes, but I’ve not got any welding kit

[Oyster 49]

So a bit more work done, magneto dismantled, all parts cleaned, and power head stripped. Next job is to flush out the rust flakes from the water jacket, and order a new coil from Villiers parts. Quite a quick strip and build as it’s all in such good condition Even stripping the magneto backplate was fairly straightforward.
No painting to be done, just a general clean and leave as-is, in original condition. I’m even using the original fasteners.

[Collector Inspector]

Very

BnC

[beerjam]

PM/email sent

Cheers, Mark