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McDonald SD.


Hi all. Picked up a McDonald SD on Sunday. Turns over with great compression (more than my running SE), but has several broken parts. Most of these I have the bits to braze back together, but not the injector lever; the broken-off piece is missing. I can see it has had a number of repairs in antiquity (thinking it was dropped) and it has been dropped again more recently.
Does anyone have one which they could take a picture of the lever for me, please? I figure it's just flat, but would like to be sure.

Thanks, Jarrod.


I also found a faint trace of red pinstriping. Doubt I'll ever get to painting it, but it would be nice to redo that, if I did. My SE has only grey paint. This one seems to have grey underneath the green. Does anyone know what's original for these?
Thanks, Resized_20200628_184206.jpegJarrod.


Scotty 2

Hello Jarrod.
Nice little McDonald those SD's. A lot smaller then the C series which makes them easier to move around. 2hp @ 500rpm. 3-1/2x5" stroke. Yours would have a cylinder liner in it as well.
Yep, It's fairly flat in the front but, if I remember, there's a bit of a rib on the back for strength. It also kinda curves around the head. If no-one has posted a picture before tonight I'll get a Polaroid of our CC setup. It looks very similar.

As a side note: 726SD is from 1935 (532-744). Good year that year. My mum was born then. Her birthday is tomorrow actually.

Cheers Scott


Obviously it is nothing like the ones on the SE models. I have a spare one of them that has slight damage where the fork should be but it is nothing like what you need.
Happy Birthday to your Mum Scotty for tomorrow..