Any idea what this is?

Hi everyone. I am absolutely new to model engines, so couldn't tell you anything about what I am looking at. I am replacing the kitchen in the house and as i was tearing out the old units I found something interesting hiding behind it all...

As far as I can tell, none of the parts have ever been out of the plastic wrap, although air has been getting in and there is rust present on some parts. There is a red sticker on the back of the box which says "Stuart Sun Engine Machined, Made in England"
Is it of any value, or will i start tearing the parts out, cleaning them and putting it together? I'm a marine engineer so i have some degree of confidence in putting this together, although instructions or a helping hand would be much appreciated!

Its a Seuart Turner Sun Engine (castings), bit of a find as they no longer sell this line.

thank you :D What do you mean by castings? I notice on the Stuart website there is "castings" (unmachined) and machined kits.. whats the difference? Is this worth much? I'm itching to break into it but If its of any value Id rather someone who genuinely wants this would have the honor.

The Sun was one of their range of high speed enclosed marine engines intended for use in a boat most likely powered by a flash steam boiler. They could also be used to run a dynamo or small pump. Bit of the history of these engines here

The machined kit which you have would have cost 3-4 times that of the raw casting set so if they made it today you would be looking in the region of £1000. If you do sell it you will get more with the packaging intact

J

Edited By JasonB on 23/04/2018 18:40:08

Some previous owner of the house hiding away purchases from the boss?

It won't be just a matter of putting it together - the raw castings will have to be machined to the correct dimensions. If there's no drawing set with the castings, any purchaser will need to find one, or work out suitable dimensions themselves - possible, potentially with difficulty.

Edited By Mick B1 on 23/04/2018 19:13:38

It's the set of MACHINED castings so just assembly and a bit of fettling required. The Sun was available in 3 formats - castings, machined and assembled.

Interesting read JasonB, thank you. So, is my set machined or cast? The set I have looks to be machined and ready to go together, but I'm no expert! I'll take it to the local model engine guru on Friday as he's away just now and I'll let him have a proper look but I won't be opening up the packaging! Most likely Ian... Its the only explanation I can come up with!
I'll post an album with some close up photos. There is rust present on parts but none of it is terminal as far as I can see. I've certainly repaired worse (On much, much larger engines mind you)
No paperwork Mick, everything is in the photo.

Definately the machined set of parts, you can see the holes in things like the end covers both reamed for the crank and the smaller ones on a PCD to fix them to the crankcase, crank is also machined.

Do the pieces look finished machined; i.e. crankshaft journals finished to size, do the cylinder bores look as though they're finish bored etc. etc. as a marine engineer you should be able to tell when a piece has been finish machined or otherwise. Looking at the pic it seems as though the cylinder covers, crankcase & base need further work, have the pistons been machined, if not then it is a set of castings to be machined up otherwise it is a 'kit' that can be assembled ready to run. Looking at the packaging I would suspect it's a set of castings.

George.

Found you a set of drawings here and looks like I was about right with the machined kit being 3-4 times the cost though a bit cheaper than the £1000 it would cost today if still made

It is machined, I can absolutely confirm that. Pics to follow. its difficult for me to tell because the plastic is quite dirty and my experience with these engines is zilch! I thought It was machined until people here said otherwise and you're right about the crank. At least, I'm used with crankshafts having a bit more.. weight to them! haha. Uploading pics to an imgur album, will share the link.

This is what the crank would be like if you had the raw casting set

Near bottom left is the little packet of fixings.

Lovely find.

May be a challenge to assemble correctly with bevel drive to the valve. The strip material is cylinder cladding.

Not sure it's fully machined. No exhaust or mounting holes, looks like just the tricky bits are done, but not the simpler drill and tap bits?

Neil

Edited By Neil Wyatt on 23/04/2018 19:54:38

£2-3s-6d, oh happy days! Mind you I wonder what the average wage was at that time. If only we could have those prices along with todays wages. One can but dream.

Doug

https://imgur.com/a/2HxAA1E
Link to album with a close up of parts.

Edited By JasonB on 23/04/2018 20:08:35

Blow i up large enough and the holes are there just hard to see through the old plastic.

The small stepped bush next to the wrist pins goes into the "banjo" and takes the eccentric pin from the vertical shaft.

Neil has answered what the strip a "blued" steel is for.

There are not many parts to this engine and the sectioned assembly on the drawing I linked to will show where all the bits go and it shows the timing arrangement too.

Edited By JasonB on 23/04/2018 20:11:45

Well, a massive thank you to everyone for all your input. It seems I have a relatively valuable piece of kit here?? I will be keeping a hold of it for now. perhaps within a week or so when "an expert" has seen this in the flesh and can give me a ballpark value figure, I'll chuck it up on Ebay. If there's a better place to be selling this I'll gladly post there too. Naturally though this has spurned on my interest in these things, can anyone recommend a kit in the region of 200-300 that's half decent?

I have just finished a Sun engine machined from castings it makes a nice engine and it ran first time on air.