Engines > Restoration of Model Engines
Stevens's Model Dockyard- Marine engine
vtsteam:
I love that engine! :ThumbsUp: :ThumbsUp: :cheers:
Sanjay F:
--- Quote from: Jasonb on January 11, 2026, 01:46:41 pm ---I don't bother looking at the valve when setting the timing.
First with the cylinder removed check the valve is moving to expose equal amounts of port top and bottom by holding teh cylinder port face at right angles to the valve chest. It may help to put a piece of masking tape down the cylinder and use a fine pencil to mark the port positions to you can better judge valve position.
Then you can set the timing based on the high point of the eccentric. A good rule of thumb is to have the high point of the eccentric leading the crank pin by 90deg plus another 30 degrees. So while the crank is upper most at 12 o'clock you want the high point of the eccentric at either 4 or 8 o'clock depending on which direction you wnat the engine to run.
I'd say is is a No248 which was also in my 1919 catalogue.
--- End quote ---
I have marked TDC on the flywheel with an arrow and the eccentric is currently also set at 12 o'clock with the shortest distance which is clearly incorrect as it needs to be the 'high point' as you call it, at 90 deg plus 30. I think the high point is the arrow I've marked in the photo? Basically 180 degs from where its currently positioned?
Jasonb:
That's it at the bottom as marked on the photo, no real need to mark the flywheel when you can just look at the crank pin at the other end
Jasonb:
--- Quote from: vtsteam on January 11, 2026, 02:08:33 pm ---I love that engine! :ThumbsUp: :ThumbsUp: :cheers:
--- End quote ---
Yes, almost tempted to add it to my Future projects list. Ideal candidate for a bit more 3D printed metal. But then I would have to do the oscillating version too :-[
Sanjay what size engine is it, from the photos I would assume the smallest?
Sanjay F:
Yes, I think it's the size 1, 3.5" tall
I have tried from 3 o'clock to 5 o'clock incrementally and the video shows 4 o'clock, she's trying to go but if you listen there is the sound of the exhaust throughout. This is happening in all positions, so I think another dismantle and checking the ports using your masking tape method may be called for.
The pin in the scotch yoke is a pain, its either too tight and jamming things up or too loose and striking the guide. I may use a bit of super glue temporarily on the lock nut to hold it in the correct position
https://www.youtube.com/shorts/yuZof_bfMls
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