Model Boat Mayhem
The Shipyard ( Dry Dock ): Builds & Questions => Steam => Topic started by: MOG8 on May 02, 2011, 10:50:58 pm
-
I have been asked to identify this engine.
Aside from the obvious similarities I have never seen this particular engine before.
A help from the Forum members could bring a positive answer.
Thank you.
-
The casting P' - S....may give the nationality away ....a French version of a Uniflow engine? ............Derek :o
-
This engine is located in Canada and it is pretty old, if this is of any importance...
-
Looks like a Stuart Turner Sirius or a derivative of one.
LB
-
Liverbudgie ...was not the ST Sirius a latter derivative of the ST Uniflow engine?........but the latter with horizontal piston valve timing actuation rather than the bevel geared rendition as displayed? :o >:-o ...Derek
-
Hi Giovanni,
Sorry that I can't say who made the engine but can say that it is not a Uniflow engine, to my knowledge Stuart never made a Uniflow engine.
It looks as though it has been designed on the Stuart high speed engines, STAR, SUN and SIRIUS engines which were twin cylinder single acting piston valve engines of inside admission, all of which were driven by bevel gear and shaft to the overhead piston.
Uniflow engines have slots at the bottom of the cylinder to let the exhaust escape into a jacket at the bottom of the stroke, or in early engines the exhaust was allowed to vent into the atmosphere.
Here are some pics of a Uniflow Poppet valve high speed engine, showing the exhaust slots at the bottom of the cylinder.
(http://s1.postimage.org/dhu1lhc4/Complete_engine_2.jpg) (http://postimage.org/image/dhu1lhc4/)
(http://s1.postimage.org/di0nqvb8/Complete_engine_4.jpg) (http://postimage.org/image/di0nqvb8/)
(http://s1.postimage.org/difjkzr8/engine_4.jpg) (http://postimage.org/image/difjkzr8/)
Hopefully somebody may be able to throw some light on the maker.
George.
-
:embarrassed: ...opps....clearly I have had my engine names mixed up here......... <*< ...Derek
-
This looks very like a Stuart MTB1 which dates from the late 1920s - early 30s. Mine has had any identification marks on the sides of the crankcase machined off. It is the same size as the Sun engine at 3/4" bore and stroke. I seem to remember that I was once told that originally this engine had a slide valve instead of a piston valve - maybe there was a design changs along the way.
Malcolm
-
Malcolm,
There are so many things in common with your engine that would make me think that yours is the prototype for Giovanni's engine.
Firstly your engines vertical drive has the bottom bracket bolted to the casting as is the top and your valve is driven by a Scotch crank.
On Giovanni's engine the bottom support is cast into the main casting and the top one is part of the cylinder head casting, not sure how the valve is driven as the pic isn't too clear, at a later date they went to the hair pin type drive.
So possibly your engine was made before Stuart's went ahead with the new casting holding all the bracket supports, Just a guess on my part.
They did make a Sun engine with a slide valve but it proved unpopular with the racing fraternity as the valves were melting and sticking due to the high temps and pressures.
Hope fully somebody will come up with an answer.
George.
-
George
Giovanni's engine looks to be a bit larger than mine. Stuart made a rande of MTB engines - I've got a list somewhere, but can't find it at the moment. The MTB3 has a bore of 1.25" with a stroke of 1", and there are quite a few differences in the design as you can see. I expect that the Nos. 1,2 &3 engines all differed in detail so this could be the reason that Giovanni's and my engines are slightly different.
Malcolm
-
Thank you for the guessing work done so far.
It take the opportunity given by George to show the SUN engine with slide valve,
Do you know the period in which it was produced?
Thank you.
(http://farm6.static.flickr.com/5250/5687125838_53af483b92.jpg) (http://www.flickr.com/photos/35088074@N03/5687125838/)
STUART TURNER SUN. SLIDE VALVE (http://www.flickr.com/photos/35088074@N03/5687125838/) by STEAMPROPULSION (http://www.flickr.com/people/35088074@N03/), on Flickr
-
(http://s3.postimage.org/1esjqzmtg/Stuart_Sirius_Gen_Set_4.jpg) (http://postimage.org/image/1esjqzmtg/)
In it's original gen set set-up
-
my Stuart No.2 Torpedo Boat Engine
(http://farm5.static.flickr.com/4080/4934001689_37ee714288_b.jpg)
(http://farm5.static.flickr.com/4140/4934596828_5bbd70731b_b.jpg)
-
Hi Logoman,
There are similarities on your engine and the one that I am asking about.
---The cylinder head with the built in steam chest are the same but the cover is different.
--the slide valve rod brass packing gland cover is the same.
-- the rocking arm brass bracket is the same.
I think that this is probably a 1- off by Stuart but I hope some body can tell me different.
George.
-
George, I've lost track of which engine you are asking about.
-
Sorry M.
I got a bit side tract and posted on the wrong thread here is my original post and you can see quite a few similarities.
http://www.modelboatmayhem.co.uk/forum/index.php?topic=31619.0
I would appear that this engine is a bit of a high brid using the main castings and making the other bits to suit .
George.