Unusual/Interesting Engines/Motors
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Re: Unusual/Interesting Engines/Motors
I came across this unusual supercharged, 2 stroke diesel that is a candidate for this thread. What do you think?
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Re: Unusual/Interesting Engines/Motors
Is that a "Commer Knocker" ?Dormouse wrote: 02 Feb 2023, 08:41 I came across this unusual supercharged, 2 stroke diesel that is a candidate for this thread. What do you think?
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Re: Unusual/Interesting Engines/Motors
Yes, it is the Commer Knocker. A most unusual combination of rocker operated conrods to give a single output crankshaft.
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Re: Unusual/Interesting Engines/Motors
If you ever wondered how a Triple Expansion Engine worked, try this.
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Re: Unusual/Interesting Engines/Motors
At my motor club committee meeting last night, one of the members showed me some pages about a Rolls Royce engine he's writing about for a book. It's a 6 cylinder, 12 piston, twin crankshaft, multi-fuel design. Not sure if it's been mentioned here before but here's something about it I found on the web.
The Rolls-Royce Opposed-piston K series Engine
https://archive.commercialmotor.com/art ... on-engines
The Rolls-Royce Opposed-piston K series Engine
https://archive.commercialmotor.com/art ... on-engines
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Inside every old person is a young person wondering what the hell happened.
"Trying is the first step towards failure" ~ Homer J Simpson?
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Re: Unusual/Interesting Engines/Motors
This engine uses a Roots Supercharger too and, interestingly, uses 2 intermediate Gears to link the crankshafts - the crankshafts are therefore counter rotating. This puts the thrust side of each set of pistons on the same side of the block and crankshaft couples counter each other. All in all, a powerful compact unit.
Scrub that! I have looked at a better, clearer online diagram. The upper and lower cranks drive a third intermediate Output Shaft allowing Individual Crankshaft Phasing to change the Torque Characteristics. Very sophisticated.
Scrub that! I have looked at a better, clearer online diagram. The upper and lower cranks drive a third intermediate Output Shaft allowing Individual Crankshaft Phasing to change the Torque Characteristics. Very sophisticated.
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Re: Unusual/Interesting Engines/Motors
Further reading links this engine, the Commer Knocker and the Leyland L60
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Re: Unusual/Interesting Engines/Motors
It's a screamer!

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Re: Unusual/Interesting Engines/Motors
Have a squidge at this one
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Re: Unusual/Interesting Engines/Motors
And on the back of that, have a look at this one
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Re: Unusual/Interesting Engines/Motors
Triple expansion steam engines can be remarkably efficient - rivaling modern diesels - from memory can be up to 35% efficient, which is pretty phenomenal given the "old technology"Dormouse wrote: 02 Feb 2023, 09:53 If you ever wondered how a Triple Expansion Engine worked, try this.
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Years ago I went on a steam powered boat called The Waverley. Went in the engine room and can still recall the fantastic smell (steam, hot oil) I think that was triple expansion too.
Can't help wonder if we could up the efficiency again further= quadruple expansion seems the obvious next step! Fourth stage would need a MASSIVE cylinder though, perhaps there's so little energy left after 3 expansions and deminishing returns makes it pointless
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Re: Unusual/Interesting Engines/Motors
Me too Matt, a fascinating day out, I saw her in Plymouth!

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Re: Unusual/Interesting Engines/Motors

https://en.wikipedia.org/wiki/PS_Waverley
Just had a read, remembered correctly, triple expansion.
Wow, have to say very surprised how recently built it is - 1946, would have guessed a decade or two older than that!
Like you say, fascinating thing to explore, enjoy!
I can't think where I'd have been on it other than lake coniston, if it's ever been there?? Says seafaring, but can't recall where I would have been to be in the sea, riding Waverley. Hmmm. Fair to say the engine room picture was very familiar, so can see my focus very much was not on the scenery we may have been sailing past!

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Re: UnusuIf I remember al/Interesting Engines/Motors
If I remenber correctly she used to work from Liverpool up to Glasgow via various intermediate stops so anywhere up that coast is a possible. She also made some trips down the Irish sea, through the channel and up ro Greenwich I believe which is how I saw her in Plymouth! 

I used to be indecisive, now I'm not so sure!
I used to ride on two wheels, but now I need all four!
I used to ride on two wheels, but now I need all four!