convey
N/A
So sayeth the man who said piston shape has no effect on compression ratios which is where all this started off. Are you still sticking to that?
Running engine (diesel) with the ignition turned off
- Thread starter Robert Wilson
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rogerthebodger
Well-known member
Ho you mean a cylinder liner. why did you not say so.
Now are you talking about dry liners or wet liners they are fitted differently.
Its attention to detail in the real world that matters.
So what i this 1958 MD then
The only MD I can think of is Mcdonnell Douglas so are you talking about aero engines again.
RichardS
N/A
Convey is as nutty as a fruitcake. I can't remember any forumites before who are this consistently daft and who I've bothered to take an interest in. However, it really is great entertainment seeing what he comes out with next. He's quite happy to contradict statements he made a few days earlier and just doesn't seem to realise what he's saying. It's brilliant.
Richard
RichardS
N/A
Errrrr ..... I thought that we had moved on when YOU stated "piston shapes don't make the compression, but their shapes and their match determines the compressed volume, that determines the compression ratio".
Here's a thought .... why don't we go through the entire set of arguments again, starting with your first entry into this thread. You can then entertain us all over again by stating something, then retracting it, then re-stating it, ad nauseam. Let's see who's last man standing.
Richard
penberth3
Well-known member
Convey is as nutty as a fruitcake. I can't remember any forumites before who are this consistently daft and who I've bothered to take an interest in. However, it really is great entertainment seeing what he comes out with next. He's quite happy to contradict statements he made a few days earlier and just doesn't seem to realise what he's saying. It's brilliant.
Richard
I hesitate to get too personal on a forum - but this could actually be someone with a learning difficulty. The obsession with irrelevant detail, unwilling or unable to engage in two-way conversation? I really don't know what to think.
RichardS
N/A
It's not uncommon for engines to have completely separate cylinder heads and rocker covers but a common cylinder block/barrel. I have some experience with those.
Much less common in small engines is where the cylinder head, cover and barrel/block are separate and it's only the bottom end which holds the crankshaft which is common. I've never worked on one of those and I very much doubt that Convey has either.
Whether he's ever heard of such engines is a moot point.
Richard
RichardS
N/A
Yes, you are right. I have assumed that he just enjoys the banter but if there is something else going on here then I would be happy to withdraw my comment.
Richard
rogerthebodger
Well-known member
It's not uncommon for engines to have completely separate cylinder heads and rocker covers but a common cylinder block/barrel. I have some experience with those.
Much less common in small engines is where the cylinder head, cover and barrel/block are separate and it's only the bottom end which holds the crankshaft which is common. I've never worked on one of those and I very much doubt that Convey has either.
Whether he's ever heard of such engines is a moot point.
Richard
Yes I am aware of engines with separate barrels aero radial engines are like that and some big diesel locomotive and big ship engines.
I am coming to the conclusion that he is talking about piston aero engines as he talked about lycoming and continental that are aero engine manufacturers.
He also spoke about a 1958 MD and the only MD I can think about is Mcdonald Douglas.
If he is we are talking about chalk and cheese.
penberth3
Well-known member
Not very small engines, but from memory air-cooled Listers - 2,3,4, or 6 separate cylinders/heads?
Also common is 2x 2-cylinder blocks on one crankcase to make 4, or 2x 3 to make 6. Or even 2+3 for 5.
penberth3
Well-known member
No, I didn't think you went too far, however tempting it might be. Just a word of caution.
It could of course be the Editor of YBW trying to increase the "click count", if so he's doing a great job!
convey
N/A
Because I am not. I am talking about a separate cylinder or set of cylinders.
And don't call me a "ho" in public.
It's part number 30 below.
This is what cracks me up, you keep trying to make me look bad, by misconstruing what I am saying, and every time you do, you end up shooting yourself in the foot displaying your own ignorance. What proportion of engines have separate cases, barrels and heads? Probably the vast majority.
Well, clearly you don't know your marine diesels then because MD is a Volvo Penta nomenclature.
Just out of interest, do you know why Volvo Penta was named Penta?
And that they used to use a "satanic" pentagram as a logo until it fell out of fashion, true or false?
No cheating and using Google now.
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rogerthebodger
Well-known member
It looks like that engine is a single cylinder is that correct . My farymann generator diesel engine is like that not a propulsion engine.
You are correct I was thinking of a supplier name not a type designation.
I have never been interested in Volvo Penta as the type of engine I am interested in are other manufactures and just marinised by volvo which I would do myself.
The same applies to vetus engines.
The engines in my boats are a Leyland truck engine and in the other is a Perkins both 4 cylinder and mechanical injection.
I have a smaller 4 cylinder Perkins in ny garage that I stripped out of a road sweeper with a triple hydraulic pump drive that I was going to marinise but have no need for it now.
You are correct I was thinking of a supplier name not a type designation.
I have never been interested in Volvo Penta as the type of engine I am interested in are other manufactures and just marinised by volvo which I would do myself.
The same applies to vetus engines.
The engines in my boats are a Leyland truck engine and in the other is a Perkins both 4 cylinder and mechanical injection.
I have a smaller 4 cylinder Perkins in ny garage that I stripped out of a road sweeper with a triple hydraulic pump drive that I was going to marinise but have no need for it now.
black mercury
Active member
Seriously?
RichardS
N/A
It just gets better and better.
He presumably means the vast majority of those engines which produce more than 5000 hp.
Richard
convey
N/A
No, actually I was thinking of the millions of small 4-stroke and 2 stroke engines in the world which, if included, would be a slam dunk.
I doubt anyone's counted but I'd say more Honda C50 engines have been produced than all the marine diesels in history (more than 100 million in 2017 alone), and certainly more than all the one piece marine diesel blocks ever.
Am I correct, or not?
Anyone care to do the homework and come up with accurate statistics, or is smear and innuendo all you have?
You're making yourself look silly and petulant.
I doubt anyone's counted but I'd say more Honda C50 engines have been produced than all the marine diesels in history (more than 100 million in 2017 alone), and certainly more than all the one piece marine diesel blocks ever.
Am I correct, or not?
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PaulRainbow
Well-known member
Who cares, you are clearly a troll.
convey
N/A
£500 for a couple of old cylinders and pistons in Volvo green. Amazing. Note crown heights of bowled pistons.
RichardS
N/A
Crikey .... were talking about single cylinder 50cc petrol engines now? In that case, In that case, I'll raise you R/C model glowplug engines.
Now, let's get back to the real meat of the trolling:
You said "I forget if anyone conceded that piston and combustion shape and deck height, actually determine compression ratio, rather than having nothing to do with it, as some argued."
You also said " "piston shapes don't make the compression, but their shapes and their match determines the compressed volume, that determines the compression ratio" .
Now, which statement do you wish to stand by? It's time to piss or get off the pot.
Richard
rogerthebodger
Well-known member
Going back to convey's optional question " How is CR calculated.
Simple using O level physics
P1 * V1 divided by T1 = P2 * V2 divided by T2
so CR will equal P2 * T1 divided by ( P1 * T2 )
So no need to even strip h engine down to measure any dimensions.
Just measure the pressure and temperature fo the gas in the cylinder when cranking.
Simple using O level physics
P1 * V1 divided by T1 = P2 * V2 divided by T2
so CR will equal P2 * T1 divided by ( P1 * T2 )
So no need to even strip h engine down to measure any dimensions.
Just measure the pressure and temperature fo the gas in the cylinder when cranking.
jbweston
Well-known member
I have a suggestion. Why don't you just put each other on ignore and then get out and go sailing?
A wise (but often outspoken) author, David Maister, said 'Life is too short to spend it working with idiots'. Leisure time is even shorter. This thread is quite entertaining for the audience in the same way a Punch and Judy show is entertaining for the audience. But we have to wonder why the participants go on repeatedly beating ecah other with sticks.
A wise (but often outspoken) author, David Maister, said 'Life is too short to spend it working with idiots'. Leisure time is even shorter. This thread is quite entertaining for the audience in the same way a Punch and Judy show is entertaining for the audience. But we have to wonder why the participants go on repeatedly beating ecah other with sticks.
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