Running engine (diesel) with the ignition turned off

[convey]

So you are correct and multiple experienced posters are wrong?

Yes, although it's more a question of at a greater depth and acuity rather than right and wrong. Paul was right at the most simplicistic level, but apparent couldn't think things through any further to the how and why.

Same's going on with valve train geometry.

Engineering's based on maths and in both cases what is right is not based on a democratic vote down the pub.

Does it matter on low tuned, low stressed agricultural engines that only do 10s of hours work each year? Probably not.


How do you measure deck height with a dished piston? The same way you measure deck height on a flat headed piston ... only obviously not in the dish. Personally, I made up my own deck bridge and use a dial indicator. A flat edge is always useful to have a hand.

People have really got to stop using the "you read it on Google" put down. In case you have not noticed, basically every trade, scientific and academic paper or journal (and most experts) are "on Google". It's a good tool to expand your knowledge and keep up with both historical and latest info ... as if I really have to say that. The art has become shifting through all the chaff and filtering out all the echoes of bad information.

 

[rogerthebodger]

Engineering's based on maths and in both cases what is right is not based on a democratic vote down the pub.

Engineering maths is like most scientificentic applications are based on peer review which is a democratic vote which for most Engineers takes place down the pub.

Of cause if you don't respect the peer review process that seems very self centered and arrogant.

Steven Hawking's university prof never accepted his theories which was accepted by the scientific community after review by a number of his peer.

One of the interesting and most important facts is the definition/application of the forces involved before the application of the maths. The possibility of a fault in your definition also must be considered i.e. the consequences of an fault in the application of the maths.

 

[Beneteau381]

Engineering maths is like most scientificentic applications are based on peer review which is a democratic vote which for most Engineers takes place down the pub.

Of cause if you don't respect the peer review process that seems very self centered and arrogant.

Steven Hawking's university prof never accepted his theories which was accepted by the scientific community after review by a number of his peer.

One of the interesting and most important facts is the definition/application of the forces involved before the application of the maths. The possibility of a fault in your definition also must be considered i.e. the consequences of an fault in the application of the maths.

I am confused! He is a very clever person! isnt he?

 

[RichardS]

How do you measure deck height with a dished piston? The same way you measure deck height on a flat headed piston ... only obviously not in the dish.

Here we go again, Convey.

You disagree with something Paul says, Paul tells you that you are wrong, and you then change your mind and agree with Paul .... but you will fight to the last ditch to deny that you are now actually agreeing with him.

Richard

 

[convey]

Richard,

fluff Paul all you like in private but pretty much all you've done in this discussion is to make noise by misrepresenting both my position and, now, the events.

Paul never made a statement about measuring deck heights. He asked a question. I answered it specifically both re theory and practice.

How is that "agreeing"?

I have no idea where that line of dicussion is going to lead or how it will be relevant yet.

Hope he's washed first and tastes nice.

Engineering maths is like most scientificentic applications are based on peer review which is a democratic vote which for most Engineers takes place down the pub.

If I was going to be macho, I could respond by saying that, no, in motor engineering, they are settled on the race track, but the stuff we're talking about was settled about 100 years ago.

If I make an appointment down the IMechE for a second opinion, are you going to turn up? I'm afraid I don't accept a barman as a final arbiter.

 

[RichardS]

Richard,

fluff Paul all you like in private but pretty much all you've done in this discussion is to make noise by misrepresenting both my position and, now, the events.

Paul never made a statement about measuring deck heights. He asked a question. I answered it specifically both re theory and practice.

How is that "agreeing"?

Paul said ""deck height" and "squish" have now been thrown into the mix. Deck height is simply the distance between the top of the piston (at it's perimeter in the case of dished or domed pistons) and the surface of the cylinder block."

You replied "I presume you're reading the stuff about deck height and squish at the perimeter off a website ... because it's also crap. Deck height and squish are measurements right across the piston and wherever the face of the head exists."

Paul said "Seriously? How do you measure the height of a dished piston?"

You replied "Which do you mean, the pin height, the crown height, or the volume of the dish or bowl?"

Paul replied "As my comment was in response to one of your idiotic "deck height" and "squish" remarks, it's pretty obvious what i meant. So, answer the question, where do you take the measurements for deck height and squish with a dished piston?"

You have never replied to Paul's final question because you have realised that you were talking absolute nonsense yet again ...... so you have now qualified your position by saying in your post #261 above "How do you measure deck height with a dished piston? The same way you measure deck height on a flat headed piston ... only obviously not in the dish " which is exactly what Paul stated in his first quote and not "right across the piston" as you stated.

So, as I said, you have gone full circle and are now agreeing with Paul, as you do every single time on this thread. Being Convey must be somewhat of an embarrassment at times like this.

Richard

 

[rogerthebodger]

If I was going to be macho, I could respond by saying that, no, in motor engineering, they are settled on the race track, but the stuff we're talking about was settled about 100 years ago.

Well as a retired development Engineer things are never settles in any Engineering and scientific displine there will always new and improved developments. Thats how we have developed over time

If I make an appointment down the IMechE for a second opinion, are you going to turn up?

I would if I could but there are not international flights out of Johannesburg to London. I birdcage walk can easy be reached from Heathrow if only I couls get there.

I take it you are a Member of IMechE so a Chartered Engineer.

There are a number of members of this forum who are or have been a Member of IMechE so a Chartered Engineer including people who you rubished.

I'm afraid I don't accept a barman as a final arbiter.

It was you who menchede the pub and who said the barman was to be the arbiter. There were plenty of Engineers in the pub when I lived in the UK

 

[penberth3]

….I take it you are a Member of IMechE so a Chartered Engineer......

I've asked the engine expert three times about his/her qualifications. I'm not expecting personal detail, just an outline. I've had no reply. In fact, nobody is getting a straight reply to a question. Not good communication if he/she is a professional engineer.

 

[rogerthebodger]

I've asked the engine expert three times about his/her qualifications. I'm not expecting personal detail, just an outline. I've had no reply. In fact, nobody is getting a straight reply to a question. Not good communication if he/she is a professional engineer.

Of cause he won't answer a straight question with a straight answer which tells me he hiding something and is not associated with any professional control body particular any engineering institution as these require a high level of integrity and honesty.

 

[Skylark]

If I was going to be macho, I could respond by saying that, no, in motor engineering, they are settled on the race track, but the stuff we're talking about was settled about 100 years ago.

Not really sure what “motor engineering” is but your comment suggests a lack of understanding as to how the automotive industry works. It does sound as though you’ve read too many macho car magazines, though ?

 

[convey]

If you don't know what motor engineering is, then you hardly belong in this discussion.

Or did you guys take a democratic vote and decide it didn't exist?

Do you want to check the phonebook to find out how many is motor engineering companies there are in this country? You won't believe me, so call anyone of them up and ask them ... but please record it so we can all hear.

Paul said

Paul said

Paul replied

As I wrote Richard, all you're doing now is talking shit to add distracting noise while sucking up to Paul.

Deck height relates to the top surface of block, not the shape of the piston. Therefore the deck height will be the same at the edge of the piston, as in the centre of the dish, or even at the middle/inside of a domed piston that protudes above it.

Paul has yet to tell us where this line of questioning is going, or to tell you whether I was right or wrong in either my theory or methodology.

 

[Skylark]

If you really knew what you were talking about, in relation to the fundamentals of engine design technology, you'd use the correct terms.
You seem to be referencing different things with a common name.
The Reeds publication is a good example. They use motor and engineers as colloquialisms for engine and technicians.

 

[RichardS]

Deck height relates to the top surface of block, not the shape of the piston. Therefore the deck height will be the same at the edge of the piston, as in the centre of the dish, or even at the middle/inside of a domed piston that protudes above it.

Paul said "Deck height is simply the distance between the top of the piston (at it's perimeter in the case of dished or domed pistons) and the surface of the cylinder block."

You replied "I presume you're reading the stuff about deck height and squish at the perimeter off a website ... because it's also crap. Deck height and squish are measurements right across the piston and wherever the face of the head exists."

Paul said "Seriously, where do you take the measurements for deck height and squish with a dished piston?"

You have never replied to Paul's final question because you have realised that you were talking absolute nonsense yet again ...... so you have now qualified your position by saying in your post #261 above "How do you measure deck height with a dished piston? The same way you measure deck height on a flat headed piston ... only obviously not in the dish " which is exactly what Paul stated in his first quote which you said was "crap".

So, was Paul's statement that "Deck height is simply the distance between the top of the piston (at it's perimeter in the case of dished or domed pistons) and the surface of the cylinder block" a correct statement or was it "crap" as you stated above?

I'm not surprised that your sole supporter, Tamarside, has fallen totally silent. He must be ruing the day that he ever believed that you had the slightest clue about motor engineering.

Richard

 

[Beneteau381]

If you really knew what you were talking about, in relation to the fundamentals of engine design technology, you'd use the correct terms.
You seem to be referencing different things with a common name.
The Reeds publication is a good example. They use motor and engineers as colloquialisms for engine and technicians.

Marine Engineer always gets me, used in the context "the marine engineer said" marine engineers my ass! I remember the first one I met in Scotland years ago, we were on a converted wooden fishing boat on a diving trip. Had an old Gardner, the starter motor wouldnt work, the so called marine engineer diagnosed a knackered starter, myself and the club chair took a look, it was full of oil, so was the bell housing! The so called marine engineer was a thumblethumbs shade tree mechanic! We drained the bell housing, the skipper had been continually filling the gearbox, we told him to leave it, let it find its own level just below the seal and fix when we got back to the home port, just keep an eye on it, and we stripped the starter, washed it all in petrol, let it dry, re assembled it and away it went! Marine engineer my backside!

 

[rogerthebodger]

Marine Engineer always gets me, used in the context "the marine engineer said" marine engineers my ass! I remember the first one I met in Scotland years ago, we were on a converted wooden fishing boat on a diving trip. Had an old Gardner, the starter motor wouldnt work, the so called marine engineer diagnosed a knackered starter, myself and the club chair took a look, it was full of oil, so was the bell housing! The so called marine engineer was a thumblethumbs shade tree mechanic! We drained the bell housing, the skipper had been continually filling the gearbox, we told him to leave it, let it find its own level just below the seal and fix when we got back to the home port, just keep an eye on it, and we stripped the starter, washed it all in petrol, let it dry, re assembled it and away it went! Marine engineer my backside!

What is a Engineer ?

The word engineer (Latin ingeniator) is derived from the Latin words ingeniare ("to create, generate, contrive, devise") and ingenium ("cleverness")


https://en.wikipedia.org/wiki/Engineer

This dos specify what qualifications, work practice and peer review is need to be a qualified Professional Engineer.

This give some definition which does not include Marine Engineer as depending on which particular part of the marine environment you work in is part of Mechanical Engineering or Civil Engineering.

In the USA an Engineer was a steam locomotive driver.

 

[Rustyknight]

I guess someone has to do it....

 

[JumbleDuck]

I'm not surprised that your sole supporter, Tamarside, has fallen totally silent.

 

[PaulRainbow]

Paul said ""deck height" and "squish" have now been thrown into the mix. Deck height is simply the distance between the top of the piston (at it's perimeter in the case of dished or domed pistons) and the surface of the cylinder block."

You replied "I presume you're reading the stuff about deck height and squish at the perimeter off a website ... because it's also crap. Deck height and squish are measurements right across the piston and wherever the face of the head exists."

Paul said "Seriously? How do you measure the height of a dished piston?"

You replied "Which do you mean, the pin height, the crown height, or the volume of the dish or bowl?"

Paul replied "As my comment was in response to one of your idiotic "deck height" and "squish" remarks, it's pretty obvious what i meant. So, answer the question, where do you take the measurements for deck height and squish with a dished piston?"

You have never replied to Paul's final question because you have realised that you were talking absolute nonsense yet again ...... so you have now qualified your position by saying in your post #261 above "How do you measure deck height with a dished piston? The same way you measure deck height on a flat headed piston ... only obviously not in the dish " which is exactly what Paul stated in his first quote and not "right across the piston" as you stated.

So, as I said, you have gone full circle and are now agreeing with Paul, as you do every single time on this thread. Being Convey must be somewhat of an embarrassment at times like this.

Richard

Thanks for posting this Richard, it is exactly what i was going to do and why i asked the question of how to measure deck height of a dished piston.

Convey obviously forgot about his earlier remark " "I presume you're reading the stuff about deck height and squish at the perimeter off a website ... because it's also crap. Deck height and squish are measurements right across the piston and wherever the face of the head exists."

 

[PaulRainbow]

Deck height relates to the top surface of block, not the shape of the piston. Therefore the deck height will be the same at the edge of the piston, as in the centre of the dish, or even at the middle/inside of a domed piston that protudes above it.

What utter rubbish, you clearly don't have the faintest idea.

Look back at some of your previous drivel, in particular the drawing you posted, showing all the the different measurements etc.

 

[convey]

You keep throwing insults up, but not actually substantiating or countering the statements.*

You keep avoiding answering questions that was expose your lack of knowledge.


I'd like to see you measure it accurately in any other way.

In short, you're only impressing people who have not got a clue about what's being spoken about.

What's offensive is that muddying up the waters and discrediting what's absolutely true.

My boat versus your boat in front of a third party expert at the IMechE any day you want ...​

--

* (If you're now going to change discussion from simple deck height to the full designed block deck height, that's a separate issue. In practise, you wouldn't and couldn't do it accurately).