Why?

Loner16

Member

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B-7800
Before buying my B-7800, I was a babe in the woods concerning diesel engines. Not a genius now, but I get around.
Anyway, when I read the manual, I was surprised to learn that the 4 cylinder Kubota engine fired "2 up, 2 down." Don't really know why that is, unless it has something to do with torque values. So, I've been considering upgrading to an L-3800/3901, although I can't imagine being parted from my beloved B-7800.
But, the L is a three cylinder, so how does that fire? Two up, one down, or a more balanced firing order?
 

ipz2222

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The 2 up, one is fireing and one is on the exhaust stroke. You get a power pulse every 180 degrees of rotation. Never have looked at the 3 cylinder.
 

cerlawson

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Feb 24, 2011
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Why don't you put a title to your threads that has some meaning for those that may be of help, instead of leaving us all to wonder and waste our time.
 

85Hokie

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Before buying my B-7800, I was a babe in the woods concerning diesel engines. Not a genius now, but I get around.
Anyway, when I read the manual, I was surprised to learn that the 4 cylinder Kubota engine fired "2 up, 2 down." Don't really know why that is, unless it has something to do with torque values. So, I've been considering upgrading to an L-3800/3901, although I can't imagine being parted from my beloved B-7800.
But, the L is a three cylinder, so how does that fire? Two up, one down, or a more balanced firing order?
Loner,

take a look at this thread from a while back:

http://www.orangetractortalks.com/forums/showthread.php?t=9671
 

ShaunRH

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It is a friendly place but folks can get grumpy for various reasons... we should all be as forgiving as we can.

Anyway, 3 cylinders have traditionally been tough. If you fire them based on a 120° rotation it's mathematically sound, but I think actual timing is a bit different. Optimally we'd have 3 cylinder radial engines, tons of torque and good HP as well but we seem to have forgotten radials in the pursuit of water cooled technologies, but even radials can be water cooled so why is a mystery to me.

Older 3 cylinders run a little rough but the one on my L3200 is smooth as silk.
 

Bluegill

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The smoothest diesel I've ever been around is the 5 cyl in our old L3750. Not seen any other 5 cyl engines in tractors. This thing is completely vibration free.
 

ipz2222

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cerlawson is not being grumpy.. If i want to search for a paticular problem, I sure wouldn't search the titles for "why" .. A different and maybe better title would be "difference in 4 cyl and 3 cyl".
 

Lil Foot

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cerlawson is not being grumpy.. If i want to search for a paticular problem, I sure wouldn't search the titles for "why" .. A different and maybe better title would be "difference in 4 cyl and 3 cyl".
I have to agree- I've wasted a lot of time searching for old threads with good info, only to find the reason the search was unsuccessful was that the title was un-related to the subject.
 

Loner16

Member

Equipment
B-7800
Well, maybe the grump wasn't being grumpy .. Perhaps it's just the old problem that the internet has always suffered from ... A total lack of respect for others from the safety of a keyboard. In any case, I see no reason for it, and no tolerance for the behavior.
Some want their boards to grow, others, perhaps do not care, but this is what drives away potential members. I read much more than post, and this is one of the reasons why. I could respond in kind, but I would not feel very good about myself, and it would only serve to reduce me to the other person's level ... And, most of all, I enjoy looking in the mirror to shave, and liking what I see.

So, thanks to those who provided answers to what I consider a valid question. And for those that get their kicks from abusing whom they consider to be a newbie who does not know the ropes .... Carry on, I have no more taste for the aggravation!
 

ShaunRH

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I can't speak for anyone else but when I'm doing a search I usually don't rely on titles, I want the stuff in the content of the thread more than the title (which can be misleading as a problem stated in the title frequently deviates to a different issue entirely) so a title like "Why?" doesn't bother me. It is informative, no, but it might have people looking at my post that normally wouldn't and might get more opinions on the issue, so regardless it is a valid title. If you don't like the title, you don't have to read the thread. If you feel like you got scammed, then chalk it up to "Hey, I shouldn't read abbreviated title threads."

Don't get me wrong, I'm not defending the choice of title, but I am defending the right to create an ambiguous title without feeling like I'm going to be battered about for it. Go with the flow guys and nicely worded suggestions for improvement with a positive message are usually welcomed by all. Just my observations though, I could be wrong.
 

cerlawson

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Mr.Loner: Sorry if I ruffled your beard. I blame my approach on my education and work. As a clvii engineer I frequently have to look up a subject in my reference books. In using an index I sometimes come across a situation where the single reference word has mulitple pages tied to it, yet the index has limited sub-headings. Being that time is always an issue these days, I get frustrated having to thumb through the book to find the right section. Not only in my work, but take a typical tool catalog. Take up a Northern Tool catalog and look up "batteries" and you will see what I mean. If time means nothing, well that's OK.
 

uncle carver

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The problem with the internet is people get upset at simple statements.
some types "Use a better title" People hear "Use a better title you jerk".
I like the better title idea.