3 Cylinder Life

HGM · Feb 8, 2006

Ok, I guess it doesnt make sense to me.... /forums/images/graemlins/confused.gif

How could a 3cyl produce more Tq than a 4cyl? I honestly dont know any different, but I cant see logicaly how this would be true.. Anyone able to explain this?

BGL990 · Feb 8, 2006

I'll take a stab at it ...

I believe the key bit of the comment was that a 3 cyl. makes more torque than a 4 cyl. of the same displacement

To get an engine of the same displacement with less cylinders, each of those cylinders must be of larger displacement. Larger displacement requires either larger diameter or longer stroke, or both. Both of those things will increase low end torque, especially the longer stroke.

... awaiting corrections ... /forums/images/graemlins/grin.gif

HGM · Feb 8, 2006

OK, I'll buy that one... Missed the "equal size" part... Thanks..

varmint · Feb 13, 2006

Years ago, I saw a small 3 cylinder Cat diesel that was driving a stationary generator... about the same sized engine as a CUT, but different operating situation, of course. The owner told me that such rigs typically get 12,000 hours between overhauls.

jimgerken · Feb 15, 2006

There will be a relationship between the hours you work it AT EACH SESSION, and the total hours you will get out of it. A study of skid steer loaders recently showed that the loaders which were operated for short periods each time they were started, typically wore out the cylinders due to corrosive buildup, or something like that. It seems from memory that the cylinders develop a wear taper fairly rapidly if operated in this short-run manner. I will try to find the study I am (half) remembering...
Found this, not the article I was remembering, but well worth reading...
http://www.constructionequipment.com/article/CA6256027.html

Sully2 · Feb 15, 2006

</font><font color="blue" class="small">( I'll take a stab at it ...

I believe the key bit of the comment was that a 3 cyl. makes more torque than a 4 cyl. of the same displacement

To get an engine of the same displacement with less cylinders, each of those cylinders must be of larger displacement. Larger displacement requires either larger diameter or longer stroke, or both. Both of those things will increase low end torque, especially the longer stroke.

... awaiting corrections ... /forums/images/graemlins/grin.gif
)</font>

Why does "cylinders" have anything to do with it? DISPLACEMENT! an 800 cy. in single cylinder can easily have more torque that a 3; 4 or 6 cylinder of say..?...50 cubic inches.

Soundguy · Feb 15, 2006

I believe he was trying to say, that given 2 engines with equal displacement, the one with less cyls will have more torque.. etc

Soundguy

bikemiser · Feb 16, 2006

So if I have this right an old two cylinder JD will out pull a six cylinder Oliver. Why doesn't anyone make a large two cylinder tractor anymore?

Soundguy · Feb 16, 2006

If they are the both CID.. I'd say the 2 cyl should have more low end torque.. etc..

Chinese were sending over 2cyl diesels in the jinma line just recently..

Soundguy