HELP....conversion needed..

[gn69z28]

I have 2 Yanmar 3JH3 diesel engines to rebuild. I've been giving the factory manual for specs. Problem is the I can't find a conversion for the torque specs. An example of what the book gives is Main bearing bolt torque is 10.5--- 11.5 kg.m the only conversion calculator I can find converts it to 23ft lbs. And that's not right based on the size of the bolts and how tight they were. I found torque specs online for the 3JH5 engine and it gives 75ft lbs for the main bolts which seems correct but I'm not sure if the two engines use the same torque specs. I couldn't find anything specific to the engines I have. Thanks for any help.

[BigBro74]

Hey I was just looking-my “inexpensive” KD tools beam type inch pound wrench has newton meters on its scale- it came from the parts store in a pinch because none of my inch pound snap on wrenches covered that little range.....
Might be an inexpensive way to get by——
Jason

[rebelrouser]

I have 2 Yanmar 3JH3 diesel engines to rebuild. I've been giving the factory manual for specs. Problem is the I can't find a conversion for the torque specs. An example of what the book gives is Main bearing bolt torque is 10.5--- 11.5 kg.m the only conversion calculator I can find converts it to 23ft lbs. And that's not right based on the size of the bolts and how tight they were. I found torque specs online for the 3JH5 engine and it gives 75ft lbs for the main bolts which seems correct but I'm not sure if the two engines use the same torque specs. I couldn't find anything specific to the engines I have. Thanks for any help.

Just go google a torque chart for metric bolts, find torque by bolt size, hardness, and thread pitch, done it many times.
https://www.google.com/url?sa=i&source= ... 7040664540

[Olds455]

This converter says 11 kg/m is 79.5 lb/ft. 10.5 kg/m is 75.9 lb/ft

https://www.convertunits.com/from/kg-m/to/lb-ft


The conversion seems simple enough to even do manually. 1 kg/m equals 7.233 lb/ft (2.205 lbs/3.280 ft)

Divide each side by 3.280 to get lbs/ft, which should give you 7.2xxx lb/ft is equal to 1 kg/m

[Rick!]

kg•meter is not a well used torque unit especially since a kg is not a force unit (kg is a mass unit).
Basically, a kg needs to be multiplied by gravity, 9.81 meters/second^2, to convert kg to Newtons (N).
A Newton•meter is a standard torque unit in the SI system.
To convert a Newton•meter to lbf•ft (ft•lbf for those folks), simply divide N•m by 1.356.

[midnightbluS10]

kg•meter is not a well used torque unit especially since a kg is not a force unit (kg is a mass unit).
Basically, a kg needs to be multiplied by gravity, 9.81 meters/second^2, to convert kg to Newtons (N).
A Newton•meter is a standard torque unit in the SI system.
To convert a Newton•meter to lbf•ft (ft•lbf for those folks), simply divide N•m by 1.356.

Wouldn't that get you the same exact result as converting from kg/m to lb/ft, only with a lot more chance of screwing up the math making 2 conversions instead of 1?


Why do 2 conversions when you can convert straight from 1 to the other with much less math? Converting kg to lbs and m to ft isn't that difficult?

[Stan Weiss]

kg•meter is not a well used torque unit especially since a kg is not a force unit (kg is a mass unit).
Basically, a kg needs to be multiplied by gravity, 9.81 meters/second^2, to convert kg to Newtons (N).
A Newton•meter is a standard torque unit in the SI system.
To convert a Newton•meter to lbf•ft (ft•lbf for those folks), simply divide N•m by 1.356.

Wouldn't that get you the same exact result as converting from kg/m to lb/ft, only with a lot more chance of screwing up the math making 2 conversions instead of 1?


Why do 2 conversions when you can convert straight from 1 to the other with much less math? Converting kg to lbs and m to ft isn't that difficult?

Last I check that is still 2 conversions.

Stan

[gn69z28]

Olds455 thank you for that link.

[Rick!]

kg•meter is not a well used torque unit especially since a kg is not a force unit (kg is a mass unit).
Basically, a kg needs to be multiplied by gravity, 9.81 meters/second^2, to convert kg to Newtons (N).
A Newton•meter is a standard torque unit in the SI system.
To convert a Newton•meter to lbf•ft (ft•lbf for those folks), simply divide N•m by 1.356.

Wouldn't that get you the same exact result as converting from kg/m to lb/ft, only with a lot more chance of screwing up the math making 2 conversions instead of 1?


Why do 2 conversions when you can convert straight from 1 to the other with much less math? Converting kg to lbs and m to ft isn't that difficult?

The OP asked for help and got a fish and a loaf of bread thrown at him. All I did was throw him a fishing rod.
You can see that he tried to convert kg to lbf using 2.205 lb per kg and that didn't get him where he needed to be.
Sometimes it's better to know how to do simple units conversion, or dimensional analysis, to get from one measurement system to the next.
One could also argue that most modern torque wrenches have both N•m and ft•lbf scales so the only operation necessary is multiplying kg•m
times gravity (9.81, or 10 in a pinch) and then use the scale or button on the torque wrench for N•m so only a single operation is needed.
Here is a link to a units convertor that nearly every engineer I work with, including me, has on their computer.
https://joshmadison.com/convert-for-windows/

[David Redszus]

I have 2 Yanmar 3JH3 diesel engines to rebuild. I've been giving the factory manual for specs. Problem is the I can't find a conversion for the torque specs. An example of what the book gives is Main bearing bolt torque is 10.5--- 11.5 kg.m the only conversion calculator I can find converts it to 23ft lbs. And that's not right based on the size of the bolts and how tight they were. I found torque specs online for the 3JH5 engine and it gives 75ft lbs for the main bolts which seems correct but I'm not sure if the two engines use the same torque specs. I couldn't find anything specific to the engines I have. Thanks for any help.

To convert KgM to ft lbs

1 KgM = 7.233 ft lbs

[midnightbluS10]

That was posted above. Plus a breakdown of how that, number is achieved. Fish and bread? Huh?

I'm not near as smart as you are, David, and even I see that. Convert kg to lbs and meters to feet and you end up with 1kg/m = 2.2 lbs/3.28ft

Not hard to finish from there.

[midnightbluS10]

kg•meter is not a well used torque unit especially since a kg is not a force unit (kg is a mass unit).
Basically, a kg needs to be multiplied by gravity, 9.81 meters/second^2, to convert kg to Newtons (N).
A Newton•meter is a standard torque unit in the SI system.
To convert a Newton•meter to lbf•ft (ft•lbf for those folks), simply divide N•m by 1.356.

Wouldn't that get you the same exact result as converting from kg/m to lb/ft, only with a lot more chance of screwing up the math making 2 conversions instead of 1?


Why do 2 conversions when you can convert straight from 1 to the other with much less math? Converting kg to lbs and m to ft isn't that difficult?

Last I check that is still 2 conversions.

Stan

Then I guess that makes his way 3 conversions.

[Stan Weiss]

Wouldn't that get you the same exact result as converting from kg/m to lb/ft, only with a lot more chance of screwing up the math making 2 conversions instead of 1?


Why do 2 conversions when you can convert straight from 1 to the other with much less math? Converting kg to lbs and m to ft isn't that difficult?

Last I check that is still 2 conversions.

Stan

Then I guess that makes his way 3 conversions.

► 11 * 9.81 / 1.356 = 79.5796460177

► 11 * 2.2046 * 3.2808 = 79.56136848

Still looks like two conversions for each to me.

Stan

[David Redszus]

► 11 * 9.81 / 1.356 = 79.5796460177

► 11 * 2.2046 * 3.2808 = 79.56136848

Still looks like two conversions for each to me.

How about:

11 * 7.233 = 79.563

How many conversions is that?

Does anyone remember the correct use of significant digits?
Using ten more decimal places does not make a calculation more accurate.

[Stan Weiss]

► 11 * 9.81 / 1.356 = 79.5796460177

► 11 * 2.2046 * 3.2808 = 79.56136848

Still looks like two conversions for each to me.

How about:

11 * 7.233 = 79.563

How many conversions is that?

Does anyone remember the correct use of significant digits?
Using ten more decimal places does not make a calculation more accurate.

David,
I am lazy and just cut and paste the results from a calculator. So what calculator do you use that has that logic?

Stan