Still a New "B" here~~~

[BILL WZOREK]

Lately there has been talk on here about Balancing Crank /Rods / Flywheel / Pistons
Basically the spinning mass ~
Could some one please explain using small words ( Like in school I am still sitting at the back of the class room ) How each part of this is done.

[A bones]

Morning Bill, try cllicking on this site lots info including Reds + Car Craft. https://www.google.com/#q=how+to+balance+a+v8+engine

[JSeery]

In little words (and over simplified) you weight all the parts (pistons, rings, rods, piston pins, etc.) individually and get them to match each other. So, you would weigh all the pistons, find the lightest one and then get all the other pistons to match that weight. And so on with all the individual parts. Then you add up the weight for one cylinder (again, piston, pin, rings, rods, etc.) and use a math formula to come up with what is called a bob-weight. This weight is placed on each crank throw to the represent the weight of the parts that would be there in the engine. The crank is placed in a balancing machine and spun at different rpm. The machine tells you where the crank is out of balance and weight is added or removed to get it into balance. Then you can add things like a flywheel and balance it as part of the assembly, and so on. The only part that is different are the rods, they have to not only match weight as a whole, but for each end. So, all the small ends have to match and all the large ends have to match. That is a simplified version of it.

If you are interested in detail you might want to read some of the links A bones posted.

[Mart]

There was a very good description of the balancing process on the Old Henry rebuild thread.

Mart.

[BILL WZOREK]

Originally Posted by JSeery

In little words (and over simplified) you weight all the parts (pistons, rings, rods, piston pins, etc.) individually and get them to match each other. So, you would weigh all the pistons, find the lightest one and then get all the other pistons to match that weight. And so on with all the individual parts. Then you add up the weight for one cylinder (again, piston, pin, rings, rods, etc.) and use a math formula to come up with what is called a bob-weight. This weight is placed on each crank throw to the represent the weight of the parts that would be there in the engine. The crank is placed in a balancing machine and spun at different rpm. The machine tells you where the crank is out of balance and weight is added or removed to get it into balance. Then you can add things like a flywheel and balance it as part of the assembly, and so on. The only part that is different are the rods, they have to not only match weight as a whole, but for each end. So, all the small ends have to match and all the large ends have to match. That is a simplified version of it.

If you are interested in detail you might want to read some of the links A bones posted.

So the crank Balancing machine is more then just a lathe / Does any one have a picture of one??

[JSeery]

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Posted some balance machines and some of the bob-weights, might give you an idea of what is going on. The balance machine has to tell you where the out of balance issue is.

[Kurt in NJ]

Here is a video of the process--
https://www.youtube.com/watch?v=ReknvNVg5m8

here is one you can make yourself--
http://antiqueautoranch.com/montana5...ter/page4.html

[JSeery]

Thanks interesting. Here is a video on the whole process.
https://www.youtube.com/watch?v=M_PeWKnTchI

[51 MERC-CT]

How do Ya' balance a flathead?

[BILL WZOREK]

Originally Posted by 51 MERC-CT

How do Ya' balance a flathead?

This has to be a American built Flathead ~~ the counter weights
are in #'s and not Kilo's LOL

[dean333]

Fabulous video in post #8, I never knew! Thanks!