Hello,
I've picked up a Lister clone engine. The engine is terribly unbalanced and really wants to walk all over the place. The forces are strong enough that I think the engine will tear itself apart in a year or two if I bolt it down.
What would it take to balance these heavy flywheels? Does it sound like a local machine shop could accomplish this or would I need to talk with some specialist shop? Any idea of the cost involved?
Thanks for any insight.
Justin
Sorry, have heared Lister, but don't know how it looks. Big? How many ccm? What RPM?
Do you think the flywheels are unbalanced? I guess, the whole engine is not balanced. Do you have counterweights on the crank?
I have a 87ccm 4 stroke that had no counterweights on the crank (in the plan) and it was nearly smashing the table when running. After calculating the propper counterweight and discovering that I have not enough room, I put the max possible to the crank. BIG difference!
Nick
It's a 6 horsepower motor, weighs about 600 pounds. Stand about chest high at it's high point.
Here's some pictures of a Lister clone I found on the web:
I don't think there are counterweights on the crank. My engine was a poorly designed and built Indian (from India) product. I believe balancing these huge flywheels will significantly reduce the floor hopping to manageable levels.
If I were to bolt this down, I'd imagine the engine would fracture some major castings in a year of two. The vibration is really that bad....
Thanks. Bigger than I thought.
Ooops!
Think you can't access the crank, nor want to access it. :-)
The math behind balancing is very easy: Rotating masses need a counterweight of 100%. Rotating is -for example- the crank pin, the rotating part of the rod*) ... Translational masses are counterweighted by about 50% (40..70%, doesn't matter that much). Translational is mostly the piston, it's pin and the other part of the rod. Each mass is multiplied with it's CG's distance from the crank axis. Translational masses with half the stroke. Add all values and remove or add that amount on the flywheel (divided by the distance).
*) Put the rod with the lower end on a scale. That weight is the rotating mass. The upper end gives the translational mass.Nick
There's a big access plate about 6 inches square you can remove to look at the crank/rod/underside of piston. It's been awhile since I've been in there tho.
This diesel engine rotates about 600 RPM or so.
You are so far above me it's not funny. I think I'm gonna have to take this entire engine down to a machine shop and let the pros take a look. I sure appreciate your input - I'm just not smart enough to make practical use of it.
Justion
Try reading
Eric Stevens
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