internal vs external engine balancing question
Thread Starter
Burning Brakes
Joined: Aug 2000
Posts: 1,211
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internal vs external engine balancing question
When the machine shop balances the rotating assembly using "bob weights" does the external balance include the flywheel and dampner weight? And, conversely, with the internal balance would they not include those weights as they are neutral balanced or do they include them as well?
Thanks, Mark
Thanks, Mark
Drifting
Joined: Oct 2000
Posts: 1,825
Likes: 56
From: Shawano WI
Re: internal vs external engine balancing question (marky mark)
When the machine shop balances the rotating assembly using "bob weights" does the external balance include the flywheel and dampner weight? And, conversely, with the internal balance would they not include those weights as they are neutral balanced or do they include them as well?
Thanks, Mark
Thanks, Mark
To give you a simpliler comparison would be if you had a wheel that was perfectly balanced and a tire that was 2 oz out of balance and you put them together you would use a 2oz wheel weight to correct them regardless of the weight of the entire assy.
Balancing a crankshaft is a lot more complicated than that as every engine builder will use a slightly different correction factor to simulate the big end of the rod and the weight of the oil hanging on the rotating assy but I think that is what you were reffering to in your question.
Thread Starter
Burning Brakes
Joined: Aug 2000
Posts: 1,211
Likes: 6
Re: internal vs external engine balancing question (Pete79L82)
Yes Pete, thanks for the answer.
But how do they measure something as neutral (such as a flywheel or harmonic balancer for an internally balance engine)?
But how do they measure something as neutral (such as a flywheel or harmonic balancer for an internally balance engine)?
Drifting
Joined: Oct 2000
Posts: 1,825
Likes: 56
From: Shawano WI
Re: internal vs external engine balancing question (marky mark)
Yes Pete, thanks for the answer.
But how do they measure something as neutral (such as a flywheel or harmonic balancer for an internally balance engine)?
But how do they measure something as neutral (such as a flywheel or harmonic balancer for an internally balance engine)?
On an internally balanced assy, you first balance just the crankshaft, then put on the balancer and recheck the assy for balance and it should not change. You then do the same procedeur for the flywheel.
On an externally balanced assy they are all balalanced at the same time as one assy.
Pete
