2F neutrally balanced? (balancing the rotating assembly)

[CruiserShel]

I am rebuilding a 2F and asked the machine shop to balance the rotating assembly. They said that unless it is "neutrally balanced" they would need the harmonic balancer and flywheel to do it right. Is that necessary?

The reason I need to know is that this is a donor transplant motor that the machine shop has. I haven't removed my old motor yet, so I don't have the flywheel or balancer handy, so it will delay the whole timeline if I have to removed them before he can do the machine work.

Can he balance it without the harmonic balancer and flywheel or do I need to get those to him to do this right?

Does anyone know if the 2F is "neutrally balanced"?

 

[LAMBCRUSHER]

typically a balance would include the balancer and flywheel, piston/rod floating assemblies and crank.

 

[LAMBCRUSHER]

as much of a hassle as it is, just be patient; this is not the place to get rushed...

 

[shaneus]

I am not sure about the 2F but many engines (like most ford V8's) are externally balanced. This means the dampener and flywheel both have weight built in at a certain point. Many other engines (i think most small block chevy's) are Internally balanced, these have dampeners and flywheels with no extra weight built in.

I believe the reason for external balance is not enough room in the crankcase for the extra weight lobes on the crankshaft.

Regardless - provide the machine shop the flywheel and dampener if your going to get balancing done. Also, have flywheel surface for new disc before hand. After balancing you will not want to make any changes. If dampener has old dried out rubber with lots of cracks it would be a good time for a new one.

 

[LAMBCRUSHER]

dampers can be sent in for revulcanizing. there is an outfit in WA state that does it, as well as SoCal IIRC. can't remember names, but they have been mentioned here and can be found on the webs...

 

[MoCoNative]

Take this with a grain of salt, I'm no pro. What I have seen on all F family engines is that the dampener and flywheel appear to be balanced by themselves. Each of those components has places where they are drilled out to reduce weight, to, I assume balance them somewhat. The crankshaft itself is pretty large and heavy and they too appear to have custom amounts of weight removed from the lobes to balance them.

None of these engines were ever really well balanced from the factory. The dampener and flywheels can only bolt on in one orientation, dictated by the woodruff key on the front and the dowel pin on the flywheel. I always assumed, any dampener and flywheel was pulled off the cart and bolted to the engines as they came down the line and the engine was internally balanced by the crank.

Can this all be improved on, of course, and if the shop had all the rotating assembly, I bet they could do a better job than not having it. But in the end, I have assumed that balancing the crank, and equalizing the weight of each piston and connecting rod assembly would net a pretty good balance on any F engine and some of that can be done at home for that matter.