Crankshaft Counterweights

[Synchro909]

I have an original crankshaft on which the journals have never been ground. I'd like to use that in my next project and I'd also like to put counterweights on it. Does anybody have a dimensioned drawing for the counterweights that I could take along to a profile cutter to have them made? I would like the counterweights that have a ring that goes right around the boss on the shaft rather than the crescent shaped weights that are welded on
In addition, what is the feeling for adding yet more weight by attaching a kidney shaped weight to the side of the one mentioned above? That would give about double the counterweight. Is that too much or just getting closer to the ideal? I realise that would result in a greater "flywheel effect" because of the extra weight but that can be countered by removing some metal from the flywheel.
Here's hoping someone can help.

[Tanglfoot]

Hello Syncro99, I have counterweighted 12 cranks with what you call kidney shaped weights of varying weights to MA crankshafts over the last 10 years or so.One with weights purchased from Piranios in Texas all welded on. I have welded 10mm weights to the side of the 16mm weights, with no gain I removed them (10mm ones).
None of this gave me the smooth motor that I was expecting. I now have two model B dimond motors with the factory C crank and both are the smoothest motors I have driven so I will stick with them.
I have seen a MA counterweighted crank with some of the MA circle cut away to maybe balance the crank without adding weight to one side and say trimming from the jounal side. not sure if made any diff in the end.
I am convinced that adding weights to MA/B cranks only saves the wear on bearings.So could be worth while in the long run.

[Tom Wesenberg]

I bought the heavy full circle weights, like Ford used, and I bought them from a guy in Ohio. Now I need to find someone that can turn the crank to install them. This should be a great improvement for the life of the bearings, and possibly a smoother running engine.

[Kohnke Rebabbitting]

Originally Posted by Tanglfoot

Hello Syncro99, I have counterweighted 12 cranks with what you call kidney shaped weights of varying weights to MA crankshafts over the last 10 years or so.One with weights purchased from Piranios in Texas all welded on. I have welded 10mm weights to the side of the 16mm weights, with no gain I removed them (10mm ones).
None of this gave me the smooth motor that I was expecting. I now have two model B dimond motors with the factory C crank and both are the smoothest motors I have driven so I will stick with them.
I have seen a MA counterweighted crank with some of the MA circle cut away to maybe balance the crank without adding weight to one side and say trimming from the jounal side. not sure if made any diff in the end.
I am convinced that adding weights to MA/B cranks only saves the wear on bearings.So could be worth while in the long run.

Your right, Mr. Tanglfoot. The Ford weights are the best. Just welding a chunk of metal, sticking out one side of a crank, does very little. We started weighting cranks in the early 60's. We don't have time anymore, but we have about 150 of our weighted cranks in our engines. You can hold your hand on the head, and can't hardly tell it is running.


Here's a picture of one of our weighted cranks. They are 5/8's thick, and do not have the extra iron sticking in the way of the grinding, of Rod Pins.


The weights are shunk on, and Pinned, like Ford did it, they were NOT pressed on.


Herm.

[Synchro909]

Herm, Those are the type of weights I was talking about. I'll take on board what you and Tanglefoot have said about the extra weights although what I proposed doing was to have the extra weights removable so that they did not interfere with grinding. They would have been bolted and pinned to the other counterweight but if you say they are no gain, why suffer the pain?
Do you have a drawing of those weights - even a tracing?
Tanglefoot, I also have a diamond B engine and while it is smooth running, it does not have the power of my A engines. I didn't build it so I'm not sure what is in there. I suspect better breathing would work wonders on it.
I would have to use 16 mm plate to make them because imperial sizes have not been available here for decades. There is only a few thou difference between 16 mm and 5/8" which I would take off so there is no protrusion over the journal.

[Kurt in NJ]

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It was a long time ago but the V8 times had article about the counterweights, it also had the blueprint, shrink fit specs

[Pete]

Dan Price has the BB style weights.
[email protected]

[Synchro909]

Thanks Pete. I have just sent him a message from his website. I hope he responds and is not one of those businesses that never check their messages from their website.