Flywheel balancing question

[jeepdan]

The machine shop has boogered up my flywheel.
They got the NOS ring gear stuck halfway on. Then, tried to press it on the rest of the way, and went too far in a few places.

AB Linn still has several flywheels in stock.

My question is, will I have to send crank, flywheel, and clutch away to get things balanced.

The manual states that the crank and flywheel are balanced individually and as a unit.

[Don Cavey]

The machine shop has boogered up my flywheel.

...

The manual states that the crank and flywheel are balanced individually and as a unit.

That is a conflicting statement. If the parts are balanced individually, they should be able to be assembled without a need to balance the assembly again ... I would think.

[67smith]

unless known that the crank is neutrally balanced, the flywheel, front pulleys, crank and pressure plate should be balanced as a set(well, rods and pistons too)

that is the ideal way to do it, but you can cheap out and take the old flywheel and "match balance" it to the old one, but that is for the rare instance when the engine is all together

my suggestion is to find a good balance shop(any drag racers or short track guys around??) they should be able to tell you what you need to bring and what they can do to balance it

my guess is the manual means that the crank and flywheel are balanced individually for neutral balance and then balanced as a set to compensate for the additive offset balance...meaning if the crank and flywheel both have the acceptable unbalance and they are put together so the unbalance combines and creates a larger unbalance, you must correct that as a set(clear as a painted window right?!)

balancing ain't really a black art, but it does take some getting used too, to know how it all fits together

[md1970]

balancing only comes in to effect over 5k rpms. get the one from ab linn,bolt it on and go. you,ll be fine.

[Don Cavey]

balancing only comes in to effect over 5k rpms. get the one from ab linn,bolt it on and go. you,ll be fine.

I would say that is good advice. Not talking high performance with maximum revs...

[67smith]

balancing only comes in to effect over 5k rpms. get the one from ab linn,bolt it on and go. you,ll be fine.

incorrect, balancing is needed for any engine at any speed, it is how much balancing that is needed that varies with engine speed, most factory cranks come with a certain degree of balance "built" in there is no "need" to improve that

balancing an engine more then it needs increases engine life as it will not "wallow" around in the bearings- it can also decrease engine vibrations

this is also why pistons normally come in a weight set-any set of pistons lie within a certain "acceptable" range-normally within 10 grams for factory cars, 5 grams for performance, and 0-1 grams for racing

as for just slapping on the flywheel, you should be fine, but it should only be about a $150 job to balance everything-well worth it when you've gone this far with everything-IMO

I've done several auto to manual transmission conversions, where match balancing plays a big part into reducing vibrations(which tended to decrease engine life)

[jeepdan]

The flywheel came from ABLinn, and it's not usable as it is.
The ring gear isn't seated properly and the flange is broken.
ABLinn apologized and immediately refunded everything.
But, they haven't answered my request yet, asking them to sort through the pile, to find a good one.

I see that the one they had on ebay disappeared at that time also.
Don't know if they pulled it, or someone bought it.



So, I'm revisiting the original flywheel.
For free, The machine shop has got the ring gear positioned on straight They had to machine off the broken flange that the gear rests against, and then put a few tack welds on.
But, they machined off the 10 1/4" dia. step on the flywheel face when they resurfaced it.
The step is only .005" high, hope it doesn't matter:

[md1970]

IF they didnt heat the flywheel correctly "before" welding it it will not hold. the weld will crack . cast iron is very finicky to weld. then immediatly after welding it has to go back in the oven and be stableized then cooled very slowly. i,d also have them chuck it up in a lathe and use a dial indicator to make sure the starter ring is straight.

[skyj]

Jeepdan, if you don't come up with anything I have a NOS in the garage. Cover the shipping and what I have in it (I think 25$) and it's yours. Jim

[jeepdan]

Jeepdan, if you don't come up with anything I have a NOS in the garage. Cover the shipping and what I have in it (I think 25$) and it's yours. Jim

Thanks Jim, I really appreciate that. PM sent.