Balancer boy (Long)

[Katoom]

Lucky me!

A few years ago I was doing an oil change on the cat. I noticed a knocking sound a couple of days prior to. While up on my friends hoist, I asked him what he thought it might be. He said to take the belts off and run the car to see if it went away. If it did then it was some sort of accesory. If it did not then (gulp) major problems existed.

I never made it that far. Once I got the belts off, I felt that the crank pully was loose on the balancer! I pulled each bolt head out with my fingers, they were all rotted.

I removed the balacer, drilled down through each bolt and used the straight style Snap-On extractors to get the bolt remains out. A trip down to J&E bearing yielded new allen head grade 8 cap screws. That was 5 years ago.

Now, after learing so much about balancers from this site, my next dillema has been solved, at least for the time being.

I observed a wobble in my crank pulley last fall. I stored the car this winter and just never got around to it.
I know that the pulley/balancer come as a balanced kit, but to see if maybe the pulley was bent from the escapade 5 years ago, I took the pulley off my parts car and swapped it to the XR-7. Same wobble! (Uh-oh)

I took the balancer off the parts car and observed that the pulley bolts were not Ford originals. Closer inspection revealed that two of the four holes were kinda stripped. (D'oh, same problem as mine)

Some guy showed up inquiring about parts off my bird. He needed help getting his newly installed motor running, so I took a trip down there only to find he had two other motors there, both with good balancers, original crank pulley bolts.

He gave me one for helping him get his car running.

Now the tricky part. The Xr-7's original pulley had a balancing weight on it. The pulley on the good balancer did not, but it's pulley was really rusty (rotten), so I didn't want to use that. The pulley on the parts car was somewhere in between the two, and had no weights on it.
So...the good balancer from buddy was installed with my parts car pulley!

I quickly realized from looking at three assemblies at the same time that the notch on the back side of the pulley should go just to the right of the large groove in the side of the balancer. If you look at the mounting flanges of the balancer, you will notice that the holes are not centered. The almost make up a pattern and the all seem to have come off the same machine. They all lined up perfect.
Some balancers have pins and holes drilled to balance them, Some pullies have weights tacked on the inner ring of the large pulley to compensate if balacner drilling and pins could not get all the wobble out.
Lucky for me, the parts car pulley and the really rusty one had no weights. I know it won't be perfect, but how much can a pulley be out? I think this is a safer bet than leaving ol rolly-polly on there.

Anyway, the combobulation of the two assemblies was installed on the car tonight and works perfect. You can't even feel the motor running at all now and it's visible to the eye that there is no more balancer or pulley wobble. This thing is running straight and true now.
My Ford dealer has the tougher washer and bolt ordered for me, hopefully it will be here soon.
This winter I will try and pop for brand new assembly...maybe even a BHJ.

[Paul93SC]

This Harmonic Damper/Pulley issue has been debated a lot in the past, and in the early years much of the information was... well... wrong.Some pulleys have weights tacked on the inner ring of the large pulley to compensate if balancer drilling and pins could not get all the wobble out.This isn't right. The steel crank pulleys are all neutral balanced by themselves, and may or may not have weights added on. This is why you can simply bolt on UnderDrives and go (all U/Ds are neutral balanced).

Ford used those balance pins in the harmonic damper during assembly & testing in order to balance the complete crankshaft rotating assembly. When replacing the damper, their advice is to swap the old pins into the new balancer, and in the same position(s) they were on the old one.

I would assume this advice is useless to someone who has had their engine rebuilt with new parts because the whole thing would require re-testing and re-balancing; something I've never heard anyone do. It might not be an issue due to the fact rebuilds are better balanced than production line engines were... but this is just speculation. I do know when mine was rebuilt they removed all the balance pins from the damper.The almost make up a pattern and the all seem to have come off the same machine. They all lined up perfect.You can only install the pulley in one position on the damper... the 4 holes are not equal distance from the centerline. I imagine they did this so that the timing mark (groove) on the crank pulley would line up properly with the timing index scale.

For more information on this, contact Duffy on the TBSCEC... he's the one who set us straight on the whole issue.

[Katoom]

Thanks for the info. I have a slight engine shake at 1100rpm now, yet the balancer and pulley are running straight and true. The original balancer had one pin. I think I will remove it and install it in the balancer that is on the car now. That might fix it. As well, my pulley was by far thes best one of the three.