[mchell]

Got a quick question:

I think my balancer has slipped.

When looking at a Pontiac harmonic balancer key way. What is the corresponding timing degree in relation to the key way?

Don’t have another one laying around to compare,.

Thanks

[lust4speed]

Just happen to have a pic from yesterday. Using the 2A slots, but that's only two degrees off and would be tough to eyeball the difference. Which brings up another point is the damper might only have slipped a few degrees which would be near impossible to discern.

[dataway]

If it's still on the engine ... use the #1 plug hole to find TDC and check it against the timing marks.

[mchell]

Originally Posted by dataway

If it's still on the engine ... use the #1 plug hole to find TDC and check it against the timing marks.

Did that first thing...it appears to be off 20 degrees or so

Still like to see where the balancer key way slot is in degrees. That would verify my findings.

I did order a new balancer (dayco power bond Sfi from Butler),

Thanks

[mchell]

For those that have a good balancer laying around:

At what degree is your balancer key way clocked to?... 100 degrees, 140 degrees etc.

Your balancer will have to have some marks all the way around to give an estimate of where the key way is normally clocked.

Trying to get a reference on a good one. Sounds like it’s not going to be possible without having a good one right next to mine.

I”m confidant that mine has slipped. Just looking while waiting for new.



Thanks

[johnta1]

Did that first thing...it appears to be off 20 degrees or so

When the engine is at TDC on #1, where is the timing mark on the balancer compared to timing cover?
Clockwise or counterclockwise from the timing cover mark?

[mchell]

Originally Posted by johnta1

When the engine is at TDC on #1, where is the timing mark on the balancer compared to timing cover?
Clockwise or counterclockwise from the timing cover mark?

Counter clockwise....see the pic I just posted

Thanks

[TedRamAirII]

With a new balancer, mark the hub and ring, so you can keep an eye on them and catch any obvious slippage.

[Lee]

Originally Posted by TedRamAirII

With a new balancer, mark the hub and ring, so you can keep an eye on them and catch any obvious slippage.

I use a chisel, to make reference marks on the outer and inner.

I also now make a paint mark on the crank pulley, inline with the timing mark. Then, when checking timing, I can see if there has been slippage.

[Schurkey]

Originally Posted by 1969400HO

My experiences, If TC (cam & crank) is at Zero with No Adv-Ret, offsets, the (installed on snout) damper should then display the “Zero” groove-line mark at the TC-Cover’s pointer-finger line / edge.

The timing chain advance/retard has NO bearing on the TDC mark of the torsional damper lining up with the TDC mark of the timing pointer. TDC #1 is TDC #1, no matter where the cam is positioned.

Originally Posted by Lee

I use a chisel, to make reference marks on the outer and inner

Best to avoid the (sharp) chisel, as the sharp indentation makes a perfect stress-riser potentially leading to a crack.

I've put marks in dampers using a center-punch; but then I set a small ball-bearing on the punchmark and whack it with a hammer to create a rounded impression with surface compaction, to avoid cracking.

[Lee]

Originally Posted by Schurkey

The timing chain advance/retard has NO bearing on the TDC mark of the torsional damper lining up with the TDC mark of the timing pointer. TDC #1 is TDC #1, no matter where the cam is positioned.

Best to avoid the (sharp) chisel, as the sharp indentation makes a perfect stress-riser potentially leading to a crack.

I've put marks in dampers using a center-punch; but then I set a small ball-bearing on the punchmark and whack it with a hammer to create a rounded impression with surface compaction, to avoid cracking.

Not like it is a crank gear, no real stresses on THAT part of damper. Being doing that for over 20 years without an issue. Doesn't need to be deep, just enough to make it obvious.

[mchell]

Current situation:
See pic

With Engine at TDC on # 1....note that “zero “ on the balancer is now retarded about 20 degrees

While checking my timing I noticed it was advanced off the chart...dist was not loose, pulled dist and double checked everything and it was ok. Tried adjusting timing but it was wanting me to retard so much that I knew something was wrong as I kept having to idle it up way beyond normal.

That’s what led me to the balancer.

Never had one slip like this.

[mchell]

Also,

The uploaded pic looks crappy....try this one

https://share.icloud.com/photos/09gI...aQw#North_Port

If your looking at the pic the white line(on the balancer) is 34 degrees NOT TDC....I use that to reference my total quickly. The white line (kind of hard to see as it’s shaded)on the timing cover is zero.

[mchell]

Anyways,

Sorry for the confusion......every balancer should have the key way clocked at X degrees so the balancer timing marks reference the timing cover marks close enough to get timing.

I was trying a secondary verification by having someone look at a good one that is not on the engine.

My key way right now is clocked to about 100 degrees....should be about 80?

[johnta1]

Yes, it looks like it has slipped if the crank is at TDC.
It would be retarded.


What brand of balancer is that?

[mchell]

Originally Posted by johnta1

Yes, it looks like it has slipped if the crank is at TDC.
It would be retarded.


What brand of balancer is that?

Had this one for 10yrs ...can’t remember what brand...pioneer? Sfi two piece with the locking ring.


It’s marked with a “PB” brand.

[1969400HO]

Interesting thread here.
My experiences, If TC (cam & crank) is at Zero with No Adv-Ret, offsets, the (installed on snout) damper should then display the “Zero” groove-line mark at the TC-Cover’s pointer-finger line / edge.

I’ve seen where the cover finger was wrong and or the damper was wrong also, at OEM instal of all parts.

It was a matter of figuring and get the proper pieces to make it sync-align, else would so cause confusion.
It all should align rather simply as designed!! (in a perfect I dream of Genie show world).

Work around I also seen is the inner mechanics of TC setting once you Do have this TC set, then THAT is the bottom line!!

You will need to make the damper its “new Zero” TDC mark.
Which is cosmetically Wrong yet the engine doesn’t care!
Just make your new Zero line mark, on the damper, like a Butler damper tape placement on it etc.

And finish the task or go gather the correct TC cover or/and damper combo pieces..

And Yes these old damper have old rubber inserts Do have a limited life span, I had one on my Honda accord spin slightly on me causing a lot of havoc & days of troubleshooting my electrical system. (poor battery charging issues-next morning No starting)

Hope this helps.

-------------------------
Don’t fall for the banana in the tailpipe!!

[firechicken]

Powerbond perhaps

[mchell]

Well....should have removed pulley before I posted

See pic....definitely spun

Look at the fresh shiny spots...

https://share.icloud.com/photos/0ww5...NZbYJ1OtlnwVjg

[johnta1]

Well, good you found it before it exploded!