Guys: I think i may have a slipping balancer. I am getting pinging when revving the engine after re-setting the timing. I had to do this recently when I put new plug wires on. The rotor was 180* off and the plug wires were a mess. Anyway, all is well with the wires and rotor, but I am struggling with timing. The car fired immediately and ran well just off my reference marks I made when pulling the distributor. Anyway, it runs more roughly/slowly as I advance it to 6 BTDC. It ran smoothly/faster at an indicated zero degrees on the timing mark. Due to the direction of balancer rotation, I assume the slipping (if that's what is happening) would produce a too-much advanced scenario even if it showed only a few degrees of advance.

So how do you time it by ear? (Yes I will replace the balancer!) Do you just get it to where it's smooth and happy? Ideas please!

 

you could use a vacum gage, set it to highest vacum and then back it off a bit, if your rpms 'hang' you've gone to far

 

I read elsewhere that you could do this. Reach maximum vacuum and then back off a degree or so (best estimate you can make, I guess). I have a vac guage on a mityvac and I think that will work.

 

You dont!!

Get yourself a timing light and do it right unless youre the car whisperer.

 

Definite do not set the the base timing by ear on any EFI equipped car.

Timing light right way as Ron said..

 

If I read the op post right, he is using a timing light. First, did you disconnect the tan/black wire that is just under the brake booster before putting the light on it? This has to be done to get an accurate reading on the light. Try setting the timing with this wire disconnected first. I think you will find that all is good. Don't forget to re-connect the wire after you're done. If you still have a problem pull the plug out of #1 cylinder and bring the piston up to tdc, put a finger over the plug hole and turn the engine a bit at a time until you feel compression pushing your finger off the hole. Stop as soon as you feel pressure then turn the engine by hand while using a small screwdriver placed in the hole to feel the piston as it rises to the top, once you are at the top, check your timing marks to see how they are lined up. This is as close as you're gonna get to true tdc with out seeing the marks on the timing chain. See where the timing marks are, that will tell you if the balancer has in fact slipped. If they are lined up properly then set the timing as I described above, disconnecting the tan/black wire first.

 

The vision of that !

 

he suspects his balancer counter weight is slipping on the hub, timing light wont work, even though he has one

 

Verify the slipping harmonica balancer with a piston stop and a scribe. If it is off make a new TDC mark. If it's not....find the problem. Get some timing tape to show your timing marks and time it to specs.

 

Thanks to some for reading the initial post. Pretty sure I nailed the distributor when I set it because the car fired immediately and ran faster as I advanced it a few degrees. But when I set to 6* BTDC, I get detonation when I rev the car. That proves my timing marks are off. I guesstimate maybe 10-15 degrees off. I was just hoping someone might tell me to just find the smoothest idle point and lock it down. If so, do I do that without the ignition wire connected (I am betting I do)? Do I do it warm? Do I do it cold? Is the smoothest idle where I will generally be fine with a bit of advance or will it be right at zero? Just give me some basic ideas. I am thinking I'll set up a pointer on dist cap and mark the extremes for advance and retard and then find the center spot between those marks. Hopefully, that will jive with the smooth spot???

 

What you're going to attempt is not going to work well. It seems like you want to do it so go ahead and try. You may get lucky. If it works like it should then rush out and buy one lottery ticket. That's all you'll need to hit the big one.

 

Please re-read my post, I explained how to get a ballpark idea of true tdc. If you are determined to run the car without knowing where the timing really is then you must also be ready to accept the possible problems.

 

If you "think" it is the balancer I would better diagnose it before replacing it. First, try a different timing light, I had a timing light that went bad once that threw my setting way off. As already mentioned, do the TDC test with a piston stop and scribe, this is the most precise and best way to find TDC with the heads on. If it is a slipping harmonic balancer, once they start slipping they keep slipping and your engine's external balance is now off, replace it soon.

 

Just because it is knocking, does not mean your balancer has slipped. You may have a problem with the ESC or knock sensor and/or wiring between these components. Do the TDC check with the mark on the balancer. It is very easy to do. Then set the timing with the wire unhooked (warm). Even easier. If it is still knocking, time for some more troubleshooting. First stop...knock sensor connection.

 

If your balancer has slipped and you aren't going to replace it (for whatever reason), set the timing back where it was pinging, retard the timing 2 degrees and test drive. Keep doing this until the pinging goes away, then retard another 2 degrees and you should be pretty close to where you need to be.

 

SBC harmonic balancer that have the cast iron outer inertia ring with timing marks that slip on the center hub have been known to come apart at high RPM's.

When they explode apart from the center rubber bond letting go.
The balancer will either hit the ground or go through the hood of your Corvette.

Like a small bomb going off.
Not as bad as a flywheel & clutch explosion that cuts off you legs, feet, & decapitates you,
Just a big hole in the hood at the worst.

 

they eat water pumps also

 

And if they do come off, first they make a big banging noise that makes you wear out your BVD's in a few seconds and when they hit the ground they can turn 90 degrees, accelerate past your car and it will be well in front of you, spinning wildly trying to get traction heading for the side of the road as you pass it. You will be confused and wonder what the heck it was for a few minutes. Go ahead, ask me how I know

 

I did similar too back in 1998 on my 1963 Grand Prix with a 1973 455 topped off with a 1965 GTO manual trans Tripower.
Turbo 400 trans from a 1976 Grand Prix.
3.23 Posi tracation rear.

Racing my buddy Mopar Bob home on a Friday from work.
Both worked in the same machine shop together back then.
He drove a 1995 or 1996 Dodge Daytona VNT turbo 5- speed.
His car ran good too.

Running south on I-39 around 100mph neck to neck.
I floored the gas before he could downshift to 4th gear.
Wrapped the speedometer full right on my 63 way past 120mph.
Tach was reading 6,500 RPMs or so.
Heard a giant bang & then the powersteering & brakes were gone & alternator red idiot light came on.
Engine kept running.
I seen a shower of sparks about 100 feet forward of me dancing around on the highway 4 or 5 feet off the ground..........
Then it seemed to Accelerate back torwards me.
Went underneath my car and banged around somewhere.
Looked in the rearview mirror..............
Mopar Bob was right behind me....................
Thought I was going to kill my buddie with the flying shrapnel.....
Watching in the mirror it missed him and went in the ditch.

We both stopped & looked at each other with a cold stare & then started laughing.
Opened the hood on my old GP.
The harmonic balacncer was still intact.
But the lower drive pulley had sheared right off the 4 mounting bolts.
Bolts still tight.
Sheet metal pulley had let go.

I know exactly what you were thinking too when similar happened...........oh CHIT>>>>>>>>>>>

My bud BOB said the same I am sure.

Brian

 

I am a full pledge believer in SFI approved harmonic balancers, Billet steel, or billet aluminum crankshaft pulleys also now.

Even on the street playing hard.