Ok so I used to have major idle problems with my 89. Replaced a lot of parts and reset the idle many many times...

What fixed it was when I adjusted the idle. Weird thing was everyone said I was supposed to use the timing light to set it at 8 degrees on the timing marker. I unplugged the computer wire and it was already set to 8 degrees. So I moved it around and found my car runs perfect at 0 degrees. I don't understand how the car could of run so bad at factory spec of 8 degrees.

So I was wondering if it was possible the marker itself could of been moved or something accounting for the difference in degrees....

Been running the car now for months like this and it works great... could I be hurting anything?

 

The outer ring could slip on the balancer. You could bring #1 to top dead center to verify this.

 

Jack Didley knows Jack Didley!

 

Not unusual with age

 

The bad part is, I'm pretty sure mine looks like that. Last time I had it off was 65000 miles ago and it didnt look too good then.

 

Good to know. I was actually referring to the piece of metal with the numbers on it. Can that piece of metal with the numbers on it move, not just the pull itself?

 

Not likely. If the ring slips, the effect would be the same.

 

The scan only reports the advance as it programmed in the chip. It has no way to know the actual position of the distributor.

 

Hence the reason for pulling the "dist" wire when setting base timing.

Mustang_Eater, you can fabricate a simple TDC finder from an old spark plug and a bolt. If your interested I'll post the steps or look for one in Summit or Jegs

 

Yes if you wouldn't mind. I decided I would like to make sure my timing is correct and if the bearing wore I don't know how to check....

 

Gee they are 6 degrees apart go figure. Ok so how in the world would the ecm know where tdc is.. I will help you it does not know...
Dave

 

So is there a definitive way to check the timing without a timing light.... besides listening to the engine while you rotate the dist cap? (As the outer ring has most likely slipped on the balancer)

 

No because the timing tab is fixed solid to the cover. The center hub part of the balancer is metal and secured to the crank one way by the woodruff key. This part can never shift or move unless the crank groove holding the key shears. There is a piece of rubber sandwiched between this hub and the black outer ring with the timing line on it. It's the one that's all chewed up in the above picture. When this bond fails the outer ring spins moving the timing mark with it and begins to walk back towards the timing cover.

Indentifying Balancer Slippage:

There is a hole in the metal timing tab of the timing cover. I don't know what it's for but one way to identify a slipped balancer still on the car is if you can see any part of the balancer through that hole from above. If you can then the balancer outer ring has slipped and has walked back closer to the timing cover and your timing mark is now out of place. There should be about a good inch of space between the back of the balancer and timing cover and you should not be able to see any part of the balancer though that hole from above.

Another way is also by using the metal timing tab on the timing cover. On a good balancer the pointed tips of the tab will hover about halfway over the width of the balancer ring. This is shown in the first picture below with the Blue line. Red line shows outer ring flush with center metal hub. This is a good balancer.


Second pic down shows slippage with Green arrows. Outer ring and hub are also no longer flush as a direct result (Red line). Balancer has backed up all the way against the timing cover and is rubbing. The pointed tips of the timing tab are no longer hovering above the halfway point of the balancer ring's width (Blue arrow). Another tell tale sign and hint of balancer slippage.

Good Balancer:



Slipped Balancer:



No. The bottom line is until you replace the balancer with a new one you're not going to be able to set your timing dead on with your light. The good news is that the new balancer is only $55 at Autozone and tool rental is basically free. A slipped balancer can begin to grind against the timing cover and make a hole in it. When that happens you'll not only have a big azz oil leak but metal shavings will be tossed into your motor oil at the same time. So you might as well break down with the $50 now and replace it before it's too late and not put this off.

I've seen balancers that are already rubbing up against the timing cover that go unheard and unnoticed by the owner's inexperienced eye. Also because the engine running drowns out the grinding noise it's making against the timing cover.

Use a balancer puller and installer tool (two separate tools). You can rent both tools with a refundable deposit at Autozone. Don't be an idiot and try to press your new balancer on the crank using only your crank bolt. Don't try to beat the new one on either or pry the old one off cause it ain't going to happen. Use the dedicated puller and installer from Autozone to remove the old and install the new the right way.

Crank Bolt:

To keep the engine from spinning while you break the crank bolt loose put the car in high gear if you have a manual trans. Also set the parking brake and chock the wheels.

On an automatic like mine what I did was remove the flywheel cover. Then I put a long (I think 15mm) Snap-On wrench on one of the torque converter bolts and let it wedge itself against the exhaust pipe. Craftsman wrench was too short to reach. This kept the engine from turning while I broke the crank bolt loose. When re-tightening the crank bolt I placed the wrench on the bottom of the pipe instead of over it to hold the engine from turning the other way. It worked great and never felt unsteady or like it was going to slip. It held rock solid.





Here's my old vs new with the woodruff key slots lined up. Notice how far off my timing mark had moved.










Balancer Removal and Installation:

You need the balancer puller part#27019




And the balancer installer part #27144




Here is how to remove and install the balancer step by step with these two tools.

Removal:



Installation:



NOTE: The removal and install process is exactly the same only you're going to be doing it inside the TPI engine bay with less clerance. Because of this use a deep socket over the end of the puller to turn it and not a shallow socket when pulling the old balancer off. This is because the tool will be right up against the top steering rack line. The deep socket act as a protective cup and shields the puller's threaded shaft as it turns preventing galling and damage to the threads. This way the puller doesn't rub directly on the steering line. Instead the socket will rub but not the tool.

If you have to just go ahead and loosen the top steering rack line and move it to the side for more room. There is no o-ring on this connection so don't worry about loosing it.

 

No.

 

Thats scary to see that considering how fast that thing is spinning!

 

I'd recommend putting sealant on the woodruff key slot of the balancer before you put it on.

 

Another way to find tdc is look at the crank key w/ a mirror, should be halfway between 12 & 3 o'clock. If the timing marks are not close, then the balancer has slipped.

 

Wow thanks for the info 86pacer.

Below is a picture of my balancer... it does not look like there is any slippage....

Can someone please confirm what degree the timing should be at on a 89 Corvette? Maybe it's not supposed to be 8 and I just need to set it to the correct degree.

My idle issue went away as soon as I put the timing to 0 degrees so I know that 8 degrees doens't work on my car when set with the timing light.



Uploaded with ImageShack.us

 

Supposed to be 6 degrees.

 

Thanks! I'll give it a shot and see if my car dies at idle as it did at 8 degrees.