Harmonic Balancer

[85CUCVtom]

I got a question. Is it absolutely necessary to replace the square key when replacing the balancer?

 

[Dave Kay]

I got a question. Is it absolutely necessary to replace the square key when replacing the balancer?

I didn't, just re-used the old one and after 10K miles I've had no problems.

 

[ixpacman]

I still don't know why my key sheeted and allowed the balancer to spin but for what the key was worth I replaced it with new one on the replacement engine. Probably would hurt but doubt it is a huge issue. Destroying a perfectly good engine that I took good care of hurt my feelings.
Harry

 

[MarcusOReallyus]

I got a question. Is it absolutely necessary to replace the square key when replacing the balancer?

To answer that question, ask two more:

1. How much is a key?
2. How much is an engine?

Yes, finding the right key might take a bit of work.

How much work is it to replace an engine? (Oh, and you'll probably need to find a new key, too.)

 

[Keith_J]

If the key looks damaged, replace. But if it looks fine, don't bother. The key is security, the press fit should be enough to retain it. Since press fits are on the order of 0.0005", machining tolerances may stack up to make for a looser fit. The key is also a designed failure point, just in case something freezes on the accessory drive system. Much like a power steering pump, only this device doesn't have a key because it isn't timed.

 

[85CUCVtom]

Awesome, those were the kind of answers I was looking for.

I'm gonna get a new key before I do this project. I'll post up my results on tracking down a key.

 

[lonewolf90]

Question I notice that my crank pully is wobbling after I did a oil change and a fuel filter change. Do you have to drain the oil to change the front seal

 

[Warthog]

No

 

[doghead]

Key, 106751

google it.

 

[85CUCVtom]

Thanks DH. I was gonna look up the number in the TM when I got home from work. Of course I forgot about it.
Then I saw your post and thought to myself, "I forgot to look the number up in the TM".

 

[85CUCVtom]

So I was able to locate the keys at a couple Chevy dealerships within 2 hours of my house. I'm really not wanting to drive that far for an $0.85 part and I would like to have it by the weekend.

Does anybody see any reason why I couldn't use a key from a hardware store? Provided it was the same size and thickness. Were the original ones hardened or special in anyway?

 

[85CUCVtom]

Anybody?

 

[Warthog]

Wonder if they would mail them to you.

 

[85CUCVtom]

Yes they would. I was trying to get this project down this weekend. A local hardware store has woodruff keys the same size. If I could get it from them, provided they are the same, it would be great.

 

[T. Highway]

I would make sure what kind of material the keys at the hardware store are made of.

A plain steel key will not be rated for hardness and the vibration of the damper will peen the key in short order, causing a spin failure.

A SAE No 8630 alloy steel key is better suited for the application. This would have a better strength and toughness for the damper vibration.

I hope this helps,

Bert

 

[85CUCVtom]

Yeah it does help. Thanks. That's the part I was concerned about.

I did speak to the guy at the hardware store. He said the ones he had were mild steel. Not hardened or heat treated or anything. Suitable for use on say an electric motor. I'm not gonna risk it.

It looks like I'm gonna have to wait and order the correct ones.

 

[lonewolf90]

I bought my harmonic balancer at Autozone and it came with a new key. Wounder why yours did not

 

[85CUCVtom]

I was surprised too, seeing as it was an ACDelco part.

 

[85CUCVtom]

I finally received the Woodruff keys from the Chevy dealership. The guy was really nice and didn't even charge me postage. Harmonic balancer time this weekend!

 

[lonewolf90]

Anybody have any insight on how to stop the motor from turning over so I can get the pulley and balancer bolt off thank you