Crankshaft pulley wobbling (2006 Silverado 1500 v6 4.3L)

[goldentv]

For the past few weeks I've been trying to fix the wobbling of my crankshaft pulley and balancer. When I turn the truck on it automatically starts shaking much more than normal. The crankshaft pulley also wobbles. I've replaced the balancer, and then the crankshaft pulley. Still wobbling. I then took off this little piece of like silicon / caulk that looks like someone tried extending the key, a bit. Still wobbled. I have no idea, I really don't think its the crankshaft bolt. I torqued everything down right, I have no ****ing idea. Can't take it to a mechanic either.

 

Anyone else have this problem? How the hell do I fix it?

 

Edit: This happened to me when I was pulling out of my drive which is quite bumpy.

 

Edited July 15, 2019 by goldentv

[Jglew82]

Do you have a dial indicator? If not, borrow or buy one. Take off the balancer and pulley and check if the crank snout is bent. 

[goldentv]

Aren't those only needed with certain engines? My balancer just slides right on so I don't think I need to set it.

[riverbanks]

He's not talking about setting it,but where the problem is,yikes,was the original loose for so long,it ruined the crankshaft?

[txab]

I've seen this before. Then the end of the crank snapped off. As noted above check bare crank surface and check for it running out of round.

 

Did you try running it without the pulley and just watching the balancer/crank rotate?

 

A bumpy driveway doesn't cause this, imo

Edited July 16, 2019 by txab

[goldentv]

No I haven't tried it without the pulley yet, I can today. As soon as the problem came up I stopped driving it and only started it to test it.

 

And riverbank it was very sudden. I was turning my wheel to the edge for a 2-point turn and then I noticed it wouldn't go all the way back without some effort. It was very sudden. I did notice a whirring noise when turning my wheel all the way to one side since I got the truck (craigslist).

[goldentv]

Update: I just turned it on with just the balancer on, it was definitely not as bumpy at all really. But I did still notice it was wobbling a bit.

[Jglew82]

Remove everything in front of the cover to where JUST the crankshaft snout is exposed. Check runout with a dial indicator. This will tell you if your crank is bent. You need to do this to find the issue. Here's a visual reference for what you need to look at (ignore the specific crank, this is just an example) install the indicator to the snout, zero it out, rotate the crank BY HAND and watch the gauge, if the needle jumps around as it spins, it's bent. 

 

 

Edited July 16, 2019 by Jglew82

[goldentv]

And if it bends, I'm guessing im ****ed

[riverbanks]

The mention of the caulk in 1st post,sounds like a problem from long ago,like someone left the bolt loose,tried curing the problem with a "filler"

[riverbanks]

Search for epoxies,like Devcon, maybe worth a shot,and the binding steering?get that fixed,too much strain

[Jglew82]

2 hours ago, goldentv said:

And if it bends, I'm guessing im ****ed

If it's bent, then the crank is bent. Not the end of the world, but the engine will need to come out. 

 

I'm still trying to wrap my head around how all this is related to your driveway.. Do you think you could have smacked the pulley on your driveway/curb/a big ass rock somehow? Not likely, but maybe if you are able to post some pictures or a video of what's going on, that might help. 

[riverbanks]

Maybe not bent? someone left key out after a repair and balancer spun?sounds like a dishonest seller

[goldentv]

Here's the silicon / epoxy that was on it. Someone told me to remove it.

[riverbanks]

I would remove it,got to see what's up,so broken,wrong key?and are you sure bolt is not bottoming out?before balancer is tight?