Mario Mare

Hey guys.. new to this forum.

I have a 99 Buick Century, 3.1L engine, auto trans as one of my project and am having an issue with my harmonic balancer..
No, it's not Chevrolet but hey I'm a 3rd gen Camaro fanatic, plus I just couldn't get much inputs from other forums (including Buick forum) so I am hoping someone out here can help me out.

My backstory is this - car had engine light on calling for crankshaft position sensor.
First thing first I looked for the sensor to buy them, I don't know why this vehicle comes with 2 sensor under the same name.. one is magnetic tube looking by the block and other one looks more like a harness that attaches right behind the harmonic balancer. Didn't wanna waste time, so bought both of them, replaced both of them.

Now when I removed the harmonic balancer, changed the sensors and put everything back on, my car vibrates like crazy. Engine codes are all cleared however.
It got a little scary so I parked back the car right away. After a thorough research, my balancer may not be fully seated for some reason? but I used proper tool to push them back in as much as I could.. I felt like I was almost gonna break the tool, so I know it's pushed really good. Torque on the center bolt should be pretty good too since I used my impact gun rated up to 200lb, which is close enough to what the torque spec calls for.

I am attaching some pics for reference and my 2 questions are..

1. Is my harmonic balancer bad? I didn't have this vibration before this job so I don't think it's bad? rubber seems worn but it isn't cracked or popping out yet(although it looks like it is almost there kinda). I heard that pulling them out improperly can damage the balancer?

2. After I removed the balancer again to see what's going on, I noticed one of my crank sensor plastic housing seems a bit pinched? as if the balancer pushed against it or something.. but I thought it's imposible to overtighten balancer in, so how is this even possible? I drove it with 10mph speed around the block, no code came out so I am hoping I didn't damage this brand new sensor as it was kinda expensive. Any thoughts?






I spent all weekend tackling and trying to figure out this problem..it's been a nightmare and there seems to be limited information about this online.. the threads on the crank's side seems and feels fine except for maybe the 1 or 2 beginning thread by the hole entrance so I am fairly sure that I didn't damage the thread? is it just too dirty since the two needs to fit perfectly together or something? I can't seem to find a good way to clean off all the rtvs and debris so far..

thanks lots in advance for input guys..

oldchevy

Looks like the balancer has seen better days and is ready for replacement. As long as the sensor is working, leave it, just trim off the the plastic that is pushed off.over the side.

Little Bear

Looks to me like the sensor was damaged by placing the bolts for pulling the balancer in too far. I'd replace the balancer and go from there as I don't see how not being seated would cause a vibration.

Mario Mare

Thanks guys,

I ordered the new balancer and will arrive in a week, so crossing fingers.
As for the sensor, I just realized you're absolutely right.. I didn't watch out when I inserted those 3 bolts to hold the balancer, stupid me

Burring is another thing I heard that could have caused this? it's really tight space in there.. is it wise to grab my filer and fine sandpaper to try to make it smooth or something?

Will post pic when I do the job!

Weldlife

I'd like to add my expierience with the harmonic balancer on my 4.3 vortec engine because they look very similar.

So the balancer is made of 2 separate pieces of steel molded together with that rubber in the middle. Mine became worn from centrifugal force and made the entire outer ring rotate around the inner part. It only spun about 2 inches from the original position but it was enough to make the car run like crap.
It took me a minute to figure out what the problem was because visually it looked fine until I lined it up with a new balancer.

Good luck sounds like you got the parts you need on the way .

Also, I put a good coat of copper never sieze on the shaft before I pressed the ballancer on .That way you know for sure it's not going to bite or go on crooked.