Do harmonic balancers on 4.0's...

fail catastrophically or just start wobbling and are detected visually.

Are they servicable or an oem part?

Thanks,

sv,

Mike

On the 1st question, my dampers rubber is peeling out but there are no vibes even at freeway speed. I'm changing it this weekend anyway. I have never seen a vibration damper let loose and catastrophically fail, but that's just me and I don't want to chance it. A rod buddy told me he trimmed the rubber and inserted filler in the groove several years ago with no ill effects on his car (t-bucket?) but that doesn't sound prudent.

On the 2nd question, I paid $58 at my local parts store, (not a zone, checkers) but the local store where the parts tend to be a higher quality.

Tom

If you pay attention to stuff like that then they don't fail catastrophically. I'd say the ones that seem to have been on their way out for a while but the owner didn't notice the rubber coming out or the balancer sliding off-line.

I've heard of a bad harmonic balancer causing a loud knock that is difficult to pinpoint.

mikeny59 said:

fail catastrophically or just start wobbling and are detected visually.

Are they servicable or an oem part?

Thanks,

sv,

Mike

Click to expand...

Just had mine replaced.. Thru a belt on the way to work.. Well actually, it ate half of it... It had been squeeling for about 70k miles.. Never knew what it was... It was more than obvious when you looked at it, that it was finally really out...

$60 is average cost for the HB... I had the mechanic do it (it happened 60 miles from home, didn't want to chance the ride back)... $356....

mikeny59 said:

Do harmonic balancers on 4.0's fail catastrophically or just start wobbling and are detected visually.
Are they servicable or an oem part?

Mike

Click to expand...

Mike,

The harmonic balancer on my stock '92 XJ 4.0 was wobbling and my
front main seal was leaking oil badly.
My mechanic noticed this, and that the serpentine belt was worn (and might be the original belt!) and recommended replacing all the parts at the same time. I agreed.
He explained that if you don't replace the harmonic balancer, it can fail and take the belt out with it, possibly damaging the engine in a way that might require a rebuild.
I figured that a few hundred dollars repair was better than a few thousand.

I had him do all of the work, and it cost $300 including parts and labor.
The belt cost $75. I don't remember what the HB cost, but it was about the same as the belt or maybe less.
I don't think he had to get OEM parts for anything, as he would have informed me of the delay while parts were obtained.
Here where I live in the Rocky Mountains, Jeeps are common.
My mechanic keeps certain Jeep parts in stock because they require replacing often, so I can't say for certain that it wasn't OEM, but I don't think it was.

My advice is the same as my mechanic's advice: replace it before it fails, or risk damage to your engine and a towing charge.
It's also nice to have piece of mind.

Hope this helps.

Within the last two weeks I've replaced everything related to cooling - including idler pulleys. Well, the rad is next, still deciding whether to replace or pressure test and boil. Three year old GDI, no problems so far.

Noticed the damper wobbling just a bit, decided while I have the rad off to do the idler pulleys, might as well do the damper, and any seals/gaskets that are accessible. Friend at dealer quotes about $60 out the door.

Really trying to put about 1 -1.5k$ to make reliable into my baby, while trying to buy a home in nh, a new car payment for the trips from LI, NY is not really in the master plan.

thanks all for the quick and detailed advice..

sv