Harmonic balancer fail? (3 Viewers)

[leonard_nemoy]

I get what you're saying, but I disagree on this one. My HZJ80 had no oil contamination on the balancer when it went, and it damaged other components before there were any noticeable noises. Suspiciously, the timing of when it caused problems was also a few months after I went on some serious 4x4 trails. I suspect the extra bumps and jolts from the track are what caused the hardened, embrittled rubber to finally let go.

I don't wait for my tyres to pop or my brakes to fail before I give them attention. Speaking of tyres, would you stick 20 year old tyres on your rig? I did on mine in a pinch, and your response was, and I quote:

And you were right, it was a bad idea. Not sure why leaving ancient rubber holding together part of your engine while spinning at a few thousand RPM until it fails is better?

If a harmonic balancer fails catastrophically it can kill your wallet. If tires fails catastrophically it can kill people.

BIG DIFFERENCE.......

 

[BILT4ME]

Up to this point, there have been few failures. However, as these trucks age, the rubber products get heat soaked, oil soaked, and have been in service for 24-30 years and may have over 300K miles on them.

Most of us have already been replacing the other rubber parts in the trucks such as hoses, window runs, and steering shaft boots, so it comes to reason that we will see an increase in HB failures as time continues to grind on.

Heck, I finally had to replace the rubber in the HB for my Studebaker in 2016!
That was only 57 years after it came out! Granted, it was at 90K miles.........and it was VERY oil soaked for years.

 

[Dullyouth]

Has anyone tried a HB Rebuilder for an LC or any other vehicle?

 

[midfat]

I got enough in my life to stress over. My harmonic balancer should be one. Xanax is cheaper than head gaskets and harmonic balancers and knuckle nuts and lug studs and …

 

[thelal]

Has anyone tried a HB Rebuilder for an LC or any other vehicle?

I'm a FeBest in mine ; Only been in a few weeks with very little mileage covered. Seems fine

 

[OrangeCrusher]

Mine is also wobbling. Took a video of it - best if you play it at about 0.25x speed:

 

[calokie]

Mine is also wobbling. Took a video of it - best if you play it at about 0.25x speed:

“No man
It’s designed to last forever”
“it’s a waste of money to change”

Jk

 

[OrangeCrusher]

haha - sure! It's leaking at the front main seal and I need to replace the radiator. I'm not going to put this wobbling 32 year old thing back on

 

[Kernal]

Definitely is wobbling, post up a photo or two after you remove it from the engine.

 

[OrangeCrusher]

This thing got significantly worse this week. Today the AC belt started squeaking (if you switch the AC on), which it has never done before. Now it's wobbling even more obviously. Video below is less than 100 miles / 5 operating hours after the last video posted above



Good thing is the new balancer has arrived today! I'm still waiting on the radiator. But I don't feel safe driving it anymore with this strong wobble so will start taking it apart tomorrow, and share photos how it looks like.

 

[Kernal]

IME the timing chain cover/oil pump cover may get gouged by the wobbling harmonic balancer, not a big deal if it's a minor scuff.

 

[OrangeCrusher]

So, took it apart. The rubber between the inner and outer part of the old balancer is hard and cracked. It's just falling apart. Interestingly the cracks aren't visible when looking from the front.
@Kernal no damage to the oil pump cover! It had not made contact.
@powderpig , the timing mark on this Febest balancer appears to be correct, see video below. Link to new balancer I bought.





Nothing super special about it. Took me about 6h in total, incl. doing the oil pump cover gasket, front main seal and making the tool to hold the balancer. (I'm still waiting for the radiator to arrive, so it's not completely put together yet).
The front main and the oil pump cover gasket were in relatively good shape, I doubt they were leaking but who knows. The whole area is very oily but the source for that maybe somewhere else.

The only thing I struggled a bit with was figuring out how to put the balancer back on in the correct orientation to the key. It's hard to see this precisely, and I had no idea how close it had to be. I read some other posts here about pushing the key into the oil pan. I was so afraid of this happening without me noticing that I put the balancer half on, then pulled it back off again far enough to see the key had not moved, then put it back on and tightened it up.

Based on how cracked the rubber in mine was, on a sample of one my recommendation is: If you're going to take the balancer off e.g. to replace the front main seal, and you don't know the age of the balancer - get a new one!

 

[Kernal]

Good job.

FWIW, one method before you start installing the Harmonic Balancer (HB) is to draw a chalk line on the top edge of the balancer that's in-line with the keyway.
Then when you go to slide the HB onto the crank it makes it a bit easier (visually) to line up the HB keyway with the key.

 

[BTLSHP]

How many bad 1FZ balancers have you seen?

IDK, but when this failed it was followed by a couple of others on this site and several expressed the view that it was a PM item at 30 years and 235k miles.

 

[dsmud4u]

I know my truck was 320k plus or minus when mine failed.

I remember at the time I couldn’t figure out why the belt kept slipping off until I noticed the inwards separating from the pulley lol

 

[OrangeCrusher]

I put everything back together today and confirmed the timing - it hasn't moved, so the timing mark on the new aftermarket (Febest) balancer is correct.

To my dismay and embarrassment, the oil pump cover is now leaking in two separate spots Not a lot but it's clearly weeping out, maybe one drop every five minutes when the engine is warm and idling. I'm pretty sure I didn't pinch the new gasket. However I also didn't coat the cover with sealant as had been done previously and I think I saw elsewhere recommended. Well, I will definitely not redo this right now - it's going to corrosion protect the area now for a while.

 

[calokie]

Nice follow up post!

10 years dude, life expectancy of rubber. (its stamped on your tires as a reminder)

 

[Rusty Cruiser]

Started working to replace mine today. Rounded out the 1/2” square hole on the balancer holder tool on the first try, then broke a 1/2” breaker bar on the 30mm socket on the second try….trying again tomorrow with double 3/4” breaker bars.
I have a have a new OEM balancer ready to go on if I can ever get the old one off. My old one is starting to wobble though not enough to throw a belt yet.

 

[Kernal]

@OrangeCrusher : The oil pump cover gasket (O-ring) by the book (FSM) does not need sealant and technically a sealant should not be used with an O-ring as it can interfere with the proper function of the O-ring in the gland (groove). Having said that, I've done it both ways, without sealant and no issues 15 years later. One thing IMHO is to not use so much sealant that it gets squished in toward the rotor, but then anything that breaks off should be trapped by the filter.

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"broke a 1/2” breaker bar --- trying again tomorrow with double 3/4” breaker bars"

@Rusty Cruiser : FWIW on my 97 model I grabbed a 5 foot long section of 2" steel pipe (hardware store plumbing pipe) as an extension bar and slid it over a 42" long 3/4" drive breaker bar (around 6-7 feet of leverage), using a 30mm impact socket. Then using all my body weight and leaning back and pulling as hard as I could on the bar the crank bolt finally broke free. Probably took over 1000lb of torque. The sound when the crank bolt broke free was so loud I was afraid either the bolt or the crankshaft had snapped, but they were OK.

Tip: put a sheet of plywood over the rear of the radiator and something thick/protective over the fender inline with the breaker bar/extension pipe so you don't dent your fender if you lose control of of the pipe/breaker bar.