When should you replace the harmonic balancer?

Everybody always says every 500,000 miles it's a good idea to put a new one on.
Or should I say , that's what is recommended.

 

I believe I read somewhere that the harmonic balancer manufacturers recommend between 500-750k depending on the nature of your travels. At some point they stop absorbing the torsional vibrations. And they don't call it a harmonic balancer, it is a torsional damper. There is a you-tube video from Pittsburg Power that shows one that has been cut open to see what it does.

 

I didn't mean to scare you ozdriver with my experience. It is hard to say why mine broke. The original balancer looked fine when it was off but didn't investigate it further. I know the cranks in certain prefix cat engines were prone to breaking from what i understand was bad casting material.

 

Someone was talking about this a year or two ago on this site, got me worried. So I went and talked to a Cummins mechanic who has 19 trucks, all Cummins power. Some N14, but most are now newer ISX.

His N14's haul heavier weight and have more miles on them than mine. He has never seen one fail and wasn't too worried about it and told me it was nothing to worry about.

So that's where I left it, I'll replace it it when I hit the 2mm mark in a couple years. lol

 

There are different styles of dampers. Some are viscous and have a fluid and weight inside. Any dents/obvious damage can impair the free movement of the weight and its toast. Same with fluid leakage from the damper. Others have rubber in them. When the rubber starts to crack and fall apart its toast.

 

Have you done any Preventative Maintenance on your N-14 like bearings etc?

I have a N14 too and I have never touched the internals, just a had Overhead done a little over a year ago because I needed to replace a injector.

 

Its not so much that a ballancer fails, but the silicone inside the balancer hardens over time. Once that happens it ceases to be able to do its job.

 

Rolled in some bearings couple years ago and replaced oil pump for a low oil pressure situation. Turned out to be a loose wire on circuit board in the dash.

Did the overhead this summer because of leaking cam follower.

Replaced the turbo about 4 years ago along with 1 injector.

That's all the major stuff I've done to it.