Curious, since I just bought a 6.5L 3500 of the 96 model year and harmonic balancers seem to kill these engines. How does one tell if the harmonic balancer is bad without having to take stuff apart? Am providing a video of the engine running during shutdown, as I read somewhere that a "thump" at shutdown is one main symptom of a bad balancer. Don't know what that "thump" is referring too, and whether or not my engine does it. Much thanks. Truck has 220,000 miles on it. The buzzing in the video was just my phone vibrating with the truck, sorry.
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Tornexted
What are symptoms of a bad harmonic balancer?
Curious, since I just bought a 6.5L 3500 of the 96 model year and harmonic balancers seem to kill these engines. How does one tell if the harmonic balancer is bad without having to take stuff apart? Am providing a video of the engine running during shutdown, as I read somewhere that a "thump" at shutdown is one main symptom of a bad balancer. Don't know what that "thump" is referring too, and whether or not my engine does it. Much thanks. Truck has 220,000 miles on it. The buzzing in the video was just my phone vibrating with the truck, sorry.
![641125]( "641125")
![641126]( "641126")
Welcome to DieselPlace
The first picture you posted shows enough evidence of a bad harmonic balancer.
If you look on the right side of that harmonic balancer you will see a strip of rubber that is warped from being oil soaked.
If you replace the Harmonic balancer you will need to replace the Crank pulley as well because it also contains rubber that has been exposed to oil.
The first picture you posted shows enough evidence of a bad harmonic balancer.
If you look on the right side of that harmonic balancer you will see a strip of rubber that is warped from being oil soaked.
If you replace the Harmonic balancer you will need to replace the Crank pulley as well because it also contains rubber that has been exposed to oil.
You can watch it from down there and it will look wobbly (sideways motion) as supposed to a nice rotation.
When doing replacement, replace the belt and a crankshaft seal behind the balancer for preventative maintenance.
When doing replacement, replace the belt and a crankshaft seal behind the balancer for preventative maintenance.
Here a video of the HB in motion. I'll be sending it to the shop tomorrow for the replacement. Do any of you hear any abnormal sounds in the video?
I will be posting another video after the repairs to see if that noise OkDually refers to and a couple other noises my truck does during acceleration goes away. I tried recording while driving and it's hard to pick up the noise I'm referring to but it's like a wobbling noise that kicks on and off when accelerating, sounds almost like a loud treadmill with a loud bearing when you accelerate on it and it can be a short .5 second or a long 3 second interval and almost always kicks in when accelerating outside of curbs. It happens constantly at slow to mid speeds but it drives perfectly. It's just a little sound so not alarming, but still not proper, coming from the engine since the noise accelerates with it. My truck was used for snow plowing so I don't know if the engine gets retrofitted with some equipment that could make some additional noise but notice the first picture there's another small pulley attached to the HB pulley with a Nascar belt which isn't on my dad's 2500 6.5 truck, don't know what's that for. And there's also a faint vibration that I can feel during idle, you really gotta stay still to feel it, it's faint but it vibrates a little bit every 5 seconds or so. Thanks for the help guys.
X2^^ Hydraulic pump for the plow... If you are not planning on using the plow feature I would remove the pump, pulley and associated lines with the pump
I unfortunately didn't replace that seal because I couldn't find it at the auto parts store, I asked them (the mechanic) what the condition of the seal was, they told me it was OK. Here's a video of the new HB and pulley, if you still notice any abnormal sounds let me know please 
, the sounds I was referring to earlier didn't go away, so I assume and hope it's just the hydraulic pump making those sounds. I'll remove the equipment when I send the truck back to the shop, or I'll try to do it myself. In addition to that I now hear a short "beep" kind of noise every time I accelerate from 0 coming from the back, wonder what that could be. I'll also attach photos of the old HB and pulley for any future readers reading this thread, from what I can see they don't look too worn out, do they? I see one side of the pulley looks quite worn out (Figure 4).
Figure 1:
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Figure 2:
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Figure 3:
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Figure 4:
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, the sounds I was referring to earlier didn't go away, so I assume and hope it's just the hydraulic pump making those sounds. I'll remove the equipment when I send the truck back to the shop, or I'll try to do it myself. In addition to that I now hear a short "beep" kind of noise every time I accelerate from 0 coming from the back, wonder what that could be. I'll also attach photos of the old HB and pulley for any future readers reading this thread, from what I can see they don't look too worn out, do they? I see one side of the pulley looks quite worn out (Figure 4). Figure 1:
Figure 2:
Figure 3:
Figure 4:
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