Crank Pulley..Noise..clank...rattle..

[Hydrauk]

Hello to all!!
I recently found out where the Source of a "Rattle/Clank" noise was comming from on my 97 GMC. This noise was clearly evident when truck was idling.

When belt was removed and truck was running....NO NOISE.

Ok one step at a time. Checked the Vac Pump, Water Pump, Power Steer Pump, Alternator, and Idler Pulley. All seemed okay.

I did remove the Vac Pump, I no longer needed it anyway. Installed new belt. No changes...Noise Still present. I will post pictures of Vac Pump removal later this week.

So this past week I finally Installed Oil Cooler Lines, and a Oil Filter Relocate system. I will post detailed pictures later this week. Ok while under the truck looking for best route of Cooler lines, I looked at the crank pulley, I saw little nick marks and then noticed the rubber ring looked worn. I then tried to spin the pulley...."WAH...LAH" This was where the noise must be comming from. It was indeed spinning back and forth on the rubber ring.

I replaced the Crank Pulley...Clank/Rattle Noise...GONE!!

Tools Needed: 15MM wrench, 15MM Socket, Something to hold Crank from spinning. Once the 4 bolts are removed, the pulley will now pull right off.

I posted pictures...Hope it helps!


Crankshaft Pulley Front.


Crankshaft Pulley Back.


Notice Marks, Where it was banging against the side? Hence the Noise.


Marks shown where pulley was knocking against itself. See the wear marks??

Cheers!
David D.

 

[packratt]

Did you take a look at your harmonic balancer while you were replacing the crank pulley. They have a bad habit of failing also. And not too long after they fail the crank breaks.

 

[vail426]

I would say the rule of thumb is to replace them as a set. Pully and balancer.

 

[Hydrauk]

Hello!

Thank you for the input. I did have a "Look" at the balancer when I installed the new crank pulley.

Yesterday I did indeed check it again, It looked solid, Rubber was firm, and it did not move or slip on the ring when I applied any pressure for movement.

I will now keep an eye on it. Good information. Thanks again fellas!

Cheers,
David D.

 

[JiFaire]

David, thanks for sharing, and for the pictures - they help others to get a peek at something we ALL need to check more often. --this is going to the 6.5 Technical Reference library.

Packratt's comment is dead-on... when things let go in the front end, the crankshaft becomes a collection of separate parts operating in formation.

Not a good thing!

Glad you caught yours before that happened!

 

[Hydrauk]

David, thanks for sharing, and for the pictures - they help others to get a peek at something we ALL need to check more often. --this is going to the 6.5 Technical Reference library.

Packratt's comment is dead-on... when things let go in the front end, the crankshaft becomes a collection of separate parts operating in formation.

Not a good thing!

Glad you caught yours before that happened!

Hello..and THANK YOU.

I really enjoy this site and all the information, I will continue to help out in anyway possible.

I was told about this site from CTChevy427. He was correct, I have truely gained excellent information, from many of the members.

So a big THANK YOU to all on here.

Cheers,
David D.

 

[Odlaw]

x2 or 3 on replacing both the pulley dampener and the harmonic balancer at the same time.

Detailed pix and instructions in my photo album.

 

[Hydrauk]

OdLaw-
Thanks for your input. I did indeed look at your photo's and now just may go ahead and just replace my balancer to be safe.

Although my balancer seems to be fine and in good condition, as well, the engine runs smooth without vibration.

Cheers,
David D.