CAT 320C squeak noise at boom

[Gary Layton]

SN PAB06638
I have just started noticing a squeak noise that seems to be coming from the boom as it raises or lowers or when movement stops and the boom is bouncing a little. At first I thought the piece of wood might be stuck between the cab and the boom and it was squeaking but I don't think that's the situation. See if you can make out the noise on this video.
I keep it well greased, we grease it every 10 hours. I see grease at each boom pin and it looks fresh. In the morning I plan to clean each boom pin thoroughly and then as I grease it be sure I'm getting grease throughput so that it oozes out around the pen.
I think I heard the noise as I was tracking out of the swamp tonight whenever I was tracking left or right. So I don't know if that means it's a hydraulic issue or if that tracking jiggles the boom and whatever is making the squeak made it because the boom jiggled.
Does anybody recognize that noise?

 

[Nige]

I see grease at each boom pin and it looks fresh.

What about the boom hoist cylinders.?
Sounds like a squeaky pin to me.

 

[Gary Layton]

I will look at them tomorrow. Thanks for the lead.

 

[Coaldust]

Ouch! That’s hurting my ears. That’s a squeaky pin.

 

[Gary Layton]

A pin was my first suspicion...I've never had one squeak before. I'll clean and check all the boom related pins and grease them until they ooze fresh grease.

 

[Hffhvg]

Probably boom cylinder pin. Try to set the hoe attachment on the ground so the pin isn’t strained and rotate it around so the grease gets evenly distributed.

 

[Gary Layton]

Good input. I'll see if I can scooch it around some.

 

[Hffhvg]

Good input. I'll see if I can scooch it around some.

You’ll need some good leverage. If it squeaks theres an area that hasn’t gotten grease and “fused” to the bushing.

 

[Nige]

I would suggest to first try greasing all four (upper and lower) boom hoist cylinder pins without trying anything special. You may well find (fingers crossed) that three pins take grease easily but the fourth will not. At that point you have found your smoking gun and can concentrate on the particular pin that won't take grease. See how you get on.

 

[Hffhvg]

I would suggest to first try greasing all four (upper and lower) boom hoist cylinder pins without trying anything special. You may well find (fingers crossed) that three pins take grease easily but the fourth will not. At that point you have found your smoking gun and can concentrate on the particular pin that won't take grease. See how you get on.

Good point. I had a squeaky boom coming from the pin when I bought an used excavator and couldn’t rotate the pin even slightly. I just greased that pin three times more regularly and the squeak was gone in about a week or two.