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Help Diagnosing Cat 303.5 Noise

Kekoa512

Member
Joined
Jan 24, 2025
Messages
20
Location
Honolulu
Hi Everyone. Would love for you to take a crack at diagnosing this noise for me? It's a whistle or whine and it happens near the end of the video. It happens when I start the machine and it'll happen intermittently as I operate. I assume it's hydraulic related. Thanks in advance for the help!
 

Simon C

Senior Member
Joined
Jul 1, 2015
Messages
2,990
Location
Rocky Mountain House , AB., Canada
Occupation
Heavy Equipment Mechanic
Sounds like an Alternator or fan belt, not there but have seen belts before that squeeled the same, once replaced quiet. Micro belts need to have pulleys cleaned with a pick or wire brush as I have seen packed with dirt some times. Or could be a tensioner bearing starting to squeel.
Will have to start somewhere. Are pulleys lined up straight, tensioner working okay.
Simon C
 
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