Community Forums

dtreid · 11-20-2018, 08:19 PM

I have a squealing sound that comes and goes on my 2013 Cummins ISC 300hp.
Can't really tell where it's coming from but certainly near the rear of the engine/turbo.

Anyone else experience this?

https://www.youtube.com/watch?v=SQH1CJjApM4

Ray,IN · 11-20-2018, 08:29 PM

Nothing is heard out of the ordinary in the video. On mine, when parked, a shrill sound begins to commence at about 1,000 RPM, it is the turbocharger spooling up, it cannot be heard when driving. I recommend closely inspecting the exhaust manifold for cracks and leaks, also check the manifold gaskets for leaks. You should see the obvious black stain from any such leak or crack. The Cummins ISC engine is known for cracking from supporting the full weight of the turbocharger and associated piping.

GreaTOne65 · 11-20-2018, 08:31 PM

Sounds like an intake air leak. Does the squeal go away when you rev it up?? What does it sound like then?

dtreid · 11-20-2018, 09:10 PM

Squeal comes and goes from just off idle to full throttle.

Was wondering if it has something to do with the egr system...sometimes it will do it when idled at 1000rpm parked then just stop like someone turned a switch.

funjnt · 11-30-2018, 04:28 AM

Have you had any luck with your noise? I have developed a similar noise I noticed on my way to fla this year. I can only explain it as a rotational noise as a pulley rubbing on a metal cover so to speak. I am going to take my belts off when I get back to fla and check the water pump and pulleys and see if they feel like they are loose or needing replaced. Let me know your progress on this one.

1doodadd · 11-30-2018, 07:50 AM

Check all the hump hoses from the intake side of the turbo to the intake itself. sounds like you have a hole in a hump hose or a broken clamp used to secure a hump hose to the hard intake line. I recently changed all of mine and happy I did because while doing so I found one almost worn completely through from rubbing against a coolant line. They were 17 years old and ready for replacement in my mind

RKins · 11-30-2018, 04:56 PM

Could be the belt tensioner - you're supposed to change it every few years (Same schedule as the belts). Mine started squealing shortly after I bought the coach - the cost was like $75. One bolt and you're done.

funjnt · 12-01-2018, 06:25 AM

Ok I see two good things here. One is that I know the sound isn't a turbo or suction sound, it is rotational. Anyway the checking of the intake pipes and hoses is a good idea. I keep seeing that people have dusted engines on here and I am surprised to see this. I agree in checking all intake hoses, clamps and pipes, good one!

I will also check the tensioner and other pulleys, water pump etc. They do go bad and I am not used to the noise they make. It won't be till after Christmas but will check when I get back to fla. I will keep posted although it will be several weeks. Thanks everyone!

funjnt · 05-09-2019, 05:27 AM

Update. I found the rotational noise and it was the... fan bearing hub. Ok yes I know we don't have a fan on the motor but if we did this would be the hub where it would be located. It is also the hub my ac has an additional pulley to run the ac compressor.

I drove coach from Ocala to Myrtle Beach and upon arriving in Myrtle it was worse and easy to find. The pulley was loose to the hand, you could wiggle the pulley.

Now, the ac pulley broke from the oscillation of the bad bearing. Does anyone know where to get this pulley? I haven't searched yet.

Also yes, going to replace the water pump and belt and tensioner while it is home.