Cm870 Turbo noise......new turbo?

[tlzimmerman]

Well I thought I had found the source of my turbo noise....I was wrong. The egr cooler hose was off, and then when hooked up I figured out it was blown. I thought what I was hearing was boost leaking. Opened the doghouse and fixed the egr hose.....still have a horrendous turbo noise.

With the doghouse off I can hear it better. Anytime it builds boost it "shreeks" for lack of a better term. I know its the original turbo with 500k on it, and now I am thinking it is out and just needs replaced. Truck will pull with everything hooked back up, but doesn't have near the power it should and I think it isn't building boost. I cannot find any boost leaks anywhere, and I've been over the charge air circuit with soapy water at each joint now while running at 1400 RPM.

Here is a video of what I am hearing. Anyone want to toss in their .02 on what is wrong? I would be happy to perform any tests anyone can think of to narrow it down. I feel like the turbo is coming off next no matter what. I am planning on getting the ebay inline5....am I going to need it to diagnose this? I assume if I replace the turbo since it is actuated it would need calibrated right?

https://www.youtube.com/watch?v=Lm0svUInNHs

We have about 30 days til the truck needs to run....so I have that long to figure it out LOL. Thank you again for helping out an inexperienced ISX owner.

[trucklogger2]

Faulty turbo mounting gasket maybe?

[Nilao]

Definitely sound like the turbo is closing the nozzle like the egr is requesting it to 80%. Have you pulled the air intake pipe off the front of the turbo and checked the shaft end play?

[tlzimmerman]

Yes.....you can feel a tiny amount of play in the shaft. It is barely there. How much play is acceptable? None?

[Nilao]

A little side play is acceptable but none in/out I believe. Your going to need insite to see the turbo rpm as well as an actuator test. One thing to check would be unhooking the actuator rod from the turbo and turning it by hand to insure it's not binding or stuck. You can also test the piston on the turbo by taking the air supply line off and hitting it with regulated shop air. I'd say no more than 100 psi should give it full movement.

[Rawze]

TURBO MOUNTING GASKET

http://rawze.com/forums/showthread.php?t...8#pid15618

[tlzimmerman]

Nialo thanks for some of the steps on checking the turbo. I can do regulated shop air to check the actuator, and probably should since the turbo is at this age.

Rawze thanks, that sure sounds like that could be it. I don't know when I'll get to work on it again, maybe Sunday night....but I'll start there. I've got 2 combine heads tore apart right now rebuilding a few parts.

[tlzimmerman]

Trucklogger2 also thank you for suggesting the gasket...didn't mean to leave you out!

[trucklogger2]

Hey you bet. With the actuator you can take off the hose at the actuator then start the truck and check for airflow and have someone depress accelerator to rev engine and you should feel airflow increase. The actuator normally moves down 12.5 mm.