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View Full Version : Scream-squeal under load with new belt and pulleys


ashe350
02-09-2017, 12:12 AM
On 2005 Sprinter 3500 (Winnebago View) I've got loud scream from engine when pulling hard on the road, especially when climbing a grade, but there's no noise in the shop except at very high RPM. Then there's so much engine noise that it's hard to pinpoint where the scream comes from. No noise at low rpms or shut-down.

Shop has replaced three pulleys and belt, but no luck, scream is still there.

What's next? Alternator? Is there a fix short of replacing the whole alternator? Water pump? Turbo?

Thanks for ideas. First Sprinter, just bought it.

Any ideas on how to diagnose when it screams only while driving? Thanks

lindenengineering
02-09-2017, 02:02 AM
Exhaust manifold to head leak perhaps!
Leaks mostly at the front just above the turbo!
You will have a black patch on the head to verify
If not check for a small pinhole split in the turbo charger hose work.
Both maladies can be verified by doing a stall test!
Dennis
Mechanic

misterbond10
02-09-2017, 04:46 AM
Both maladies can be verified by doing a stall test!

Very curious, how do you perform a 'stall test' and what is it? Thanks

lindenengineering
02-09-2017, 06:18 AM
Well you make the engine develop all it power in stationary setting!

Get the engine warm.
Apply parking brake and foot brake firmly! And I mean firmly with your left foot!!
Select drive
Floor the gas pedal and the engine will rev to only about 2200 to 2500 r/.m stalled by the torque converter.
Now since the transmission is absorbing all that power it gets turned into heat. So do not do this test for more than 15 seconds TOPS!
If you need to repeat the test let the engine and transmission cool for one minute before repeating. Read important!
Dennis
Mechanic

misterbond10
02-10-2017, 01:24 AM
neat, first I've heard about this test....Why is it called the 'stall' test?

I have an 06 and the engine power gets cut anytime the brake light comes on. So you cant really ride the brakes to heat them up, burnouts, etc.

ashe350
02-27-2017, 05:44 PM
Update--squeal is gone!

I had the straight aluminum pipe replacement for stock turbo resonator.

I installed a Dorman $30 resonator and that fixed it. Thanks for info from CPH28 who had the same problem w/ same vehicle. Wonder if the 8500 pound weight of Winnebago View causes the straight pipe to squeal under load?

Carrying a spare resonator.