PDA

View Full Version : wastegate chatter?


ShuswapRedneck
06-21-2009, 12:47 PM
Since I installed my home made intake and turned the fuel screw up a little on my 1992 12 valve intercooled Cummins, when towing up a hill, at low RPM with my foot to the floor, I get a chattering noise coming from the turbo area. When I downshift and the RPM's climb the noise stops until the RPM's drop again. Is it turbo stall, wastegate chatter, or something worse? I try not to let it make that noise very often, or for long periods, but I don't know if it's harmful, or if it's something that requires attention/upgrade. Thanks!

epic3
06-21-2009, 01:35 PM
check the turbo for shaft play

78bronco
06-22-2009, 09:14 PM
the first gen 12 valves dont have wast gates!!! But that being said an thus assuming you have a stock turbo ie h1c

finny
06-23-2009, 12:43 PM
mine does the exact same thing. ive been told its the compresser wheel "cavitating" and the only way to fix it is either a new turbo or one of those compressor wheel upgrades or detune the engine.

Apathy
06-23-2009, 01:24 PM
ya, i'm going with turbo stall, but i might be wrong.

Jeepnut
06-23-2009, 01:40 PM
mine does the exact same thing. ive been told its the compresser wheel "cavitating" and the only way to fix it is either a new turbo or one of those compressor wheel upgrades or detune the engine.

mine was doing that...i had to put in a blow off valve to fix it. The last thing you want is that turbo trying to spin backwards on you

Lynx
06-23-2009, 07:00 PM
hmm compression surge or turbo bark doesn't usually happen at low rpms though. Usually happens when your given'r shit and let off quick. All the boost has no where to go and ends up going back out through the turbo making a chatter sound. A blow off valve would fix that.

finny
06-23-2009, 09:17 PM
its not turbo bark. it is when there is full throttle before the turbo is making full boost. ill find a vid of it

78bronco
06-24-2009, 12:21 AM
or theres too much back pressure get a 4" full exahust from stans headers in auburn washington

Happypants
06-24-2009, 10:48 PM
my chev does that when im really on it in sand or mud, its the turbo backspooling, not good for it,

fumanchu
06-24-2009, 11:21 PM
I've turned the screw on mine and there's no noise.What's different about the intake?

ShuswapRedneck
06-25-2009, 07:24 PM
I made my own intake with a 4" inlet K&N cone filter, a piece of flexible rubber tubing with the wire rings in it (to keep it from collapsing) and a piece of 4" exhaust to couple it. My exhaust isn't the problem, it's 3" straight from the back of the turbo (3" outlet) into 5" stacks. I thought the Holset turbo had an internal wastegate on these things? The sound is made when at WOT but at low RPM, like going up a hill around 80KM/H in 5th gear at about 2000 RPM. It's like a really fast tshhhtshhhhhtshhhhhtshhhhhtshhhhh . A BOV? Cool...I can be ricey!

78bronco
06-25-2009, 10:13 PM
if you have a stock turbo you dont have a wast gate check out my power wagon thread its called turned up the wick theres pics of my stock turbo and my HX40

ShuswapRedneck
06-25-2009, 10:50 PM
Nice job on your Cummins, and I can see the turbo with no wastegate. Dang. OK, so on a limited budget, what do I do to make it stop the compressor stall...which is what I assume it is?

78bronco
06-26-2009, 08:48 PM
thanks.I dont think its compressor stall it could just be the sound of turbo spooling

Trooper
06-27-2009, 12:42 PM
Nice job on your Cummins, and I can see the turbo with no wastegate. Dang. OK, so on a limited budget, what do I do to make it stop the compressor stall...which is what I assume it is?

I would turn the fuel back down a bit.
What colour is the exhaust going from full throttle to idle to full throtle? To big of an intake causes turbo stall. There is no velocity on a huge intake. causes ALLOT of slow moving air. You want velocity on a diesel intake.

ShuswapRedneck
06-27-2009, 08:51 PM
if I rev it, it's black smoke right when I let off. When it's making the sound, it's blowing lots of coal until the turbo spools up again and sounds normal. It only blows smoke when I'm at low RPM before the turbo spools. It made the sound before I turned the screw up as well, I could hear it before I made my intake, it's just a lot louder now. When I took my intake off today, I noticed some carbon on the turbo fins. Is this normal?

78bronco
06-28-2009, 11:50 AM
how much boost are you maken ?

ShuswapRedneck
06-28-2009, 12:18 PM
I have no idea, I don't have a boost gauge or pyrometer on it yet...no money

westcoaster
06-28-2009, 01:09 PM
I have no idea, I don't have a boost gauge or pyrometer on it yet...no money

From the sounds of it pretty soon you won't have a motor either....


Don't be fooling with the fueling too much until you have at least a pyrometer. You can end up melting a piston top pretty quick if your not careful.

78bronco
06-29-2009, 07:17 PM
its hard to melt those pistons I have mine a 1800+ lots and they still look like new. But just rember those motors dont like to see more then 1200 degrees!!!!!!!!