Turbo makes sh-sh-sh-sh-sh noise.

[ScottB]

I can't figure out what is going on. I've got the Banks exhaust housing on I'm not sure what size but I think it's a 12cm or 14cm. It's wastgated but the wastegate has never been hooked up. It only does it when lugging the engin. Above 1600rpms it pretty much stops. At lower rpms it will shudder if pulling then as I gain rpms it will slow and finally stop. Can anyone help me? I have checked the connections to intercooler ect.

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93 W350 5spd White 3. 54 gears 4" stack Powerwagon Injectors. Headache rack with lights. Cummins Mudflaps. 2" lift on seat. Goosneck ball Beefed up reciever. Fog lamps, Back up lights. CB 98 Factory sound system

 

[Jones]

Scott, When I got into my turbo I found an oily carbon build-up on the inside of my compressor side housing and definate rub marks from the compressor impeller, it probably wouldn't hurt to check the shaft side play. My Cummins manual says . 012 to . 018. You should be able to pull the housing and check both without even pulling the turbo. Good luck, Jones

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Jones
'84 Ramcharger w/CTD, non-gated 12, torqflite, NP205, Dana 60 and 70 w/ 3. 07s. Looks more or less stock.

 

[B.G. Smith]

What is your boost pressure when this is happening and is it steady?

 

[ScottB]

My boost pressure used to be between 10 and 15 pnds when this occured. But since I put the powerwagons on it has mooved to 20 to 25 pnds. And no the boost is not steady the needle on the boost gauge will bounce.

 

[B.G. Smith]

I don't know if this is possible or not but it sounds like the turbo is surging, what happens is it reaches it's maximum pressure for the volume of flow at that particular rpm and the flow stops and comes back through the compressor end of the turbo then starts all over again. I would think this type problem would only occur if the turbo was way oversized or the pressure went pretty high without a wastegate.

 

[Wirenut]

Mine does that too when I lug it gettin into 'er. It bounces around 20-25psi, then smoothes out and climbs the rest of the way towards 40psi just as smooth as can be. I never really put much thought into it and don't usually notice it because I'm hangin on for dear life when I'm in it that hard! #ad


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• '93 250 LE 4x4 5spd 4:10 Loaded,dual 5" chrome stacks,12cm² turbo(37psi),PW injectors,K&N,pyro/boost,US Gear E-Brake,tool box,CB,10" AR rims, 285/75/16 Bf goodrich. "wirenut_21529" on Yahoo Messenger
• '97 Ford B-Series school bus (5. 9 Cummins!)I'm gonna Bomb it!
• '94 GMC 2500 6. 5L Turbo

PICTURES.

 

[Jones]

Just something to think about and its really bonehead science ( I can only say this because I did it to myself). When I did some turbo work to mine I didn't get the clamps tight enough on the flex hose to the cross-over pipe and I got a lot of the symptoms you've described, odd noises and flutter in the boost gauge. Hope this helps, Jones again

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Jones
'84 Ramcharger w/CTD, non-gated 12, torqflite, NP205, Dana 60 and 70 w/ 3. 07s. Looks more or less stock.