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-   -   Rebuilt Turbo, no power/ loud wistle (http://www.peachparts.com/shopforum/diesel-discussion/192206-rebuilt-turbo-no-power-loud-wistle.html)

JDmills 06-24-2007 04:25 PM

Rebuilt Turbo, no power/ loud wistle
 
I just finished putting together a turbo I have attempted to rebuild.. with frustrating results so far.

It is back together, and on the car, so I took it down the road, to warm up the engine coolant, as I changed the thermostat also.. the turbo makes a rather loud whine, which shows up at about 2000RPM. Also there does not seem to be much boost, as the car has no power, and really does not want to climb above 2200RPM. in the 3 miles I drove the car it did get to 3000 with out any noticable change (good or bad) in terms of noise, or any indication of a fuel enrichment taking place.

Any suggestions? the Impeller seems to spin just fine, But It worked better when the bearings were making noise.

79300sdtd 06-24-2007 04:28 PM

wild guess but you might have an air leak somewhere on the compressor side. possibly around the housing.:confused:

Cervan 06-24-2007 04:45 PM

yeah thats what i would have guessed unless they dropped the compressor wheel and damaged it :/

ForcedInduction 06-24-2007 04:47 PM

Make sure the air line going to the ALDA is intact.

psfred 06-24-2007 07:54 PM

Air leak. Make sure you didn't leave an o-ring out of the pressure side outlet housing or something.

Also verify that the wastegate linkage is intact and working.

Peter

larry perkins 06-24-2007 08:06 PM

jd
 
the last time that happened to me i missed the inspection when rebuilding the turbo.
the turbo compressor wheel had rubbed the throat and wore some off the wheel,if there is too much gap then the thing will really make some whistling noise.
look at thw wheel with a light and see if the outer edge of the alum fins arent rolled over some.
larry perkins lou ky

JDmills 06-24-2007 08:21 PM

After I calmed down a bit, I came to a simmular conclusion... Will check the ALDA boost line, and the o-rings around the turbo to intake manifold area...

I hope I dont have to take this thing apart, although I am getting better at it, it is not something I look forward to, especially since it is the daily driver, and driving the P/U is dang expensive at 13 mpg..

GREASY_BEAST 06-24-2007 08:27 PM

Are you sure you put everything (compressor wheel, shaft, and turbine) back together in such a way as to ensure that they remained balanced?

JDmills 06-25-2007 12:58 PM

yeh, something is amiss. I found the the intake/exhaust manifold gasket is not quit doing the job, or it is too loose... as there are soapy water makes bubbles present, when the motor is at a fast idle..

So that means there is some back pressure in the exhaust system.. so I put a boost gage on the intake ALDA line, and found vacume. What The Heck? a vacume, with the woosh of turbo noise? check the wastegate? I did not touch it, although I did disconnect the hose, it should only be opening when there is too much boost right? and that would still produce a little boost I would think. turbo is turning too slow? It seems to turn freely by hand.. wonder what else could cause a vaccume.

1983/300CD 06-25-2007 01:09 PM

Reconnect your wastegate hose.

JDmills 06-25-2007 01:39 PM

Quote:

Originally Posted by 1983/300CD (Post 1545814)
Reconnect your wastegate hose.

Done.

where could there be a leak on the intake side that would be large enough to produce a vacume? Or is it that the leak, reduces signal to the alda, thus there is a vacume as a result of no fuel enrichment? Nope that can't be it.

ConnClark 06-25-2007 03:48 PM

I might mention that a vacuum is not uncommon when your free revving the engine. When you say you have hooked a boost gauge to the ALDA line I would tend to think that you are not measuring boost while on the road. The engine really needs to be under load to make boost. You can have someone stand on the brakes of the car and wind the engine up with it in gear to get some boost.

To me it sounds like its an air leak some place. Check for leaks around where the compressor housing mates with the intake manifold.

JDmills 06-25-2007 05:09 PM

Ok, I have tried to put some compressed air to the turbo inlet, so that I can put soapy water around all the posible joints/surfaces that may leak.. soapy water is useless, has any one else got a better idea?

There seems to be air bubbles comming from the intake manifold to head surface... I bolted this manifold on once, had to remove it, and then bolted on again using the same intake/exhaust manifold gasket. never ran the car, but, is that why there is a leak there? (do I need another intake/exhaust manifold gasket?)

also, can one get the turbo off with out taking the exhaust manofold off as well? I struggle to find enthusiasm to wrestle the whole thing off again, except that seemed to be the only way when I took it off the first time..

oh well, I gotta learn how this all works some time, why not now.. Conn Clark, I agree, that the turbo-to-intake manifold seems to be a likely spot for a leak. I only replaced one of the O-rings, as the "turbo mounting kit" from Elring only had one.. guess that was stupid of me.

ConnClark 06-25-2007 05:25 PM

It wasn't stupid, it was cheap. Of course 99.99999999999999999% of us here are cheap and would have done the same thing. I think its possible to take the turbo off without removing the manifolds(it is on my California emissions car).

I suppose it could also be a leak in the EGR hose. That would rob the turbine of power and hence there would be no boost.

Edit: Any leak is a bad leak if its anywhere in the path between the compressor and the turbine of the turbo.


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