BEW KP39 Turbo Question

towforce

Veteran Member
Joined
Mar 12, 2005
Location
West Coast, Canada
TDI
Jetta Wagon, 2005, Red
In the process of replacing my 480,000 km KP39 Turbo (with a VNT17). Well waiting for the new turbo to show up, out of curiosity, I pulled the old turbo apart.

There was substantial amount of radial/axle play (but much to my surprise my brand new VNT from IDP had much the same play). The difference, my KP39 had almost .004" of end play, I get the impression this is way over the limit of .001?

One question I had was, behind the exhaust side impeller, there is a disc that was more or less loose and just floating around behind the impeller (lots of play).

[/IMG]

Does anyone have an exploded view of the KP39 parts ?

Cheers

Martin
 
Last edited:

Typrus

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Jun 25, 2004
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BCS, TX, USA
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2002 Black Jetta Sedan GLS/TDI 5mt
You may be surprised how much radial thrust new turbos can have. Some turbos have a limit spec, but a good rule of thumb is that zero contact with the housing is permitted. In fact for the VNT15 that IS the spec!
Axial/thrust play is your kicker- you really want as close to 0 (at least in thou) as you can get. That 4 is truly too high.
As for the ring, I can't speak to this particular turbo but in most it being too loose is a problem. In some, the housing can help retain it.
 

towforce

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Joined
Mar 12, 2005
Location
West Coast, Canada
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Jetta Wagon, 2005, Red
Found a couple videos online and the disc appears to be some sort of heat shield? Mine was sort of floating around behind the exhaust/impeller. Not sure if zero side to side would lock it down? Thought is was a bit strange that something in the turbo that needs to be so precisely balanced would have something that fit so loosely.

M
 

Wilkins

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Aug 19, 2005
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British Columbia
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05 Jetta Wagon 5sp, 10 Sportwagen 6MT
I suspect the play only occurs with the engine off and no oil pressure. It’s a journal bearing is it not? When the turbine is spinning with oil pressure wouldn’t the oil centre the shaft? Rotation of the shaft drags the oil around and floats the entire rotating assembly.
 

towforce

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Joined
Mar 12, 2005
Location
West Coast, Canada
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Jetta Wagon, 2005, Red
I posted this for a little self education on our turbos (curiosity more than anything).. I get the impression, that balance, poor oil and or abuse leads to failure (and maybe the luck of getting a good one?).

Driving them right and changing the oil seems to provide a long life (480,000kms for this one).

I'm still looking for an exploded view of the parts breakdown and specs for the KP39.

Thanks
 

wonneber

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Oct 12, 2011
Location
Monroe, NY, USA
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2014 Jetta Sportwagen, 2021 Atlas,2003 Jetta 261K Sold but not forgotten
One question I had was, behind the exhaust side impeller, there is a disc that was more or less loose and just floating around behind the impeller (lots of play).
[/IMG]
Are you saying there's a loose disk to the left of the impeller in the picture?
 

towforce

Veteran Member
Joined
Mar 12, 2005
Location
West Coast, Canada
TDI
Jetta Wagon, 2005, Red
Yes. I have not pulled the impeller off but disc feels like the hole in it is over sized worn or? Again, more of a curiosity than anything. My VNT17 is in place and running well.

M
 

Beaker80

Well-known member
Joined
Jul 11, 2016
Location
Newmarket, Ont. Canada
TDI
2006 Golf TDI Manual
I believe it's a heat shield used to deflect the exhaust gas heat away from the turbine side of the center housing and the bearing located inside. It is loose until you install the centre section (CHRA) into the exhaust manifold.
 
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