Any experienced KP39 Turbo actuator replacement pro's here?

Hi, I bought a Kerma TDI smart actuator replacement for my 2004 BEW Wagon (Jetta.) I see the threads about extending the actuator rod with "all thread" or "all rod" as some call it, using two nuts and lock washers. I know the old actuator must be removed from the bracket, and then riveted on the new actuator. I do have two question for people that have actually done this "jurry-rig" before. I saw all this "don't lose the e-clip" threads, so I bought a bag of 100ct from McMaster Carr (They don't sell them single and it was so cheap I figured why not, I was having to source the M6 metric rod there anyway. Now it looks like the BEW actuator tip doesn't even use a e-clip (confirm?)

Is this style (VNT15) actuator the exact same as the KP39?


1. How do I measure how long of the extension with the "allrod" I have to add?

2. Once the extension is installed, how do I know where to adjust the vane arm to?

I have a mityvac tool and a VCDS. Thank you for your advice. I do my own TB service, so I'm no newbie but working on any of the turbo components is new for me so I'm not afraid to ask you gents.

I did this last fall and it worked out great. I followed the thread here: http://forums.tdiclub.com/showthread.php?t=312966
Yes, this turbo does not use the clip, so nothing to go flying, only two nuts as shown in your pic. The new rod should be the same overall length as the old one. I used the thumb adjuster from the new actuator's rod as the coupler and cut the old rod off the broken actuator to use as the extender.
You'll need to drill some holes in the bracket to mount the new actuator, but I didn't need to rivet anything. The new one comes with studs and nuts for this task.
Check out that thread I linked.. All of the details you're looking for are in there.

I did this mod a couple of years ago. It works pretty well.

As far as adjustment, I got the actuator all set up and installed it on the turbo. Then with the actuator "at rest", adjusted the nuts so that it had just a bit of play (not much, just a bit of slack).

The threads you see for using the Mity-vac to adjust it seem to be for the non-smart actuator on earlier models. Mine never quite matched the numbers reported by them.

Once it's on, take it for a test drive with VCDS running and check the requested vs. actual boost. I got lucky and mine was really close so I left well enough alone.

Thank you both so much for your input! Can you verify:

1. Is the turbo at a position on no boost, when the there no vacuum applied to the actuator (I heard on here one particular model had a a reversed actuator?)

2. The KP39 turbo vane lever position. When it is moved toward the exhaust manifold, is this in the full boost direction, or no boost direction?

mjydrafter-"As far as adjustment, I got the actuator all set up and installed it on the turbo. Then with the actuator "at rest", adjusted the nuts so that it had just a bit of play (not much, just a bit of slack)."

-Where was the turbo vane lever on the turbo at when the actuator was at a rest? Closer to the actuator or farther away? I guess I'm not sure if it pushed the vane lever to full boost or pulls it. I want to mentally do this before I take it off and actually do it.

The lever should pull down with the turbo on the car. The actuator is that same, the rod pulls into the actuator when vacuum is applied. The actuator should be pointed down with the turbo on the car.

With the actuator off it's a great time to make sure that the lever moves smoothly and easily. IIRC there is a spring on the lever, that moves it to it's resting position. So when you have the actuator unhooked, the lever will only move one direction and then should go back when you release the pressure of your fingers.

In your pic of the turbo assembly above, everything should be at rest.

Wow, thank you so much mjydrafter! Perfectly clear and concise (unlike my question...) I totally get it now. Thanks a ton diesel brother!

VincenzaV said:

Wow, thank you so much mjydrafter! Perfectly clear and concise (unlike my question...) I totally get it now. Thanks a ton diesel brother!

Click to expand...

No problem. Us PD guys gotta stick together.

Yup! Lol.

I got done with my classes this semester and started this actuator replacement today. My old actuator was rusty (bad) and I just did new silicone vacuum lines (about two months ago.) I am replacing my N75 solenoid with a brand new OEM one since it likely got damaged by rust too (I blow on to and rust chunks came out.) So all my vacuum lines are replaced. BEFORE I started the new smart actuator replacement, I pulled the actuator vac line and a bunch of rusty water dripped out of it?

How does water (about half of a soda bottle cap max) get in the vacuum line?

I am going to blow all the lines out with my compressor before I connect anything. I just don't want to kill a new actuator or N75. Don't know if that little rust water is associated with the rusted old N75 and actuator or somewhere else in the vac system.

VincenzaV said:

How does water (about half of a soda bottle cap max) get in the vacuum line?
I am going to blow all the lines out with my compressor before I connect anything. I just don't want to kill a new actuator or N75. Don't know if that little rust water is associated with the rusted old N75 and actuator or somewhere else in the vac system.

Click to expand...

It probably got sucked in through the rusty actuator. The line from the N75 to the actuator is quite long and the actuator end is nearly vertical, so I would guess there's only a slim chance that any of that water made it all the way up to the N75 if there wasn't very much. Good idea to blow it out anyways, and inspect the N75 for signs of having water in it. If there are signs of water in the valve, you'll want to look for water on the other side of it as well. IIRC, the N75 valve on my car did have some rust discoloration on the nipple when I replaced my hoses, but I didn't see any water when I disconnected it and replaced the actuator.

Good point Ancestor!

Here are my takeaways:

1. The car runs great! I was exact in measuring the distance between the old actuator body where the rod goes in, and where the VNT lever touches the 10mm nut. I used a high end caliper and got the length spot on. I haven't run the logs yet, I'll do that in a few days. Amazing power now.

2. I bought a rivet gun, but didn't need it. You can see the four spot welds into where the bracket touches the actuator. They were a pain to drill out. Very strong steel. Needed two drill bit, but one was probably on the way out.

3. I blew out all silicone vac lines with dry and clean compressor air. The actuator line (that had rust in it) was flushed with brake cleaner (a smudge) and then high pressure compressor air.

4. I replaced the N75, since rust did make it up to it and didn't want to kill a new actuator and go through it all over.

5. When tightening in the top bracket bot, at the last two-three rotations or so, you guessed it-snap! The bolt broke. I hope enough of it is holding the bracket like a "stud", as the head didn't fall out (yet.) But I had not other options. I hope the lower bolt, and actuator rod itself provides enough support. Just when things were going so smooth. I cleaned the threads of the screws with a wire brush, but didn't have a thread chaser set (Not sure if there would even be enough room to use it on the car.)

Thank you guys so much for all the help!!! The car runs great!

What holds the top and bottom adjusting nuts in place? Are there no circlips? The new Garrett I bought from idparts came with one new clip.
I could not get a clear enough view from the top.

No clips for this to work.

You need a piece of metric threaded rod, and a coupler that matches, the old nuts (or new ones) for the "new" piece of rod.

JB05 said:

What holds the top and bottom adjusting nuts in place? Are there no circlips? The new Garrett I bought from idparts came with one new clip.
I could not get a clear enough view from the top.

Click to expand...

Use a piece of thread tied to the clip so if it goes flying it's easier to find.

I'm going through this as well.
That's what I did:


Now will be replacing it with this:

...with the mods that this implies of course.
It was a none sense for me replacing my kp39a which is in mint condition.

I have the new actuator assembled with the extended rod and coupler. Just want to know what to expect once I get under there.