Hi,

If this has been covered, please direct me to the correct thread.

I have a 1992 300D with 87 om603 turbo in it.

The turbo appears to be Garrett T3 with an external wastegate with a long rod, located on left hand side underneath.

It has been leaking oil from the (aftermarket) feed line for a long time, so I decided to take it out to clean and reseal, and install a proper feed line.
Found out that the wastegate rod cannot be moved by hand at all.

1) Is there a tutorial how to remove the turbo from the car? What should I remove in which order?

2) Regarding the wastegate, assuming that it's not the actuator issue, how to address that? The circlip is hardly accessible, I've seen some people undo the 4 exhaust bolts and spin the turbo to gain access, then soak in penetrating fluid. I am not sure how to spin it.

3) Should I buy Kent Bregsma special toolkit?

4) How do I prime the turbo after the assembly? Assembly lube is not enough?

Any professional service is out of question (independent graduate student).

Thank you,
Filip

Filip,

What is your level of ability? The factory service manual is your best source of info, I'm pretty sure it is available free online. Maybe not very user friendly, but free. This is a fairly straight forward job (Remove and replace the turbo) but very tight access, so you'll need to be sure you use quality tools and don't round-off any nuts or bolts. Use plenty of a quality penetrating fluid and give it time to work.

Basically you'll need to remove intake manifold cross-over pipe, the bolts holding the turbo to the exhaust manifold and the exhaust down pipe, and then the feed line. I think the oil return line will come loose when you remove the turbo. There is a large heat shield between the turbo and the coolant reservoir, consider removing that to get better access to the exhaust bolts.

__________________
Respectfully,
/s/
M. Dillon
'87 124.193 (300TD) "White Whale", ~392k miles, 3.5l IP fitted
'95 124.131 (E300) "Sapphire", 380k miles
'73 Balboa 20 "Sanctification"
Charleston SC

I think Kent’s turbo tool kit is for the 617 turbo. It might help but I don’t recall having trouble with basic hand tools on the similar 603.971 turbo. Don’t forget the pesky bracket from the bottom of the turbo to block if the 602 has one.

I don’t know if you can pull the pressure actuator rod by hand. I take it it’s not the 602’s original vacuum actuator. Where does the actuator get its signal?

Sixto
98 E320s sedan and wagon
02 C320 wagon

If it's a '82 it should have a 602. Is the 603 a transplant? The stock turbo on a 602 is a T25. The wastegate can freeze on these, due to rust and carbon accumulation. Once it's apart, a good cleaning and a soak in penetrating oil will free it up.

Thanks for all the replies!

It's om603 swap from 1987 into 1992 chassis. EGR and cruise control delete.
There is nothing etched on the compressor housing to tell me what turbo it is. I bough a kit with 360 dynamic seal on ebay

My level of ability is intermediate, just did transmission fluid, filter and spring change, oil change, monovalve, door lock actuator, LCA bushings in the rear, rewired audio, replaced seatbelt, resoldered CCU...the list is growing and this weekend I'm retrofitting adjustable steering column (will create tutorial). It was $13

I will take some pictures today.
It was a cheap car to begin with but I do want to drive it for the next 5 years with minor maintenance.

I would work on removing the actuator. A bad actuator can not be moved by hand, maybe you could apply a 10 or 14 psi pressure to the actuator directly and see if thats the problem.

__________________
92 e300d2.5t
01 e320
05 cdi
85 chev c10

Ah, I thought you meant 603 T3 bolted to a 602.

Most 603.96s came with a Garrett turbo but some came with a KKK. The KKK has an integrated actuator with a metal signal line and no exposed actuator rod. Sounds like you have a Garrett.

The 603.96 turbo has an air recirculating valve (ARV) on the compressor housing. There’s a device cast into the comorsssor housing with a vacuum nipple. Seeing that all but confirms it’s an original 693.96 turbo.

Sixto
98 E320s sedan and wagon
02 C320 wagon

Here are pictures: https://imgur.com/a/sQENt0G
Seems like downpipe has been welded.
Should I unbolt the turbine housing at turbine or further towards downpipe (two bolts visible with a flange between) ?

As you can see from the pictures, it's not quite OEM.

That isn’t an ‘87 300D exhaust manifold (5-6 separate rather than 1-2 separate) or turbo (no ARV). That’s a US 603.971 (92-95 SD) or Euro exhaust manifold. That’s a 602 mixing pipe. I can’t tell if it’s a T25 or T3.

Check the horizontal surface of the block just ahead of injection pump for the engine serial number. It should begin with 6039xx xx xxxxxx.

Sixto
98 E320s sedan and wagon
02 C320 wagon

Sweet another .971 exhaust. The .971 has its own specific oil feed hard line. It's kind of a neat design. You should try to find one of those.
Here's a pic of mine.
https://i.imgur.com/xNLk2dr.jpg

It looks like you have the turbo from a .971 as well. It should be a 55 trim T3. It's marginally more efficient than the 50 trim found on 87s. Rebuilding a T3 turbo is a piece of cake with any generic kit. The biggest problem with these turbos is they get coked up with exhaust soot. Disassemble, clean it out, swap out the bearings and you're good to go. Also make sure your oil drain and large enough. Most turbo leaks are caused by poor oil drainage.
https://imgur.com/a/JHTUtt9

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CENSORED due to not family friendly words

I found the number stamped behind 2nd injector. It reads "603 016 14 01".
So I have the dreaded #14 head? Lol. 230k miles and running great with very minor blowby. PO said he transplanted a few things from 250D and 350SDL. He has his private junkyard with old MBs. Car slowly seeps oil near the shut off valve though, not gonna touch that anytime soon.

As to the turbo, I found "Garrett" stamped on the rear of turbine housing, so it's T3 for sure. Found "M11" on the compressor housing. The rest is so dirty it's unreadable.

Got a metal feed line similar to yours tjts1, from my friend's om603. It should fit. Got all the paper gaskets and two o-rings for drain pipe too.

Thanks for comments. I will probably start in two weeks and do it over weekend. All I need is a good 10mm flarenut wrench and carb/brake cleaner.

Also, is there a consensus regarding the torque value of center nut of the turbine?

Turn it til its good and snug. Remember its a reverse thread.

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CENSORED due to not family friendly words

I’m still curious what block it has which you can tell from the 6039xx number ahead of the injection pump.

The control rod sensor connector inboard of the shutoff actuator can leak. Nothing to do about it but fear the IP apart to replace an internal seal. The shutoff actuator itself has an o-ring as does the stop lever. Oil cap leak from the IP if the ALDA isn’t properly tightened. AFAIK there isn’t a seal for the ALDA.

Sixto
98 E320 sedan and wagon
02 C320 wagon

No idea where to look for that number...

It seems like the black plastic part is leaking. Pics: https://imgur.com/a/HzeVnOU

Tested the wastegate today with a vacuum pump. It works: opens about 11psi a little, then more up to around 20psi. One problem less...

This is a 603 with the cylinder head off. Follow #1 cylinder towards the IP. That ledge just ahead of the IP has the serial number etched in it. Might need to clean off the grime.

If what’s leaking oil in the IP is the black plastic thing inboard of the shutoff actuator under the ALDA, that’s the control rod sensor connector. It can’t be resealed from outside. The IP has to come apart which isn’t something just anyone should attempt at home.



Sixto
98 E320s sedan and wagon
02 C320 wagon