Turbo question - PeachParts Mercedes-Benz Forum

crashone · #1 12-29-2006, 09:43 PM

I pulled an old turbo from an 82 300SD this week, there seems to be some cardon? inside. What is the best way to clean out a used turbo? Air compresser and small brass brushes? Brake cleaner or carb cleaner type stuff? Has anyone done/ tried this? What were your results? Thanks.

Brian Carlton · #2 12-29-2006, 10:00 PM

If the impeller wheel has no radial or axial play, and spins freely........just leave it alone.

If there is too much play in the bearings, it's time to rebuild it........something that a DIY mechanic can accomplish.

Don't go looking for problems on a perfectly functioning turbo.

#3 12-29-2006, 10:03 PM

Quote:

Originally Posted by Brian Carlton

Don't go looking for problems on a perfectly functioning turbo.

Ditto. Don't worry about some carbon.

crashone · #4 12-29-2006, 11:07 PM

Thanks, I guess $40.00 wasn't too bad as long as it works. The one on my car now has some play in the front impeller when the "U" tube is removed, this one is alot tighter feeling. As soon as I can I will install that sucker and let it whine!

Shorebilly · #5 12-30-2006, 06:48 AM

Quote:

Originally Posted by crashone

I pulled an old turbo from an 82 300SD this week, there seems to be some cardon? inside. What is the best way to clean out a used turbo? Air compresser and small brass brushes? Brake cleaner or carb cleaner type stuff? Has anyone done/ tried this? What were your results? Thanks.

You don't say how much carbon? Carbon buildup slows the spool up of the turbine.....

If you want to clean it, you will need new gaskets......for the housing.....but there should be no problem in cleaning the rotor......some carbon solvent, carb cleaner....and a little brass wire brush....and compressed air......but if you do clean it....make sure that you do it well.....the carbon deposits there were accumulated at high RPM.....so they are sorta dynamically balanced......so if you don't clean it completely, you may wind up with a vibration problem.........just be careful, don't bend any fins......

Oh yes, mark the housing before disassembly so that you know which way the spigots go when reassembly......

SB

Note: I used to have my engineers disassemble and clean my auxiliary/generator engine turbos, whenever the exhaust temperatures began to climb.......the main propulsion engines had water washing connections, for washing while running (at reduced load) and we used to do this after long river passages, or just before we headed across the Ocean.....also of note, there are some that inject crushed walnut shells into the rotating turbo.....supposed to clean them like bead blasting

Brian Carlton · #6 12-30-2006, 08:57 AM

Quote:

Originally Posted by Shorebilly

Note: I used to have my engineers disassemble and clean my auxiliary/generator engine turbos, whenever the exhaust temperatures began to climb.......the main propulsion engines had water washing connections, for washing while running (at reduced load) and we used to do this after long river passages, or just before we headed across the Ocean.....also of note, there are some that inject crushed walnut shells into the rotating turbo.....supposed to clean them like bead blasting

You're referring to much larger units with significant clearances.

I know of nobody who injected crushed walnut shells into a Garrett T3 and posted said results on the forum.

I'd strongly advise against such a practice.

I'd again strongly advise leaving well enough alone. The risks of improperly getting the unit back together, or contaminating a bearing outweigh the benefits.

Shorebilly · #7 12-30-2006, 10:02 AM

Quote:

Originally Posted by Brian Carlton

You're referring to much larger units with significant clearances.

I know of nobody who injected crushed walnut shells into a Garrett T3 and posted said results on the forum.

I'd strongly advise against such a practice.

I'd again strongly advise leaving well enough alone. The risks of improperly getting the unit back together, or contaminating a bearing outweigh the benefits.

I did not say anything about running walnut shells thru these li'l bitty turbo's....no do I advise water washing....just posting a comment regarding the cleaning of some units.......

Also note that I said "Engineers", not mechanics.......I would think that most folks who wrench on weekends would not consider themselves to be engineers......

And I will say again....if you don't know what the item that you are workin' on does, and how it works.....leave it alone.....

Mr. Carleton, I am a bit surprised here.....you seem to think it OK to screw around with the IP.....which is a far more precision instrument than a turbo charger is......and can cause much more damage to an engine than the turbo can......

SB

Shorebilly · #8 12-30-2006, 10:12 AM

Quote:

Originally Posted by Brian Carlton

IIf there is too much play in the bearings, it's time to rebuild it........something that a DIY mechanic can accomplish.

As I read the original post, the actual functioning of the turbo is an unknown at this point......I gather that the turbo with the carbon was purchased for $40......and all that is known is that there is less end play in the unit than there is in the one that is functional on the car......

If a decent DIY mechanic is capable of rebuilding a turbocharger.....then he should be equally as capable in cleaning it, without doing any damage to the unit......

Folks: please note that this only my personal opinion......

SB

In all reality the turbocharger has only one moving part...how tough can it be??

crashone · #9 12-30-2006, 01:54 PM

Good discussion here. I'm not planning on running walnut shells or water through this turbo. The operational characteristics of this turbo is an unknown factor however given that there are only so many moving parts, and that both impellers spin freely I am hoping that it will function correctly. I figured for $40 bucks what the hell, if it doesn't work I will have one to rebuild without putting my car out of service. Really I was hoping to clean it up before installation. I think compressed air will do what I'm wanting to do. Thanks for the input. Oh, I also pulled an excellent rear trailing arm for $20.00.

ConnClark · #10 12-30-2006, 05:11 PM

Use WD40, an old toothbrush, and paper towels to clean the carbon off the turbine. Leave the carbon that is adjacent to the turbine blades on the walls( It helps prevent gases leaking around the blades). All other carbon is fair game.

Brian Carlton · #11 01-02-2007, 09:58 AM

Quote:

Originally Posted by Shorebilly

Mr. Carleton, I am a bit surprised here.....you seem to think it OK to screw around with the IP.....which is a far more precision instrument than a turbo charger is......and can cause much more damage to an engine than the turbo can......

SB

.........please direct me to the post where I suggest that it's OK to screw around with the IP.........????