Holy Carbon, Batman!

[NMBurb02]

Last night I finally got some time to pull the TB off the Grand Prix and clean it while off the engine. The back side of the throttle plate was pretty nasty and I had to work it with a toothbrush, shop towels, and TB spray for 10+ minutes before finally cleaning it up to my satisfaction. Now the problem is the the SC intake immediately behind the TB:

That stuff is thick and does not want to let go. I tried spraying a shop towel with TB cleaner and using it to wipe the stuff off, but that did not do much. I actually scraped some off with my fingernail and it was probably 1+ mm thick in some spots, like just behind and to the right of the hole in the center there.

How can I clean this stuff up? Is it safe to go to town with a can or two of TB cleaner, a roll of shop towels, and a toothbrush to see what that will do?

 

[Merkava_4]

You might try pouring some Sea Foam onto a Scotch-Brite pad and start scrubbing it if you can get your hand in there.

 

[Artem]

steam cleaner?

 

[david_ES2]

Youre gonna have to scrub with a good brush and have lots of choke cleaner, that or the solvent tank it is.

 

[Roadkingnc]

Leave it, its not causing a problem and will come right back.

 

[KrisZ]

Originally Posted By: Roadkingnc
Leave it, its not causing a problem and will come right back.


My thoughts as well. That amount of carbon buildup is normal and cleaning it up will be an exercise in futility.

 

[beast3300]

You don't want cleaning chemicals in the supercharger, the impellors are coated. The carbon helps seal the supercharger so leave it alone.

 

[Plumber]

So this is a case when grime is good?

 

[Michael_P]

I usually clean mine when the CEL comes on for insufficient EGR pressure which is about every 140K mi. Thats it.

 

[artificialist]

Blasting it with TB cleaner is fine, but don't expect too much.

 

[Clevy]

Originally Posted By: Merkava_4
You might try pouring some Sea Foam onto a Scotch-Brite pad and start scrubbing it if you can get your hand in there.


Seafoam is no stronger than tb cleaner.

OP. Brake cleaner is stronger however if it ain't broke..........

 

[sciphi]

Leave it. You don't want to be rebuilding the supercharger due to getting solvent into the bearings. And, that gunk's going to only go down into the engine once it comes off. Not to mention the EGR port is right there, and the L67 likes a functioning EGR valve.

Try some Techron or another PEA-containing cleaner, along with a known good cleaning oil like Pennzoil Ultra for a few changes. All that gunk is from the PCV and EGR systems, so cleaning out those systems just may clean out the SC.

Also, when's the last time you replaced the PCV valve on that engine? It's easy/cheap to do. Just make sure to get both O-rings onto the new PCV valve or it'll make a vacuum leak.

 

[Merkava_4]

I pretty much disagree with everyone in this thread. If that were my car, I'd be moving Heaven and Earth to get that carbon out of there. I'd be pulling out all the stops - whatever it takes.

 

[nleksan]

While I have become a convert to the Church of Lysholm, lol, I have had a number of centrifugal SC setups on various cars.
The only ways I would really be hesitant to do anything would be if the impeller blades are ceramic, or if the blower has a known issue with the bearing.

Otherwise, I would remove it from the car and clean very carefully. I did this to a 97 M3/2/6 I had that was running an AA Stg3 S/C setup, after I noticed that there was a ton of buildup.
I cleaned everything to like new, including the intake manifold, and found that the CCV/PCV system was junked. I replaced everything with the "cold weather" versions, installed a new and better than the AA one catch can (4 filtration layers with varying size mesh, 14 layers of mesh in all, and Max capacity of 0.4L), and I never had a bit of buildup again.

Funny enough, after doing this, I found that the blower started spooling quicker, making a noticeable amount more torque and reaching peak boost (14psi) about 575-625rpms sooner, the AFR variance was about half what it was prior, intake charge (oversized dual pass FMIC with both electric pull fansto pprevent heat soak, and 8-nozzle fine mist water/methanol IC sprayer) dropped 12-19F under boost and a bit more at idle, and throttle response was markedly improved.

I am confident that some of that was from the removal and replacement of junked PCV parts, and the installation of a 10x better and more efficient catch can (it was designed so that when full, it didn't completely block return air, instead it had a suction valve that would allow a small amount of the collected oil back into the sump).
Still, I would never want to have a caked up impeller; the potential hot spots will likely end up causing more problems than some SeaFoam and a toothbrush.

 

[SOHCman]

Originally Posted By: nleksan
While I have become a convert to the Church of Lysholm, lol, I have had a number of centrifugal SC setups on various cars.
The only ways I would really be hesitant to do anything would be if the impeller blades are ceramic, or if the blower has a known issue with the bearing.

Otherwise, I would remove it from the car and clean very carefully. I did this to a 97 M3/2/6 I had that was running an AA Stg3 S/C setup, after I noticed that there was a ton of buildup.
I cleaned everything to like new, including the intake manifold, and found that the CCV/PCV system was junked. I replaced everything with the "cold weather" versions, installed a new and better than the AA one catch can (4 filtration layers with varying size mesh, 14 layers of mesh in all, and Max capacity of 0.4L), and I never had a bit of buildup again.

Funny enough, after doing this, I found that the blower started spooling quicker, making a noticeable amount more torque and reaching peak boost (14psi) about 575-625rpms sooner, the AFR variance was about half what it was prior, intake charge (oversized dual pass FMIC with both electric pull fansto pprevent heat soak, and 8-nozzle fine mist water/methanol IC sprayer) dropped 12-19F under boost and a bit more at idle, and throttle response was markedly improved.

I am confident that some of that was from the removal and replacement of junked PCV parts, and the installation of a 10x better and more efficient catch can (it was designed so that when full, it didn't completely block return air, instead it had a suction valve that would allow a small amount of the collected oil back into the sump).
Still, I would never want to have a caked up impeller; the potential hot spots will likely end up causing more problems than some SeaFoam and a toothbrush.

+1 a catch can is the answer, not "leave er' alone!". It may be a coincidence, but every engine i have ever messed with in a junkyard looked like that first photo.

 

[ls1mike]

Leave it alone. 3rd supercharged 3800 here. That is fine and won't get worse. Don't introduce chemicals into the blower.

This is carbon build up.

02 Jetta TDI 42,000 milles.

 

[Clevy]

Originally Posted By: ls1mike
Leave it alone. 3rd supercharged 3800 here. That is fine and won't get worse. Don't introduce chemicals into the blower.

This is carbon build up.

02 Jetta TDI 42,000 milles.


Wow. That's some serious deposits.
I agree about avoiding spraying anything into the airstream. The rotor may not agree with the addition.

 

[Artem]

I clean the DBW throttle body on my 06 Scion tC on a regular basis (every 25k or so whenever I service the air filter) it idles a lot smoother after the TB is clean.

I spray carb cleaner on a rag and go to town on it.

 

[sciphi]

Originally Posted By: SOHCman

+1 a catch can is the answer, not "leave er' alone!". It may be a coincidence, but every engine i have ever messed with in a junkyard looked like that first photo.


Not on this engine. The PCV system has no place to install one. It's routed internally through the engine block and intake manifold/supercharger housing.

 

[SOHCman]

Originally Posted By: sciphi
Originally Posted By: SOHCman

+1 a catch can is the answer, not "leave er' alone!". It may be a coincidence, but every engine i have ever messed with in a junkyard looked like that first photo.


Not on this engine. The PCV system has no place to install one. It's routed internally through the engine block and intake manifold/supercharger housing.


Interesting, I suppose I would still manually clean it if it were mine, using no chemicals if neccesary to avoide that fear of rotor damage. Afterall, it didnt come from the factory full of carbon.