Carbon Deposits on Intake Valves - Page 3 - Saturn Sky Forums: Saturn Sky Forum
Technical Saturn Sky Discussion Technical and performance aspects of the Saturn Sky Roadster. Sky Problems | Solutions | Repairs | Recalls | Tech Bulletins | Tech Tips | In the Manual Basic Tech Advertisement

User Tag List

LinkBack Thread Tools Display Modes
post #31 of 31 (permalink) Old 05-10-2018, 11:34 AM
Senior Member
SARBlade's Avatar
Join Date: Sep 2014
Location: Vancouver Island
Posts: 217
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 24 Post(s)
Originally Posted by syjos View Post
The carbon that build up on the valves is very hard. When CRC, Seafoam or some other carbon deposit remover is sprayed on the valves, it has to remain on the valves for a while and allow it to soak for it to work.

Spraying it into the manifold while the engine is running will not allow the CRC to soak effectively. And it certainly will not soften the carbon enough to dissolve it. What it does is cause some of the carbon to come off in chunks and flow into the cylinder and out the exhaust port. I would not want the hard chunks in my cylinder, on my piston rings, and certainly not through the turbo.

Before the naysayers chime in, I'll tell you about the carbon that I removed from a DI engine using CRC last year. No, I did not stupidly spray it into a running engine.

I took the intake manifold off, masked off the rest of the engine compartment with only the valve ports uncovered. I turned the engine so the intake valves were closed on one cylinder. I taped off the other ports and sprayed CRC on the valve stem, back of valves, port walls and let it soak about 30 minutes. I sprayed CRC on the valves from time to time to keep the valves wet. After 30 minutes, I scraped the carbon with a dental pick and pieces of carbon flaked off in 1/8" to 1/16" pieces. I felt the removed carbon and they were very hard and sharp. There was no soft/melted carbon residue. I was able to remove about 50% of the carbon with the pick and sprayed more CRC on the valves. I picked the rest of the carbon off but the valves were still not completely clean. I chucked a brass wire brush, the kind used for cleaning gun barrels, into a drill and used that at medium speed to clean the rest of the carbon off. Used a shop vacuum to remove CRC and carbon bits, flushed with more CRC until clean. The first cylinder took about 1 1/2 hours and when completed, the valves and port were completely clean.

I turned the engine so the valves on the next cylinder were closed and proceeded to clean that one. The second cylinder only took an hour. Used the wire brush more and at a faster speed. Did all four valves in one day. The engine had 36,000 miles on it, no catch can.

When I eventually clean the valves on the GXP, I may switch to walnut blasting, if a port adapter becomes available for these engines. Without a properly fitting port adapter, the walnut shells most likely will create a mess. I walnut blasted a DI diesel engine using a thick, stiff hose with similar diameter to the valve ports but the media would blow out of the edges. Whatever is used has to be the same shape as the port to make a tight fit. And it would be ideal if it could be bolted to the head using the manifold fastenings. Possibly cut up an intake manifold and use the individual runners for each port.
I used the CRC valve cleaning product as well but only after I walnut blasted. I did this as I couldn't really get everything with the media blasting blindly doing it. I sprayed CRC on, let it soak, then used a toothbrush to brush off. A rag stuffed in there to soak up any product left over. I also used a piece of pool hose for a valve intake channel adapter. It worked very well and very little walnut shell was thrown. See my pictures here.
syjos likes this.

2008 Sky Redline
Tarnished Silver Metallic
Trifecta Tuned
10mm 6061T Tunnel Brace
Seat Heaters
Universal Garage Remote
SARBlade is offline  
Sponsored Links

  Saturn Sky Forums: Saturn Sky Forum > Saturn Sky Discussion > Technical Saturn Sky Discussion

Quick Reply

Register Now

In order to be able to post messages on the Saturn Sky Forums: Saturn Sky Forum forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On

For the best viewing experience please update your browser to Google Chrome