How to clean carbon on valves? - Page 2
  1. Welcome to RangeRovers.net – General discussion forum for Range Rovers

    Welcome to RangeRovers.net - a website dedicated to all things Range Rovers.

    You are currently viewing our forum as a guest, which gives you limited access to view most discussions and access our other features. By joining our community, at no cost, you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is free, fast and simple, Join RangeRovers.net today!
     
+ Reply to Thread
Page 2 of 2 FirstFirst 1 2
Results 16 to 20 of 20

Thread: How to clean carbon on valves?

  1. #16
    FRESHMAN ROVER
    Join Date
    March 10th, 2019
    Location
    Holmdel, NJ
    Posts
    41

    Re: How to clean carbon on valves?

    CDOCKSEY, you do missing the point. The carbon build up is on the inner side of the valve, the side facing the intake not a combustion chamber.
    Dear OP- Knalex01, would you please post some pictures of contaminated valves. It should help the crowd to get a better understanding. If you really want have the understanding of the issue, type "GDI engine issue" in Youtube. Articles are plentiful and very educational.
    2013 RRS SC, Fuji White with Almond/Mocha int. 80K ml

  2. Remove Advertisements
    Range Rovers Forum
    Advertisements
     

  3. #17
    SOPHOMORE ROVER
    Join Date
    July 21st, 2011
    Location
    Virginia Beach, VA
    Posts
    466

    Re: How to clean carbon on valves?

    That is correct. The carbon build up is on the air intake side of the valves, not the combustion chamber/injection side. I think that the Engineering firm's answer is wrong for this problem. The CRC solution would clean off most of the carbon buildup on the valve stems without ever effecting the pistons or rings. The walnut dust solution would work, but I am concerned about how that would spatter the top of the piston and underside (combustion side) of the valves as some of the dust would surely bleed through at start up (unless you have an incredibly strong vacuum cleaner). When I had it done on a BMW (325IS), it was not with a direct injection mill; worked well, cost too much for what little gain I saw at WOT.

    I think you could get the same results by washing the stems with the CRC solution before reinstalling the manifold and SC. You have the system open for observation; spray it, bottle brush the stems; close it up and see if it runs better. The stuff will dry before you are done.
    Cheers, Jim

    2017 Lincoln Continental Select 2.7 AWD; 2013 RRSport HSE, 40000 miles (traded); 2001 Jaguar XJ8L X308 BRG 89000 miles (traded on RRS); 08 RRSport SC (sold); 08 LR 3 (traded); 05 LR 3 4.2 (traded); 04 BMW Z4 sold; 01 XJ8 anthracite (for LR 3); 98 Z3 (traded on Z4); 01 S-type 4.0 V8 (traded on XJ8; 99 323 IC (traded on S-type); 94 Deville traded; 88 325IS sold

  4. #18
    FRESHMAN ROVER
    Join Date
    January 28th, 2012
    Location
    Venezuela
    Posts
    22

    Re: How to clean carbon on valves?

    Oh Oh... definately the air intake side... I am talking exactly about that....
    Ok, lets see...... there are 2 carbon build ups that can prevent a good "seal", or proper valve closure.
    1) the dirt/dust form of carbon etc on the valve stem, which avoids good sliding within the guide and sometimes hinders the valve from fully closing. Here is where we discuss whether CRC, brushes and walnut blasting etc may help....
    2) the carbon build up on that same side of the valve, but on the edge..... on the chamfer edge which is where it seats perfectly to "seal" when closed. If there is irregular carbon build up on that chamfered border, then you will have a leak. This is where I don't see how you can clean this with walnut blasting.... or CRC either. If valve is closed, the walnut won't get to it, and if open, all the blasting will enter the combustion chamber which you don't want...
    Now... if we could find a way to clean that chamfered edge by "rubbing"it with CRC somehow, then we might have something. All depends how "quick acting" the CRC is.

    Sent from my SM-G950U1 using Tapatalk
    2006 4.2 Supercharged Full Size Range Rover
    Zambezi Silver/Jet black

  5. Remove Advertisements
    Range Rovers Forum
    Advertisements
     

  6. #19
    FRESHMAN ROVER
    Join Date
    April 22nd, 2019
    Location
    Bowling Green, KY
    Posts
    50

    Re: How to clean carbon on valves?

    Quote Originally Posted by Roman NJ View Post
    CDOCKSEY, you do missing the point. The carbon build up is on the inner side of the valve, the side facing the intake not a combustion chamber.
    Dear OP- Knalex01, would you please post some pictures of contaminated valves. It should help the crowd to get a better understanding. If you really want have the understanding of the issue, type "GDI engine issue" in Youtube. Articles are plentiful and very educational.
    Ask and ye shall receive. Took these yesterday. The quality is not terrific - these are taken with an endoscope that I bought off amazon that connects to your cell phone. I bought it so I could make absolutely sure the valves are closed and it works well.

    Note the "crystalline" nature of the carbon (you can see it is shiny and reflects light), which is exactly how the engineering firm I mentioned earlier described this stuff. It's rock hard, there is no way in hell a chemical cleaner would get this stuff off, at least not in any reasonable amount of time.

    How to clean carbon on valves?-1.jpg

    How to clean carbon on valves?-2.jpg

    How to clean carbon on valves?-3.jpg
    2012 Range Sport Autobiography Supercharged, Fuji White, 72K

  7. #20
    FRESHMAN ROVER
    Join Date
    April 22nd, 2019
    Location
    Bowling Green, KY
    Posts
    50

    Re: How to clean carbon on valves?

    Quote Originally Posted by cdocksey View Post
    Oh Oh... definately the air intake side... I am talking exactly about that....
    Ok, lets see...... there are 2 carbon build ups that can prevent a good "seal", or proper valve closure.
    1) the dirt/dust form of carbon etc on the valve stem, which avoids good sliding within the guide and sometimes hinders the valve from fully closing. Here is where we discuss whether CRC, brushes and walnut blasting etc may help....
    2) the carbon build up on that same side of the valve, but on the edge..... on the chamfer edge which is where it seats perfectly to "seal" when closed. If there is irregular carbon build up on that chamfered border, then you will have a leak. This is where I don't see how you can clean this with walnut blasting.... or CRC either. If valve is closed, the walnut won't get to it, and if open, all the blasting will enter the combustion chamber which you don't want...
    Now... if we could find a way to clean that chamfered edge by "rubbing"it with CRC somehow, then we might have something. All depends how "quick acting" the CRC is.

    Sent from my SM-G950U1 using Tapatalk
    Valve seal is not the issue, smooth airflow is the issue.
    2012 Range Sport Autobiography Supercharged, Fuji White, 72K

+ Reply to Thread
Page 2 of 2 FirstFirst 1 2

Quick Reply Quick Reply

Register Now

Similar Threads

  1. Has anyone used Seafoam to clean the carbon build up in the 5.0 SC
    By 98cruiser in forum Range Rover Sport / L320
    Replies: 11
    Last Post: October 8th, 2015, 11:59 AM
  2. Gen III Airbag valves
    By Jsmooth65 in forum Range Rover Mark II / P38
    Replies: 5
    Last Post: December 5th, 2007, 08:14 AM
  3. EAS: Non return Valves, where to get ?
    By jesusg9 in forum Range Rover Mark II / P38
    Replies: 9
    Last Post: November 29th, 2007, 08:42 AM
  4. Do all check valves face same way on valve block rebuild?
    By kmagnuss in forum Range Rover Mark II / P38
    Replies: 4
    Last Post: February 11th, 2007, 03:23 PM
  5. Sticking Exhaust Valves
    By rtkraken in forum Range Rover Mark II / P38
    Replies: 4
    Last Post: July 30th, 2006, 03:01 PM

Tags for this Thread

Posting Permissions

  • You may post new threads
  • You may post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Powered by vBadvanced CMPS v4.3.0