Where can I find the decarbonization procedure?
Thread Starter
Burning Brakes
Joined: Apr 1999
Posts: 1,150
Likes: 0
From: Saratoga CA
Where can I find the decarbonization procedure?
There was a procedure posted by one of our resident C5 tech specialists for decarbonization a few months ago. Maybe even half a year ago. I can't find it and the search is not working. Does anyone know where I can find it? Or can someone repost it?
Thanks!
99 C5 M6 :flag
Former Vendor
Joined: Apr 2001
Posts: 10,976
Likes: 21
From: FL
St. Jude Donor '13
Re: Where can I find the decarbonization procedure? (akw408)
Remove the spark plugs and pour some GM top engine cleaner (gooood stuff)in each cylinder.Let set overnite.Spin the motor over and reinstall the plugs...OR induce it into the cylinders through a vaccum source until it chokes and stalls the motor.Again,let set overnite.Ghange the oil after either procedure.
I removed the cylinder heads off a 1999 with 15k and you would not believe the amount of carbon buildup on top of the pistons :smash:
I removed the cylinder heads off a 1999 with 15k and you would not believe the amount of carbon buildup on top of the pistons :smash:
Thread Starter
Burning Brakes
Joined: Apr 1999
Posts: 1,150
Likes: 0
From: Saratoga CA
Re: Where can I find the decarbonization procedure? (C-5 TECH)
Thanks C5 TECH! Can you tell me where to get this good stuff? Is there a part number? And how much good stuff goes into each cylinder?
How do I spin the motor over? Just crank it with the starter motor?
I am considering doing this because I have noticed lately that when I shut down my car, I hear this sound, like snapping. It is infrequent, maybe once every 30 seconds and continues on for maybe 5 minutes tops. Could that sound be related to this problem? I want to be proactive and do something before it gets more serious (like once every 5 seconds). I should do the same thing on my other cars too.
99 C5 M6
Team Owner
Joined: Aug 2000
Posts: 24,103
Likes: 1,327
From: Spring Texas
Re: Where can I find the decarbonization procedure? (akw408)
I captured this a while ago.
Decarbonizing Engine
Okay, first thing, go down to your GM dealer and purchase 2 cans of liquid top engine cleaner #1050002. That’s the part number. And get oil and filter, as you will have to change the oil after this procedure.
Second, let the car sit until it gets cold before you start this procedure.
Now, are you ready???? First, remove all spark plugs.
Next, evenly divide the 2 cans to feed 8 cylinders.
Remember that this will get messy, so have plenty of rags around, and put something under your car, and not all the cylinders will take all the chemical.
Next, add the cleaner to each cylinder, some may pour out, and some may take all of it. I leave rags under each plug hole.
Then, pop a cold one because the cleaner must sit at least 6 hours, I like to see 12, but at least 6 is the minimum.
The next morning or whatever put a bunch of rags over all the plug holes, as you must crank over the engine to expel all the cleaner. It’s going to leave a mess, so be warned. Crank over then engine for about 15 seconds, that’s all it takes. Clean up all the residual off the manifolds, with brake cleaner or something. Install the plugs.
Roll the vehicle outside, cause MAN is this going to smoke, and stink. Start it up, it will run rough for a while, this is common, and it will smoke too. Allow to idle for 20 mins. Then shut the engine down, and change the oil and filter.
The cleaner dilutes the oil so we don’t want to drive the car until after all has been consumed in the chamber, and the oil is warm.
Ok, now for the test drive, go to a highway, and drive a highway speeds for about 20 mins, to expel the cleaner from the exhaust. The car WILL smoke for some of the test drive, this is NORMAL. But by the time that you get back, it should be pretty much gone.
Ok, that’s it. Just remember, this is informational, nothing more. You may get some oxygen codes or some misfire until the cleaner is burned off, this is NORMAL. Just reset the codes, and you will be fine.
Decarbonizing Engine
Okay, first thing, go down to your GM dealer and purchase 2 cans of liquid top engine cleaner #1050002. That’s the part number. And get oil and filter, as you will have to change the oil after this procedure.
Second, let the car sit until it gets cold before you start this procedure.
Now, are you ready???? First, remove all spark plugs.
Next, evenly divide the 2 cans to feed 8 cylinders.
Remember that this will get messy, so have plenty of rags around, and put something under your car, and not all the cylinders will take all the chemical.
Next, add the cleaner to each cylinder, some may pour out, and some may take all of it. I leave rags under each plug hole.
Then, pop a cold one because the cleaner must sit at least 6 hours, I like to see 12, but at least 6 is the minimum.
The next morning or whatever put a bunch of rags over all the plug holes, as you must crank over the engine to expel all the cleaner. It’s going to leave a mess, so be warned. Crank over then engine for about 15 seconds, that’s all it takes. Clean up all the residual off the manifolds, with brake cleaner or something. Install the plugs.
Roll the vehicle outside, cause MAN is this going to smoke, and stink. Start it up, it will run rough for a while, this is common, and it will smoke too. Allow to idle for 20 mins. Then shut the engine down, and change the oil and filter.
The cleaner dilutes the oil so we don’t want to drive the car until after all has been consumed in the chamber, and the oil is warm.
Ok, now for the test drive, go to a highway, and drive a highway speeds for about 20 mins, to expel the cleaner from the exhaust. The car WILL smoke for some of the test drive, this is NORMAL. But by the time that you get back, it should be pretty much gone.
Ok, that’s it. Just remember, this is informational, nothing more. You may get some oxygen codes or some misfire until the cleaner is burned off, this is NORMAL. Just reset the codes, and you will be fine.
Team Owner
Joined: Jun 2001
Posts: 100,672
Likes: 2
From: Cleveland OH
Re: Where can I find the decarbonization procedure? (CP)
Again I will ask... "Crank over the Engine" what does that exactly mean... and when is this process best to do, mileage..?
:cheers: :confused: :confused: :confused:
:cheers: :confused: :confused: :confused:
Pro
Joined: Apr 2000
Posts: 701
Likes: 1
From: Nashville, TN
Re: Where can I find the decarbonization procedure? (C-5 TECH)
Remove the spark plugs and pour some GM top engine cleaner (gooood stuff)in each cylinder.Let set overnite.Spin the motor over and reinstall the plugs...OR induce it into the cylinders through a vaccum source until it chokes and stalls the motor.Again,let set overnite.Ghange the oil after either procedure.
ShoPig
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Melting Slicks
Joined: Aug 2000
Posts: 2,248
Likes: 1
From: Newland US
Re: Where can I find the decarbonization procedure? (ShoPig)
I would like to hear more details about the "induce it into the cylinders through a vacuum source" method. This sounds easier and less messy. But, do you still have to pull the plugs when you turn over the engine to blow out the cleaner after sitting overnight? And, does this method work as well as pouring the cleaner into the spark plug holes?
ShoPig
ShoPig
You can disconnect the brake booster hose on most cars and allow the vacuum to pull the cleaner in through that hose.
No, the plugs don't have to be removed.
There used to be a GM top end cleaner and the directions on the can indicated to introduce some water first (slowly) so as not to kill the engine....and then introduce the top end cleaner, finally pouring in enough to kill the engine as C5-TECH said in his post. Then you were to let it sit 8 hours, start it up (yep, she'll smoke) and run for about 20 minutes.
Either way you MUST change the oil and filter after the treatment, because some of the cleaner will find its way past the rings and into the crankcase and it will be caustic to the inserts in the rods and mains.
I've used this method with good results.
Good luck.
Mark
Safety Car
Joined: Jan 2000
Posts: 4,965
Likes: 0
From: Midlothian, VA
Re: Where can I find the decarbonization procedure? (MDT)
There used to be a GM top end cleaner and the directions on the can indicated to introduce some water first (slowly) so as not to kill the engine....and then introduce the top end cleaner, finally pouring in enough to kill the engine as C5-TECH said in his post. Then you were to let it sit 8 hours, start it up (yep, she'll smoke) and run for about 20 minutes.
Either way you MUST change the oil and filter after the treatment, because some of the cleaner will find its way past the rings and into the crankcase and it will be caustic to the inserts in the rods and mains.
I've used this method with good results.
Good luck.
Mark
Either way you MUST change the oil and filter after the treatment, because some of the cleaner will find its way past the rings and into the crankcase and it will be caustic to the inserts in the rods and mains.
I've used this method with good results.
Good luck.
Mark
Melting Slicks
Joined: Aug 2000
Posts: 2,248
Likes: 1
From: Newland US
Re: Where can I find the decarbonization procedure? (C5Noir)
You can pour water in initially???? :confused:
Yes you can. The old timers have used this for years. The steam helps soften the carbon. Have you ever looked at a spark plug removed from a cylinder that had a leaky head gasket allowing coolant into the cylinder? The plug will be spanking clean compared to the others.
Good luck.
Mark
Good luck.
Mark
Melting Slicks
Joined: Mar 2001
Posts: 2,809
Likes: 0
From: Frisco TX
Re: Where can I find the decarbonization procedure? (akw408)
I felt it necessary to fill you all in on how to decarbon your engines. Here is the reason. For most all situations, knock on a stock c5 will be due to carbon buildup, plain and simple. While there is a lot of speculation, fact is that out of 51 different c5 that I have performed this procedure, NONE have returned. There will always be the occasional one that this may NOT apply to, but for the most part, it should work. Also, just a side note, if your c5 is modified, even with just a MAF, this may not work, due to other issues, so do not ASSUME that this is a fix all.
Okay, first thing, go down to your GM dealer and purchase 2 cans of liquid top engine cleaner #1050002. That’s the part number. And get oil and filter, as you will have to change the oil after this procedure.
Second, let the car sit until it gets cold before you start this procedure.
Now, are you ready???? First, remove all spark plugs.
Next, evenly divide the 2 cans to feed 8 cylinders.
Remember that this will get messy, so have plenty of rags around, and put something under your car, and not all the cylinders will take all the chemical.
Next, add the cleaner to each cylinder, some may pour out, and some may take all of it. I leave rags under each plughole.
Then, pop a cold one because the cleaner must sit at least 6 hours, I like to see 12, but at least 6 are the minimum.
The next morning or whatever put a bunch of rags over all the plugholes, as you must crank over the engine to expel the entire cleaner. It’s going to leave a mess, so be warned. Crank over then engine for about 15 seconds, that’s all it takes. Clean up all the residual off the manifolds, with brake cleaner or something. Install the plugs.
Roll the vehicle outside, cause MAN is this going to smoke, and stink. Start it up, it will run rough for a while, this is common, and it will smoke too. Allow to idle for 20 mins. Then shut the engine down, and change the oil and filter.
The cleaner dilutes the oil so we don’t want to drive the car until after all has been consumed in the chamber, and the oil is warm.
Ok, now for the test drive, go to a highway, and drive a highway speeds for about 20 mins, to expel the cleaner from the exhaust. The car WILL smoke for some of the test drive, this is NORMAL. But by the time that you get back, it should be pretty much gone.
Ok, that’s it. Just remember, this is informational, nothing more. You may get some oxygen codes or some misfire until the cleaner is burned off, this is NORMAL. Just reset the codes, and you will be fine.
I have had a lot of success with this, as have some of the members that I have emailed this process to, but you must follow it exactly, thanks.
Best to all, and I remain, c4c5 specialist
------------------
c4c5mechanic, GM certified in all areas. ASE master certification w/L1. Club Corvette of CT member.
Okay, first thing, go down to your GM dealer and purchase 2 cans of liquid top engine cleaner #1050002. That’s the part number. And get oil and filter, as you will have to change the oil after this procedure.
Second, let the car sit until it gets cold before you start this procedure.
Now, are you ready???? First, remove all spark plugs.
Next, evenly divide the 2 cans to feed 8 cylinders.
Remember that this will get messy, so have plenty of rags around, and put something under your car, and not all the cylinders will take all the chemical.
Next, add the cleaner to each cylinder, some may pour out, and some may take all of it. I leave rags under each plughole.
Then, pop a cold one because the cleaner must sit at least 6 hours, I like to see 12, but at least 6 are the minimum.
The next morning or whatever put a bunch of rags over all the plugholes, as you must crank over the engine to expel the entire cleaner. It’s going to leave a mess, so be warned. Crank over then engine for about 15 seconds, that’s all it takes. Clean up all the residual off the manifolds, with brake cleaner or something. Install the plugs.
Roll the vehicle outside, cause MAN is this going to smoke, and stink. Start it up, it will run rough for a while, this is common, and it will smoke too. Allow to idle for 20 mins. Then shut the engine down, and change the oil and filter.
The cleaner dilutes the oil so we don’t want to drive the car until after all has been consumed in the chamber, and the oil is warm.
Ok, now for the test drive, go to a highway, and drive a highway speeds for about 20 mins, to expel the cleaner from the exhaust. The car WILL smoke for some of the test drive, this is NORMAL. But by the time that you get back, it should be pretty much gone.
Ok, that’s it. Just remember, this is informational, nothing more. You may get some oxygen codes or some misfire until the cleaner is burned off, this is NORMAL. Just reset the codes, and you will be fine.
I have had a lot of success with this, as have some of the members that I have emailed this process to, but you must follow it exactly, thanks.
Best to all, and I remain, c4c5 specialist
------------------
c4c5mechanic, GM certified in all areas. ASE master certification w/L1. Club Corvette of CT member.
Drifting
Joined: May 1999
Posts: 1,795
Likes: 1
From: Chicago IL
Re: Where can I find the decarbonization procedure? (MDT)
My dealer told me that GM just released some statement that dealers are no longer doing decarbonization as this is a quick fix (only good for about 2K miles) and that carbon would soon build up again. Evidently they are working on coating the pistons to minimize buildup. Is this accurate? Seems like a pretty extensive procedure for a short term fix...
Le Mans Master
Joined: Sep 2000
Posts: 5,027
Likes: 320
From: N. CA
Re: Where can I find the decarbonization procedure? (sbkim)
From an earlier post:
"Great info c4c5specialist! I do have a little concern although, it seems to me that somewhere in this procedure you should either remove the power to the ign. coils or remove the power from the injectors because when you crank the engine over and you have a ignition source very close to the spark plug holes and at the same time the injectors are being pulsed to spray fuel (this is blasting out of the spark plug holes as you are cranking) this has the potential for disaster I actually saw this happen and it ended being a hell of a fire! anyway just a thought."
"Your absolutely right, I am sorry that I did not remember to put that in, you are very right in disconnecting the coil pack wiring harness located at the center of the valve cover, and thanks for pointing that out. Very important SAFTY tip.Mean, the only real way to tell is with Autotap or a TECH2 scan tool. Unfortunately, you cant really tell otherwise.Lyonsh, I dont know about the chemical of what you speak, I, personally cannot vouch for if it works or not, or the application method. The only thing that I do know, is that you are looking for penetration of the carbon build up at the first ringland on the sides of the pistons, that is the cause for most of the noise concerns, not so much the knock issue itself. That is why we let it sit overnight.Best to all, and if your mechanic has a prefered chemical, it very well could work, I remain, c4c5"
[Modified by BOBSZ06, 7:01 AM 10/5/2001]
"Great info c4c5specialist! I do have a little concern although, it seems to me that somewhere in this procedure you should either remove the power to the ign. coils or remove the power from the injectors because when you crank the engine over and you have a ignition source very close to the spark plug holes and at the same time the injectors are being pulsed to spray fuel (this is blasting out of the spark plug holes as you are cranking) this has the potential for disaster I actually saw this happen and it ended being a hell of a fire! anyway just a thought."
"Your absolutely right, I am sorry that I did not remember to put that in, you are very right in disconnecting the coil pack wiring harness located at the center of the valve cover, and thanks for pointing that out. Very important SAFTY tip.Mean, the only real way to tell is with Autotap or a TECH2 scan tool. Unfortunately, you cant really tell otherwise.Lyonsh, I dont know about the chemical of what you speak, I, personally cannot vouch for if it works or not, or the application method. The only thing that I do know, is that you are looking for penetration of the carbon build up at the first ringland on the sides of the pistons, that is the cause for most of the noise concerns, not so much the knock issue itself. That is why we let it sit overnight.Best to all, and if your mechanic has a prefered chemical, it very well could work, I remain, c4c5"
[Modified by BOBSZ06, 7:01 AM 10/5/2001]
