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How do you clean combustion chambers?

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Old 05-22-2019, 11:21 AM
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How do you clean combustion chambers?

Hi,


Recently, I did a combustion chambers clean procedure. I added 1 can of ACDelco Combustion Chamber Cleaner directly to throttle body with hot engine @ 3.000 RPMs.

Engine runs great now, but I'm confused: the exhaust threw out zero smoke during the procedure. I did not see anything from my position in front of engine.

Maybe previous owner did the same, maybe the engine was clean (120.000 miles), I don't know.


Any ideas?


Thanks,

Denis V.

Old 05-22-2019, 08:43 PM
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Re: How do you clean combustion chambers?

Just a guess but maybe its because you ran the engine too fast. I read that you need to run it 300rpm over idle. So about 1000rpm.
Old 05-23-2019, 04:33 PM
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Re: How do you clean combustion chambers?

O.K, thanks, but high RPMs was used in order to avoid an hydrolocking risk or failure (according to my previous research and investigation)

Unfortunately, the ACdelco can instructions procedure is too incomplete. It don't says nothing about RPMs and if its speed must be going up and down or flat during the process.

You tube has only one video for this AcDelco product. It says: "up to 750 - 3000 RPMs". What it means?


Denis V.
Old 05-23-2019, 06:04 PM
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Re: How do you clean combustion chambers?

I used this stuff:

https://gumout.com/multi-system-tune-up/

I used two bottles. One, idling and fed into the power brake booster vacuum hose, followed by a quick shutoff and soak overnight and then a bottle in the full tank. I poured it in slowly over ten minutes or so (IIRC) and the car really "smoked up".

The P.E.A. molecule is supposed to be excellent at soaking and loosening carbon deposits.
Old 05-23-2019, 06:07 PM
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Re: How do you clean combustion chambers?

Originally Posted by Denis.V
O.K, thanks, but high RPMs was used in order to avoid an hydrolocking risk or failure (according to my previous research and investigation)

Unfortunately, the ACdelco can instructions procedure is too incomplete. It don't says nothing about RPMs and if its speed must be going up and down or flat during the process.

You tube has only one video for this AcDelco product. It says: "up to 750 - 3000 RPMs". What it means?


Denis V.
https://acdelco.com.au/our-range/che...stion-cleaner/
Application instructions in the specs pdf.
Old 05-23-2019, 08:03 PM
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Re: How do you clean combustion chambers?

I've used dihydrogen monoxide carefully applied to a hot and running engine through a vacuum port where it can be equally distributed to all cylinders.

You have to be careful with that stuff, however, since improper use of it has killed thousands of people;..
Old 05-23-2019, 08:13 PM
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Re: How do you clean combustion chambers?

Originally Posted by Denis.V
... the exhaust threw out zero smoke during the procedure. I did not see anything from my position in front of engine.
Any ideas?
Ideas? Yes. If you are getting fuel blended in Brazil with 22% ethanol content, there probably wasn't much excess carbon and contamination in the chambers to begin with. It may not produce the most power, but it does control detonation and keeps things relatively clean.
Old 05-24-2019, 03:44 AM
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Re: How do you clean combustion chambers?

I pull the spark plugs and using a thin plastic tube, attached to a funnel, pour 1/8 of a can of Seafoam, into each cylinder. After an overnight sit, I crank the engine, to expel any fluid, install the plugs, start it and drive it hard (nothing stupid) for a few miles. I also sometimes add a can of Seafoam, slowly into the intake, of a high idling engine. I have also done this w/ water.
Old 05-24-2019, 11:14 AM
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Re: How do you clean combustion chambers?

Seafoam. They make a can now that is pressurized with a long spray nozzle for spraying into a running engine. Plus you can dump a can into the tank.

Last time I did something like this I dumped a can of Seafoam in the tank and a bottle of the Gumout Regaine (with PEA) fuel system cleaner. Both at the same time.
Old 05-24-2019, 12:05 PM
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Re: How do you clean combustion chambers?

I want to add a few data:

In the 6 months prior to cleaning the combustion chambers, I added to fuel tank around 5 cans of LIQUI MOLY (made in Germany) Fuel Injectors Cleaner. This is the most expensive cleaner, but is an injectors cleaner, not a combustion chambers cleaner.
They could have cleaned something too.

When I completed my combustion chamber cleaning process, I replaced the oil, because, according to my previous search, the cleaner wash the cylinders walls and could contaminate the engine oil.


Denis V.




Old 05-24-2019, 12:05 PM
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Re: How do you clean combustion chambers?

The only time this is a problem (dirty combustion chambers) is:

1. Car has been driven by grandma like it's in a parade.

2. Engine burns copious amounts of oil.

The fix for #1 is to drive the car harder and get the combustion temps and exhaust temps up to burn all that crap out.

The fix for #2 isn't going to be found at the bottom of mechanic in a can.

You are throwing additives in it like crazy and this really isn't a permanent solution.

Lets back way, way up here. What is the PROBLEM you are trying to solve? If there is no problem then STOP screwing with it.

GD

Last edited by GeneralDisorder; 05-24-2019 at 01:15 PM.
Old 05-24-2019, 12:27 PM
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Re: How do you clean combustion chambers?

Originally Posted by Vader
I've used dihydrogen monoxide carefully applied to a hot and running engine through a vacuum port where it can be equally distributed to all cylinders.

You have to be careful with that stuff, however, since improper use of it has killed thousands of people;..
Everyone that drinks it dies eventually...
Old 05-24-2019, 08:35 PM
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Re: How do you clean combustion chambers?

dihydrogen monoxide



Don't you know that the state of California has declared that substance as a hazard to health? It has been conclusively proven that laboratory rats cannot survive immersion in a pure environment of that stuff for more than 45 seconds or so. Death occurs in statistically indistinguishable from 100% of such instances. Very dangerous.

I wouldn't let it in my house, let alone pour it into any part of my car.

Don't even get me started on vacuum.
Old 05-25-2019, 08:53 AM
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Re: How do you clean combustion chambers?

Originally Posted by sofakingdom
...Don't even get me started on vacuum.
Yes, a nearly complete absence of molecules at a practically undetectable pressure really sucks.
Old 05-28-2019, 01:11 PM
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Re: How do you clean combustion chambers?

How bad is it? Have you put a borescope in the spark plug holes and looked inside the cylinders?
Old 05-30-2019, 02:39 PM
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Re: How do you clean combustion chambers?

Borescope?. Great great idea. Thanks!



Denis V.
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