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Best carbon cleaner for the 4.0?

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mattyice2

mattyice2

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What are you trying to de-carbon? Do you believe it to be carboned up by having driven it too conservatively?

Not sure probably everything. Scotty Kilmer is most concerned about carbon on the intake system. I drive mine pretty regularly, but I've heard that carbon buildup can be bad for an engine. My biggest concern would be a carbon buildup that causes pre-ignition problems. Mine has 180,000 miles on it.
 
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Jerry Bransford

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@Jerry Bransford my TJ almost never gets above 3200 RPM , do you recommend a carbon cleaner or should i just start revving it higher occasionally? My TJ has 80k on it
Carbon build up in the combustion chambers is a common problem when you baby an engine too much like that. It can cause reduced performance, knocking, and/or pinging under acceleration.

It's time to do the old time-honored "Italian tuneup. When and where safe, start doing hard full throttle accelerations to high rpms, 4k and higher. It could take time to get it cleaned out, and don't be surprised if you see bits of black gunk blowing out the exhaust.

And when you can, start driving it more aggressively and stop babying the engine. It runs better when it sees higher rpms to keep things clean.

I learned about this from a Corvette mechanic. He said few customers drove their Corvettes aggressively enough and would bring them to the dealer complaining it wasn't running right. He would repeatedly rev them hard until they were running well again.

The reason engines start knocking or pinging when the combustion chambers load with carbon is because the carbon reduces the size of the combustion chamber which raises the combustion chamber pressure during the combustion stroke which prematurely ignites the fuel causing knocking or pinging... aka premature detonation.
 

HDRider

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What are you trying to de-carbon? Do you believe the combustion chambers to be carboned up by having driven it too conservatively?

I don't want to co-op this thread. Tell me if I should start an all new thread.

But let's say my answer is yes. If i put the gas to the floor. I am at 3200 RMPs when it hits high gear. It has an auto tranny.

Cruising at 70 I am at 2800 RMP.

Do I manually shift the trans and take her up to 4,000 every once in a while. Or, how close to redline do I need to go?

I have been running a heavy dose of Lucas in it since I got it about 2 months ago.
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Thanks
 

Rickyd

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A nice blown headgasket or trip through too deep of water will make those chambers look brand new! Results may vary...
 

Jerry Bransford

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I don't want to co-op this thread. Tell me if I should start an all new thread.

But let's say my answer is yes. If i put the gas to the floor. I am at 3200 RMPs when it hits high gear. It has an auto tranny.

Cruising at 70 I am at 2800 RMP.

Do I manually shift the trans and take her up to 4,000 every once in a while. Or, how close to redline do I need to go?

I have been running a heavy dose of Lucas in it since I got it about 2 months ago.
View attachment 346304

Thanks
Manually holding the transmission in gear until the engine reaches higher rpms works fine to help a carboned up engine. Injector and fuel system cleaners or "conditioners" won't help there at all.
 
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Jerry Bransford

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BlueC

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Techron, Cataclean or something else? Let the debate begin!

Seafoam.

Old timers used to dribble water into the carb, which effectively steam cleans the cylinders. It works, but I'm not a fan of water in my engine.
 

CharlesHS

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My experience is to add some Seafoam to the fuel tank before a long road trip which will slowly remove the carbon build up OR
Adding drips of water into throttlebody for several minutes as JB replied in Post #13.
 

Jerry Bransford

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Seafoam.

Old timers used to dribble water into the carb, which effectively steam cleans the cylinders. It works, but I'm not a fan of water in my engine.
Water in the engine when used like that absolutely will NOT harm the engine in any way. No way no how. In fact water injection has been used in internal combustion engines since at least the 1940's which is when it was discovered how clean the engines were internally with its use. It is still used, it's even used in some jet engines. Water is injected to add power to the engine.

We're not talking about dumping water into an engine that would cause hydrolock, we're talking about dribbling it in or spraying it in as a mist. Even Mopar's Combustion Chamber Cleaner used by dealerships is mostly water with a little ammonia added.
 
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BlueC

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Water in the engine when used like that absolutely will NOT harm the engine in any way. No way no how. In fact water injection has been used in internal combustion engines since at least the 1940's which is when it was discovered how clean the engines were internally with its use. It is still used, it's even used in some jet engines. Water is injected to add power to the engine.

I'm aware. I'm not saying it will kill or even hurt an engine in such a small quantity. I assume an engine consumes as much water driving in heavy rain. I'm just personally not a fan of doing it when there are petroleum based products available.

We're not talking about dumping water into an engine that would cause hydrolock

This is the scenario that keeps me from ever mentioning it, or anything like it, to someone who hasn't demonstrated mechanical knowledge to me. When people don't have a basic mechanical understanding, they're likely to just fuck things up in a hurry.

I've seen it before, as I'm sure you have. I had a guy see one of my engine bays and asked how I kept it clean. I said I wash it. A little later, I see him dump a 5 gal bucket of soapy water directly on his engine. He destroyed some control module in the process that cost him nearly $2k.