Water decarbonization methods

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Drew99GT

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I'm thinking of trying this on my Corolla; I recently used Techron and Seafoam through the PCV hose with fairly dramatic positive results. However, upon installing new spark plugs, I can clearly see the piston tops still have what looks like a soft/oily/shiny looking deposit layer. The car still has a very slight ping under hard acceleration that has mostly been solved with the Techron/Seafoam, so I thought I'd try the water decarb method for the heck of it. I was planning to do it through the PCV line since it looks like it evenly feeds all 4 cylinders. However, I read a few posts where people had problems messing up the MAP or other sensors using a vacuum line to feed water in. Is this really a problem? Has anyone successfully used the PCV line to do a water decarb, or should I just spray directly into the throttle body? I'm planning to use a spray bottle with hot water with the engine hot and running at 1500 rpms.

Thanks
 
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Did you not first try Techron through the gas tank?

If not, was there a reason not to?

That is usually enough to do the cleaning required.
 
I use a sports water bottle with the pull out nipple....so it has a nice/fat stream of water.

I've had great results doing this on my truck. Bump the RPM's around 2500 and feed her the water until it stumbles, and then back off, and then feed her some more water. Do that until you give her a gallon. If it's really carboned up, it could take more. Give her water until the exhaust doesn't smell like burnt gunpowder.

You should notice a "burnt firecracker" smell coming out your tail pipe. That's carbon.
 
I use a garden sprayer like this one. Remove the intake tube and have at it.

Only thing I'm concerned about is water falling out and getting stuck on the bottom of the intake manifold. I rev it pretty high before letting the clutch out so there are many rev's to spread that water droplet over.
 
The head gasket on my Camry went out,allowing water into cylinder.Man, you could eat off those piston tops,that"s how clean they were!
 
Back in the day, I went to the model supply store, and bout some 1/2" brass tube, and some 1/6" IIRC, and soldered a "tee" together that would fit into th PCV line.

Then soldered another barb onto a peach can.

Joined the two with aquarium hose and needled valve.

Filled peach can with ATF, then dribbled through the PVC (no cats back then).

After that, would run 1-2L of water through it. Open the needle valve until you have a borderline "stumble" and let it run.

I used the tee then to drip feed Lucas through it with an oiler.
 
I know a man who tees off from the brake booster (2" additional booster vacuum line, a tee and reducer), using a very small line like what you would find on a mechanical oil gauge, runs it in to the passenger compartment putting the end in a gallon of water, 10% antifreeeze mix. He slightly attenuates the flow as to not effect braking. He then heads off on a long trip after about 35 miles of freeway driving the gallon is empty. I tried this myself with a quart of water fearing I would overdo it or hydrostatically lock the engine and had great results verified by an HD borescope. I did this right before an oil change. I also brought along a cap for the ride to cap the line once the water was sucked out.
In the end I had clean pistons and valves but still had to remove the intake manifold to replace the knock sensor.
 
Originally Posted By: eljefino
I use a garden sprayer like this one. Remove the intake tube and have at it.

Only thing I'm concerned about is water falling out and getting stuck on the bottom of the intake manifold. I rev it pretty high before letting the clutch out so there are many rev's to spread that water droplet over.


I had always wanted to try it with my Hudson garden sprayer as well. Adjust the nozzle for a medium (?) fine spray and poke it through the throttle body blade and pull the trigger.
 
Originally Posted By: Drew99GT
I'm thinking of trying this on my Corolla; I recently used Techron and Seafoam through the PCV hose with fairly dramatic positive results. However, upon installing new spark plugs, I can clearly see the piston tops still have what looks like a soft/oily/shiny looking deposit layer. The car still has a very slight ping under hard acceleration that has mostly been solved with the Techron/Seafoam, so I thought I'd try the water decarb method for the heck of it. I was planning to do it through the PCV line since it looks like it evenly feeds all 4 cylinders. However, I read a few posts where people had problems messing up the MAP or other sensors using a vacuum line to feed water in. Is this really a problem? Has anyone successfully used the PCV line to do a water decarb, or should I just spray directly into the throttle body? I'm planning to use a spray bottle with hot water with the engine hot and running at 1500 rpms.

Thanks


I used a basketball needle on a hose connected where the PVC hose attaches to the intake. Suck up hot water through the needle slowly. The problem is you have to get the engine hot before you do this. And then go for a long ride after to burn off an water that made it into the oil. This is a lot of work and a lot of room for error.

If you want the piston tops clean do a MMO piston soak. It works, let it soak of at least a day and top up as needed. I posted a picture here where I can make out the letter "B" on the piston top because it was so clean.
 
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Well, I did the water decarb procedure. I sprayed a full bottle of hot water through the PCV line. I have to say, this car suffers from deposits fairly bad because of oil consumption and oil getting pulled through the PCV line. I have never done anything that made this dramatic of an improvement in engine performance! It's had a slightly rough idle when it first warms up and it's gone now; the throttle response is like night and day better. The engine ping is gone. This will definitely be something I do for routine maintenance.
 
Oh, do you guys think an oil change is necessary after doing this? I would think not much if any water would make it past the rings and into the crankcase. Most of it probably evaporates during combustion and gets blown out the exhaust.
 
The water method is largely ineffective. Certainly, if you leave a cylinder full of a water/antifreeze mix, it will eventually soften the carbon. That's the reason head gasket failures leave clean combustion chambers.

This is 100% impractical in the real world. And pouring a cup, quart or gallon of water through the intake won't do much of anything. Other than some of it getting by the rings and into the oil.

I ran water injection 100% of the time on a car with 12.7 to 1 compression. Carbon buildup was normal and significant. Regardless of how much water went through the engine.
 
If not careful: too much water pouring/spraying into the intake at once will cause waterlogging of the engine, which will bend the rods (connecting rods) and/or ruin your big end bearings, or a combination of both.

That's why I raise the question as to what makes you think you have a serious combustion chamber carboning issue to begin with?

Q.
 
This technique isn't about water injection and octane, it's about thermally shocking the deposits.

I've done it with a quart of ATF, and an product (Redex) that was sold for the purpose.

And it's not about hydrolocking an engine...a 2 litre with 10:1 compression ratio needs about 50ml of water in the cylinder on a single stroke to be able to hydraulic it...a litre over a minute is about 1% of the e water that would be required to hydraulic the engine.

And thousands of times what would be running through the engine if water injected.
 
I had severe carbon buildup that multiple bottles of Techron and Gumout All In One Complete largely fixed. By largely I mean low single digit improvement in mpg and car no longer being unable to accelerate beyond 80mph and also not shaking on the way up to 80mph.

I then did maintenance dosing but there was still a noise at low rpms while accelerating and a lack of smoothness at the same rpms.

Rather than try water or another at home method, I paid Walmart $20 for their fuel injection service and lo and behold, this final issue went away. Engine performance improved even more and seems to be getting better all the time especially after a several hour interstate journey at 100f+ where I pushed to 90mph+ whenever possible.

I've also reset the engine management system to allow it to relearn.
 
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