Alcohol to clean combustion chambers??

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Alcohol produce Water and Carbon Dioxide during/after combustion. Since water/steam helps clean carbon from the combustion chamber, will the Water produced by the combustion of alcohol help clean the chambers? If it does, than I would think that our 10% alcohol fuel that is sold at the pumps would help clean the combustion chambers, but it doesn't.
 
OK, if it does clean, than it doesn't do it as good as top tier fuel.

We have had 10% alcohol in our gas for several years. I have seen cylinder heads at my friends shop that were run with [censored] gas and have a lot of carbon deposits. then I see cylinder heads with 2x the miles where the owner used top tier gas, and the chambers are fairly clean.

If you are a chemist, you would know how much water is produced, and if it would help. I am not a chemist, so I don't know
 
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Putting around town will carbon up a head regardless of what gas you use.
Lot's of highway driving will keep them fairly clean regardless of what gas you use.
 
Back when we would run water/alcohol injection on our turbo cars, upon teardown the pistons, heads, turbo, and headers looked like the engine had never been fired. I've always assumed it was the water and not the alcohol. Now that I run straight methanol, everything looks pretty normal.
 
Not being a wise guy I just wanted to know how you knew 10% alcohol did not keep chambers clean. I agree top tier gas will keep heads and valves cleaner than other normal gas will.

I saw a some valves and heads off a 100K test engine at oronite and they were NOT new but so clean I would call them in like new condition.
bruce
 
Water and CO2 are the products of any hydrocarbon combustion. HC + O2 > CO2 + H2O

That is why on a cold day you see condensation in exhaust. It is largely water vapor to begin with and when it cools enough it condenses. Doesn't matter whether the fuel has alcohol in it or not.
 
Part of the reason that (I believe) water and water alcohol injection work is that it can thermally shock the deposits off.
 
Originally Posted By: BuickGN
Back when we would run water/alcohol injection on our turbo cars, upon teardown the pistons, heads, turbo, and headers looked like the engine had never been fired.


I've had the same experience with a Mr. Freeze running the cheapest blue washer fluid we can find.
 
Originally Posted By: BuickGN
Back when we would run water/alcohol injection on our turbo cars, upon teardown the pistons, heads, turbo, and headers looked like the engine had never been fired. I've always assumed it was the water and not the alcohol. Now that I run straight methanol, everything looks pretty normal.

I've heard that many times and don't have any doubts that it is true. Obviously there is a difference between water in the form of vapor as the product of combustion and the effects of injecting it in liquid form, which seems to do the steam-cleaning thing to the engine's internals.

I am curious: how/where is the water actually injected, and how much is used? I once tried to get a similar effect by running a line from the washer reservoir into the intake with a small orifice and used up a gallon in perhaps twenty miles of driving, but didn't see any noticeable change in the appearance of the piston tops.
 
Originally Posted By: glennc
I am curious: how/where is the water actually injected, and how much is used? I once tried to get a similar effect by running a line from the washer reservoir into the intake with a small orifice and used up a gallon in perhaps twenty miles of driving, but didn't see any noticeable change in the appearance of the piston tops.


I'm not sure about other Meth injection kits, but our Mr. Freeze uses less than a gallon a month even with some hard driving. Unlike other kits it only functions with varying vacuum pressures indicating a load on the engine but other kits using an electric pump should have something similar to keep it from running all the time.
 
Mine is progressive starting at 5psi and ramping up from there. Injection point is about a foot from the throttlebody. A gallon will typically last months because I don't hit boost in daily driving. Not sure what the rate is but pump pressure is around 200psi, M10 nozzle, and a gallon will last 4-5 1/4 runs. This was on the 70/30 and 90/10 rubbing alcohol. Haven't torn it completely down with the straight methanol but judging from the turbo and headers that I've taken off, the normal carbon is there. I strongly believe it's the water doing the cleaning.

There is enough injected that if I hit the prime button just crusing around it will kill the motor.
 
Thanks. I'm sure you're right that the water is responsible for the cleaning. If a gallon lasts 4-5 runs then you are using a quart in just a few seconds. Like a garden hose.
 
Originally Posted By: glennc
I once tried to get a similar effect by running a line from the washer reservoir into the intake with a small orifice and used up a gallon in perhaps twenty miles of driving, but didn't see any noticeable change in the appearance of the piston tops.


IF you run too much at a time, you won't get the same effect. I tried using a water bottle with a proportioning valve from a water sprinkler system to run water injection in my car. All I managed to so was make a milkshake in the oil, and cool off my intake manifold. A Devil's Own kit is coming in the mail soon for install on my new boosted car. I don't know of a good way to examine the deposits aside from pulling out the spark plugs.
 
We ran a device called a Vapor Jet when I was younger on our family cars. It consisted of a hose teed into a main manifold vacuum source (that would distribute to all cylinders evenly) and a canister with vacuum adjustment valve. Then there was another hose that pulled air into the canister through a carburetor type filter (one of those old style metal conglomerate type of filters) that sat down in the water or winter mix of water and methanol. With the car at idle, you would adjust the bubbling to a reasonable level. The more the bubbles, the faster the solution would have to be replaced.

My point in telling about this thing was that it kept the combustion chambers of all these engines spotless and the preignition/detonation of the cheap gas was eliminated. My dad had a cylinder head come loose on an air-cooled VW and his mechanic mentioned that he had never seen a cylinder head that clean/spotless.
 
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