Original Posted By: Hogan, James
Subject: Re: Pietenpol-List: Marvel Mystery Oil - Steam cleaning thecombustionchamberIf memory serves me right, the old P-51 and some other piston driven WWII prop fighters had a water injection system for their fuel. Not sure about the science but worked for them with RRoyce engines etc..Gordon ----- Original Message -----
Re: Pietenpol-List: Marvel Mystery Oil - Steam cleaning thecombustion
Re: Pietenpol-List: Marvel Mystery Oil - Steam cleaning thecombustion
Original Posted By: Gordon Bowen
Subject: Re: Pietenpol-List: Marvel Mystery Oil - Steam cleaning thecombustionMany supercharged and high-compression gasoline burners use water injection. The purpose is to lower the peak pre-ignition temperatures in the combustion chamber, especially at high manifold pressures. Any time you rapidly compress a gas such as air, you get a corresponding temperature increase. If the air is already compressed, and heated, by a supercharger (or turbocharger) when it enters the cylinder on the intake stroke, the compression stroke in the cyclinder can cause the temperature of the already-hot fuel/air mixture to reach the ignition point, causing what we recognize as pinging. Injecting a small amount of water into the intake stream cools it, hopefully enough so that the spark plug gets the honor of igniting the mix.Whether or not such engines are cleaner because of the injection, I can't say.Mike Hardaway ----- Original Message -----
Subject: Re: Pietenpol-List: Marvel Mystery Oil - Steam cleaning thecombustionMany supercharged and high-compression gasoline burners use water injection. The purpose is to lower the peak pre-ignition temperatures in the combustion chamber, especially at high manifold pressures. Any time you rapidly compress a gas such as air, you get a corresponding temperature increase. If the air is already compressed, and heated, by a supercharger (or turbocharger) when it enters the cylinder on the intake stroke, the compression stroke in the cyclinder can cause the temperature of the already-hot fuel/air mixture to reach the ignition point, causing what we recognize as pinging. Injecting a small amount of water into the intake stream cools it, hopefully enough so that the spark plug gets the honor of igniting the mix.Whether or not such engines are cleaner because of the injection, I can't say.Mike Hardaway ----- Original Message -----
Re: Pietenpol-List: Marvel Mystery Oil - Steam cleaning thecombustion
Original Posted By:
Subject: Re: Pietenpol-List: Marvel Mystery Oil - Steam cleaning thecombustionchamberI flew a Convair 440 with P&W R-2800's and they had water injection but it was only used during take off, to allow for higher manifold pressures without detonation. I don't remember if it was pure water or a water / alcohol mix.________________________________________________________________________________
Subject: Re: Pietenpol-List: Marvel Mystery Oil - Steam cleaning thecombustionchamberI flew a Convair 440 with P&W R-2800's and they had water injection but it was only used during take off, to allow for higher manifold pressures without detonation. I don't remember if it was pure water or a water / alcohol mix.________________________________________________________________________________
Re: Pietenpol-List: Marvel Mystery Oil - Steam cleaning thecombustion
Original Posted By: SSchof4277(at)aol.com
Subject: Re: Pietenpol-List: Marvel Mystery Oil - Steam cleaning thecombustionchamberI use to service a fleet of Convairs. All recips. the 2-3-440 series all used "ADI" fluid and was actually nothing more than antifreeze...thats right, Ethylne Glycol. A 50/50 mix (water) tp prevent it from freezing at altitude. It increases compression at High MP's to prevent pre-ignition just as you say.I sure miss the old Convairs. Love those and the Martin 404's were nice too. I got a little stick time but not too much. Most of the flights I "jumped" were PT and I just rode along for the fun of it...and to look for oil leaks streaming out the nacelle's. they usually did despite my beat efforts.Dave...(remanissing) Down in Florida----- Original Message -----
Subject: Re: Pietenpol-List: Marvel Mystery Oil - Steam cleaning thecombustionchamberI use to service a fleet of Convairs. All recips. the 2-3-440 series all used "ADI" fluid and was actually nothing more than antifreeze...thats right, Ethylne Glycol. A 50/50 mix (water) tp prevent it from freezing at altitude. It increases compression at High MP's to prevent pre-ignition just as you say.I sure miss the old Convairs. Love those and the Martin 404's were nice too. I got a little stick time but not too much. Most of the flights I "jumped" were PT and I just rode along for the fun of it...and to look for oil leaks streaming out the nacelle's. they usually did despite my beat efforts.Dave...(remanissing) Down in Florida----- Original Message -----