Water mist cooling to help prolong life of rings and pistion life when milling ideas.

[Assembler]

Any one use a water mist spray in the intake of the air shroud for extra cooling to help prolong rings and piston life of a air cooled chain saw when making long milling cuts in logs?
Thank you for your inputs.

 

[Assembler]

There is a hand pump up mist water plastic bottle used for spraying one's head and body to help cool off for warmer weather. I thinking this would be a very good start for extra water mist cooling. There could be a small increase in light external corrosion however a high temp paint could help stop it. Maybe two misting water bottles would be better for extra cooling and improving the life of the rings and piston.

 

[ML12]

I just let the saw sit and idle for a couple minutes in between passes, couple that with frequent beer/water breaks and the saws don't ever get dangerously hot.

 

[Assembler]

I just let the saw sit and idle for a couple minutes in between passes, couple that with frequent beer/water breaks and the saws don't ever get dangerously hot.

The idea is to reduce the operating temperature of the cylinder fin cooling area by 100 – 400 degrees to prevent or reduce over heating during a long milling cut. This is even more important when the air temperature is about 85 degrees or more. As a plus continue to run the water mist cooling during the 2 - 3 minute cool down period after a long cut is made.

 

[Assembler]

The idea is to reduce the operating temperature of the cylinder fin cooling area by 100 – 400 degrees to prevent or reduce over heating during a long milling cut. This is even more important when the air temperature is about 85 degrees or more. As a plus continue to run the water mist cooling during the 2 - 3 minute cool down period after a long cut is made.

This would be very easy to do with a car windshield washer pump run at 6 to 4 volts so the output is lower. The thing to watch out for is not getting to much water mist on the spark plug. Maybe a small shield to protect the sparkplug or just the plug boot may work. The idea is to reduce the cylinder temperature around 225 degrees to improve the life of the rings and piston. This steam may also cut down on the fine dust some.

 

[IyaMan]

Spraying water mist into the air intake or making the air filter damp while its running? Wouldn't such moisture affect combustion and/or the air-fuel mix?

 

[BlackCoffin]

I wouldn’t think this would be the best idea mixing water with fuel and oil. Mainly the oil aspect. Water injection proves to work well with diesels, especially turbo diesels in the competition scene running over 100psi of manifold pressure which really helps atomized the water being injected into the intake manifold. To do It right, the water needs to be a fine mist of injection and be introduced into an environment where it has enough velocity and time to atomize correctly before entering the combustion chamber. Tuning a bit richer or a heavier oil to fuel mix ratio will aid in running a bit cooler. Also doing a woods port and aftermarket air filter will gain more power and also let the saw run cooler due to a larger charge of fuel entering the saw per revolution. I would think the safest way to aid in cooling , specifically between cuts, would be a strong source of ventilation going over the saw aiding in removing heat from the cooling fins and cylinder. Generally water introduction with gasoline combustion engines doesn’t work the best. Another source of combustable liquid that aids in cooling, power, and detonation are what are typically desired. For example methanol injection on a turbo gasoline setup to help with detonation when running higher boost pressures.

 

[BlackCoffin]

Spraying water mist into the air intake or making the air filter damp while its running? Wouldn't such moisture affect combustion and/or the air-fuel mix?

Sounds like a great way to wipe out bearings or turn your piston and rings into one unit!

 

[IyaMan]

Hey, if you're worried, how about installing a fan instead? Maybe a small cordless blower that is focused on the fins of the cylender head

 

[Assembler]

Spraying water mist into the air intake or making the air filter damp while its running? Wouldn't such moisture affect combustion and/or the air-fuel mix?

The spray water is on the out side of the engine only mixed with the cooling air. The water is not going through the engine.

 

[Assembler]

Sounds like a great way to wipe out bearings or turn your piston and rings into one unit!

Yes this is a very good point as water will damage parts inside the engine.

 

[Assembler]

Hey, if you're worried, how about installing a fan instead? Maybe a small cordless blower that is focused on the fins of the cylender head

Yes increasing the air flow will help however the cooling efficiency is better with water removing even more BTU's of heat energy for a given air flow.

 

[IyaMan]

The spray water is on the out side of the engine only mixed with the cooling air. The water is not going through the engine.

This may very well depend on you saw and its specific air flow configuration. Many (most... all..??) saws are not sealed between the engine and air intake, with only the air filter covering it. Air filters are not designed to stop moisture, and if it gets saturated, it will start sucking the moisture through into the engine.
Seriously, you're probably asking for trouble to start spraying your engine with water, especially when running.

 

[BlackCoffin]

Unless the water content applied was little enough so it was evaporating off and controlled to just being applied to the cylinder in a manner it would work that way, but I agree with the statement above. It will eventually saturate your filter and creep into the cylinder.

 

[Assembler]

This may very well depend on you saw and its specific air flow configuration. Many (most... all..??) saws are not sealed between the engine and air intake, with only the air filter covering it. Air filters are not designed to stop moisture, and if it gets saturated, it will start sucking the moisture through into the engine.
Seriously, you're probably asking for trouble to start spraying your engine with water, especially when running.

Yes one would have to be careful of what chainsaw to use a water mist on as some saw models have poor air cleaners and seals that would be a problem from the start. One has to make sure that no water is going into the engine in any way.

 

[Assembler]

Unless the water content applied was little enough so it was evaporating off and controlled to just being applied to the cylinder in a manner it would work that way, but I agree with the statement above. It will eventually saturate your filter and creep into the cylinder.

The water drops or mist needs to be controlled so as to not cool the engine to much. You are correct the idea is to apply only enough water mist to have controlled evaporation to increase the cooling or lower the upper cylinder temperature the desired 150 - 225 degrees or so.

The older McCullough chain saw I thinking of cooling has a nice round pipe (that is the air fuel intake) coming out of the crankcase for convenient extending or offsetting of the carburetor out from the crankcase of the engine. Thus making sure the water mist can not enter if a controlled flow or mist is applied to just before the cylinder cooling fins. Since I will be offsetting the carburetor any ways due to the fact of a poor air cleaner (putting on a car size K&N oiled air filter). This will be very straight forward to do. I would like to install a temperature sensor however I don't think there is any room for it except in the exhaust gas area.

If I put a 125 CC size tuned exhaust pipe from a motorcycle then it could be easy to measure the exhaust temperatures while cutting. This can be done as I know of a tuned pipe is used at a very good price.

The important goal is to reduce the upper cylinder temperature a reasonable amount and see what the power output is while cutting.

 

[Assembler]

The water drops or mist needs to be controlled so as to not cool the engine to much. You are correct the idea is to apply only enough water mist to have controlled evaporation to increase the cooling or lower the upper cylinder temperature the desired 150 - 225 degrees or so.

The older McCullough chain saw I thinking of cooling has a nice round pipe (that is the air fuel intake) coming out of the crankcase for convenient extending or offsetting of the carburetor out from the crankcase of the engine. Thus making sure the water mist can not enter if a controlled flow or mist is applied to just before the cylinder cooling fins. Since I will be offsetting the carburetor any ways due to the fact of a poor air cleaner (putting on a car size K&N oiled air filter). This will be very straight forward to do. I would like to install a temperature sensor however I don't think there is any room for it except in the exhaust gas area.

If I put a 125 CC size tuned exhaust pipe from a motorcycle then it could be easy to measure the exhaust temperatures while cutting. This can be done as I know of a tuned pipe is used at a very good price.

The important goal is to reduce the upper cylinder temperature a reasonable amount and see what the power output is while cutting.

I forgot to point out that one also needs to make sure that the water mist can not get into the coil as this could be a problem and could short out the hot coil. Thus the water has to go into the air flow just after where the coil is located.

 

[IyaMan]

The important goal is to reduce the upper cylinder temperature a reasonable amount and see what the power output is while cutting.

Hey man, it sound like you got a plan, so why not go for it.
Honestly, if you can put it together, run it for a while and post pics of what you did with some temp and output results (before & after, and try to make controlled conditions), I think we'd all love to see it.
And if things go south and you have trouble, please don't fret with posting about that too, so we can all learn from eachothers mistakes.

 

[Assembler]

Hey man, it sound like you got a plan, so why not go for it.
Honestly, if you can put it together, run it for a while and post pics of what you did with some temp and output results (before & after, and try to make controlled conditions), I think we'd all love to see it.
And if things go south and you have trouble, please don't fret with posting about that too, so we can all learn from eachothers mistakes.

Yes this is the plan in general. As long as the water is very well controlled spray output just in front of the cooling fins and brings down the cylinder temp at least 150 degrees then the set up will have a positive outcome. The extra weight and plumbing is ok due to the fact it is a big milling saw setup. The goal is to improve on the cooling efficiency over what factory cooling is designed to do be cause of the long hot milling cuts with the cool down periods.

Don't forget that this can only be done if the carburetor, gas tank, air intake, air cleaner and maybe the exhaust is all modified from the factory setup. Again the water has to stay out of the engine parts.

 

[ML12]

Yes this is the plan in general. As long as the water is very well controlled spray output just in front of the cooling fins and brings down the cylinder temp at least 150 degrees then the set up will have a positive outcome. The extra weight and plumbing is ok due to the fact it is a big milling saw setup. The goal is to improve on the cooling efficiency over what factory cooling is designed to do be cause of the long hot milling cuts with the cool down periods.

Don't forget that this can only be done if the carburetor, gas tank, air intake, air cleaner and maybe the exhaust is all modified from the factory setup. Again the water has to stay out of the engine parts.

If you are going to build it, post lots of photos. I agree that a mist aimed at the head only would bring the temperature of the motor down as the water evaporation would pull more energy out of the motor.

If you purpose build a mill and weight isn't an issue, you could just use a water cooled dirt bike engine... think hotsaw, but for milling.