Portable Generator use in cold weather

Dave_eng

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A relevant cold weather topic has to do with portable generators.

For those companies who will post operating temp spec's, the low limit is not very low. The crankcase vent line freezes and the oil is forced out of the crankcase.

This happened to me with a Honda EM3500 in 1998 during a major ice storm. Only in the last year have I seen the issue addressed by manufacturers.

Honda provides this advice:

Cold Weather Kits
These special cold-weather kits were created to address some unusual operational issues with Honda generators operated in extremely cold environments for extended periods of time. While all Honda generators can operate quite well in cold weather, there are some very rare cold-weather conditions where it is possible for water to collect and freeze inside the crankcase breather tube fitted between the air cleaner and crankcase. When this happens, the formed ice can block air flow and possibly cause the generator not to work properly, or some oil to leak out of the engine.
To prevent this, Honda has developed a small, 10-watt heating coil that fits inside the tube and keeps the area warm enough to prevent ice from forming. The heating coil gets its power from the generator by connecting to the back terminal of a selected receptacle. Each kit is unique to a specific generator, and some come with special insulated parts to help regulate the temperature. Once installed, the cold weather kit may remain on the generator; it is okay for it to operate year-round.

Generac sells s silicone heater which runs off the generator 110 volt circuit.
It is wrapped around the crankcase vent line.


Dave
 

100 td

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Interesting to know Dave, just out of curiosity, are you talking about the breather from the valve cover to the carby that froze up?
I've used a few generators in extreme cold conditions and fortunately haven't had that problem, but that could be due to the fact I mostly used a Honda EU2000I which are encased and probably warmed the carb slightly to stop it happening, as well as being dry and cold. I do recall using an Em2200, as well as something bigger but don't recall the model, a 5kva approx. However I would have thought there would be enough heat from the crankcase vapor to keep the vent open, but there is a large volume of cold air being drawn in continuously to the engine to freeze the end of the tube up!
Bigger problem was starting a Honda quad bike at minus 35 with no heaters or boosters!
 

Dave_eng

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Interesting to know Dave, just out of curiosity, are you talking about the breather from the valve cover to the carb that froze up?
I've used a few generators in extreme cold conditions and fortunately haven't had that problem, but that could be due to the fact I mostly used a Honda EU2000I which are encased and probably warmed the carb slightly to stop it happening, as well as being dry and cold. I do recall using an Em2200, as well as something bigger but don't recall the model, a 5kva approx. However I would have thought there would be enough heat from the crankcase vapor to keep the vent open, but there is a large volume of cold air being drawn in continuously to the engine to freeze the end of the tube up!
Bigger problem was starting a Honda quad bike at minus 35 with no heaters or boosters!
Yes that is the tube. Usually rubber, about 4 to 6" long and sometimes with some bends in it. Don't forget you have two fans moving air about around the generator. One on the engine and one for the alternator.

Snow blower engines are specially designed to work in cold weather and blowing snow. I am talking 8 to 12 HP ones. First they come with no air filter, and the enclosure around the muffler is designed to keep the carb warm. The same engine would not survive warm weather operation.

I am old enough to know all about carb icing. The expanding air passing through the venturi(s) in the carb would flash freeze any moisture and soon ice closed off the carb bores.

Heat riser valves directed exhaust manifold heat up into the intake manifold casting and there by conduction warmed the carb. Air filter housings had thermostat vacuum controlled valves to suck warm air from around the exhaust manifold so the engine was getting warm air.

The downside was that you could get the carb too warm and start experiencing vapor lock.

In these days of emissions, no manufacturer would tell you to take the tube between the cylinder head valve cover and the carb intake off but that is what I did with my EM3500 for the balance of the storm.

When it froze up, all the crankcase oil was on my front porch. Lucky the engine had a working low oil cut off.

Dave
 

100 td

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And just to get off topic, when did they first start using them, and when did other manufacturers start using them (small gasoline engines)?
 

Oil pan 4

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It usually doesn't get that cold here, but when it does and if I need to run my generator I will pull the crank case vent tube off the engine.
 

rjcorazza

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Definetly good to add to the ole knowledge base. Are there any consequences to removing the breather tube? It rarely gets into single digits (f) in my area so I suspect that the breather would not freeze up on my 7k Generac.
The comments about snowblowers are a little late for me... I got an Ariens blower for sidewalks last year, and spent considerable time recently figuring out that it doesn't have an air cleaner to service.
 

Dave_eng

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Definetly good to add to the ole knowledge base. Are there any consequences to removing the breather tube? It rarely gets into single digits (f) in my area so I suspect that the breather would not freeze up on my 7k Generac.
The comments about snowblowers are a little late for me... I got an Ariens blower for sidewalks last year, and spent considerable time recently figuring out that it doesn't have an air cleaner to service.
Removing the tube.

You have unfiltered air entering intake. Plug the hole when tube removed.

Oily fog gets unto engine. Clean and reinstall tube when not cold.
A visit from environmental police :)
Dave
 

MadMax31

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I recently grabbed a Honda EB2800i because Honda generators never go on sale. Both my pellet stove and my boiler have a few circuit boards so the inverter appealed to me.

I was going to build a cover of sorts, as we have a lot of wind here. Im going to look into that heater as well.
 

Dave_eng

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I recently grabbed a Honda EB2800i because Honda generators never go on sale. Both my pellet stove and my boiler have a few circuit boards so the inverter appealed to me.

I was going to build a cover of sorts, as we have a lot of wind here. Im going to look into that heater as well.
Here is a link to a similar model of generator's heater and where to buy it.
It is an EU2000i. I don't know the difference between an EU and an EB

https://www.babbittshondageneratorhouse.com/product/2897/honda-eu2000i-generator-breather-heater-kit

Dave