BCS 853 & BCS Snowblower with Honda GX390 Throttle Engine Speed Issues

[josiahgarber]

I bought a BCS 853 2 wheeled tractor this fall and am having some problems with it when snowblowing.

The GX390 engine starts up with no problem and responds properly to the throttle for a while. It also has plenty of power when snow blowing.

However, after snowblowing for about a half hour the engine no longer responds to the throttle when I lower it. It keeps running at a high rpm, but lacks power when snowblowing or under load.

Do you think this is related to ice binding something up or does it sounds like something else?

I appreciate anyones help.

 

[devkrev]

Have you tried just running it for a while in the garage or wherever? With/without PTO engaged?

Does it only happen when you snowblow?

Is your air filter clean?

 

[josiahgarber]

I ran it for a little while in the garage and it was fine. I didn't want to run it too long because of carbon monoxide though.

It seems to only happen when I snowblow, though I haven't been doing any other activities with it that run the engine wide open.

I assume the air filter is clean, as the unit is next to new. I will check it when I go out again.

Thanks for your help.

 

[josiahgarber]

Have you tried just running it for a while in the garage or wherever? With/without PTO engaged?

Does it only happen when you snowblow?

Is your air filter clean?

I think you may be on to something with the air filter. Perhaps the air intake is getting partially blocked with snow (it was still snowing when I was snow blowing).

I did a section behind the barn out of the wind and snow and it was fine the whole time. Then I started a section where a lot of snow built up on the engine and I had the problem.

If there is a lack of air can that cause it to run at a high speed even when the throttle is at idle? To rich of a fuel mixture perhaps?

Thanks for your help.

 

[Jens767]

Hi josiahgarber


I have a BCS 740 with the same Honda engine as you.

As you know, the throttle lever on the handlebar is connected to the throttle via a cable. I suspect that after working a while in snowy conditions, you might have accumulated so much snow on your engine, that the throttle stays open, even though you reduce the setting on the handlebar. If you take a look between the air filter and the muffler while you operate the throttle lever, you should be able to see the throttle move accordingly. Note that the throttle lever opens the throttle via the cable, whereas a spring between the muffler and the fuel tank closes the throttle - or at least it tries to. Perhaps this explains the high rpm's?

The lack of power that you experiences, is due to either too little air or fuel - or perhaps even both.

Air is sucked into the air filter from underneath, so this area has to be free of snow. If the engine cannot breathe freely, the mixture will become too rich, and you will see the engine smoke and loose power. By the way, something similar happens when you move the choke lever to the closed position, to start a cold engine. This enriches the fuel-air mixture, making it easier to start the engine. As soon as the engine starts, you can gradually move the choke lever towards the open position, to allow the engine to breathe freely.

Working in cold conditions, can also lead to fuel starvation, do to ice building in the fuel system, either as carburetor ice or as ice forming in the fuel lines - perhaps even both.

When fuel is sprayed into the carburetor, it vaporizes and the air temperature drops as much as 70 degrees F. This means that carburetor ice can form when the air temperature is as high as 90 degrees F (32 degrees C), and if the humidity is high [Crane, 1996].

Ice in the fuel lines occurs, when small water droplets freezes. Even with the outmost care, it is hard to avoid water totally. Often it comes from humid air condensing in the fuel tank, leaving small amounts of water at the bottom. This water might end up in a narrow space in the fuel system, and when freezing, will block the free fuel flow. As this case is the opposite of the air filter problem, the fuel-air mixture will become too lean, but also lead to a loss of engine power.

To minimize the risk of water in the fuel system, it is vice to keep the fuel tank full at any time, and thereby minimizing the air volume in the tank. Keeping the tractor in a dry place at constant temperature further minimizes this risk. These days small amounts of alcohol is added to gasoline in many countries, which helps reducing the risk of ice, as alcohol solubilizes water. The small amount of alcohol is then burnt in the engine - problem solved. In very cold regions like northern Scandinavia, it is not uncommon to add a little isopropyl alcohol (IPA) during winter. In the US, I think such products are often sold as "gas dryers"?


Best regards

Jens

 

[T_e_r_r_y]

I, myself have never seen an air filter on a snow blower. The assembly yes, but not the actual paper or foam elements.
The reason I have been told is, that the melting of the snow onto the filter, then freezing. Thus
changing the fuel/air mixture making the engine run rough, until the filter completely ices over.
Should check your owner/operators manual and see if, in the winter time, you need to remove the air filter and then add a heat shield to cover the carb
The heat shield covers the carb and the throttle linkage.
Using the heat from the muffler, thus melting what little snow that is sucked into the carb and NOT onto or into the filter.
Some people just change engines and not realize that the little things like, a heat shield, belt covers,
the belt fingers, and the removal of the air filter are really necessary!
T.J.

 

[leonz]

I bought a BCS 853 2 wheeled tractor this fall and am having some problems with it when snowblowing.

The GX390 engine starts up with no problem and responds properly to the throttle for a while. It also has plenty of power when snow blowing.

However, after snowblowing for about a half hour the engine no longer responds to the throttle when I lower it. It keeps running at a high rpm, but lacks power when snowblowing or under load.

Do you think this is related to ice binding something up or does it sounds like something else?

I appreciate anyones help.

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Adding to the excellent comments provided by the TBN members;

The way the cables and linkages are set up on the GX models are an
issue in winter if snow and ice get in there. I always kept my GX340 on
my firewood processor covered for this reason adn the tarp held the heat
in when I heated up with the salamander as it also had a 25 gallon oil tank.

I will say that since your engine is miss behaving when hot the possibility of
ice and melt water and more ice affecting your throttle linkages adds to your
problems as the the GX390 cannot respond to the load as the linkages/cable are
binding because of ice build up and if the garage is not adequately heated you will
still have ice and snow on it.

If the frozen cable is the issue the cable sheath will shift while trying to push the throttle
linkage to increase the engines RPM-you may just not see this happening.

if you can buy a can of cable lubricant or fluid film to spray inside the cable sheath and work the throttle
linkage to get it to move more freely that will help you. WD40 will work in a pinch but fluid film spray
with the nozzle tube extension is the best way to handle this.

Also you need to dry off the snow blower by letting it idle to heat up the engine and throttle linkages
before you pull it in the garage. do not forget that the BCS is going to continue to attract cold air and
moisture to the the engine and everything connected to it.

Me I have gotten way too lazy and use my salamander to warm up the mule and then melt all the snow and ice
off of it and the snow caster when I am done with it before I finally park it and cover it with a tarp if its snowing.

I use a tarp to hold the heat from the salamander long before I even turn the key when I need to clear the
driveways too and it saves on engine wear and heats the transmission oil up long before I start it up.

We still have plenty of winter before us and investing in a small salamander is an investment that pays
huge dividends. I bought my first space heater in 1994 and I wish I had bought one in 1978 when I bought
my home on the mountain as I live at 1140 feet above sea level and it gets very cold and the two car garage that passes for tow car garage was an afterthought by the previous owner of this home as it barely has room to park in it with the sloped roof and.......................................................................................

Make sure its dried off before you put it away next time and lube the cables and linkages change the air filter and clean and oil the foam safety element before you use it again.

Heating your engine for 20-30 minutes at idle before and after up saves you time and engine wear-I had my last truck last me for 15 years before I had to park it as I used a block heater the year round and a salamander to heat it up from the end of September to late April if it was really cold out.

you will use a bit more gas but the BCS will run so much the better for it.

 

[josiahgarber]

We still have plenty of winter before us and investing in a small salamander is an investment that pays
huge dividends.

What is a salamander? Sorry for my ignorance.

 

[leonz]

What is a salamander? Sorry for my ignorance.

Hello Josiah Garber,

No need to apologize, a salamander is also referred to as a torpedo heater.

They are a forced draft space heater capable of heating
large buildings and open work areas as well as melting ice and snow,
heating engines and many other jobs like heating a large covered
concrete pour in winter to let it cure properly.

Some units are propane fired and others are multifuel fired space heaters.
The unit I have can burn K-1 and K-2 Kerosene, diesel fuel and all the grades of jet fuel

The propane units are smaller and weigh less but are difficult to use in cold weather
unless you remember to keep the burner unit minus the propane bottle inside where it
is always warm as compared to the kerosene fired unit in the garage as the fuel tank
is under the burner housing.

The propane fired units also burn through propane quickly and would require a large bottle
for extended use and are not as economical to run as a kerosene fired unit.

The smallest kerosene fired unit sold would be more than adequate for warming up the BCS and melting the snow after clearing the areas you need to have cleaned out. The other added benefit is that your crankcase oil can stay at 30 weight and not require a 10W-30W multiple viscosity oil.

 

[BillyDBrown]

While the warm dry start obtained using the salamander is attractive, targeting a kerosene fired heater on a gas engine and tank gives me some pause. Do you agree concern is warranted? Do you take any safety precautions?

I have electric but lack heat. What do you think about using a heat lamp beneath a tarp instead?