Freezing Weather and Radiators?

[Nathan Fowler]

Now that we are getting into the cold season, what do I need to do to keep my cooling system from freezing? Do I add a little anti-freeze in with the water? What is this going to do to my cooling capabilities (or lack thereof with the banana radiator)...

[Stan Stanford]

Nathan,

I added Anti Freeze to mine last winter (which is what I have done wih all of my dirt bikes in the past) and it seemed to work fine. I did test the mixture to see what temps it would protect under. I have also heard of some people, who do a complete tear down in the off season just drain the radiator completely (make sure all lines and hoses are DRY!!!) and you can purchase an engine crate online and they actually store their engine in doors. A little overkill for me. Like I said the Anti Freeze worked good for me last year. I am sure some of the other guys on here have some tricks that they do, so hopefully you will have a few choices to decide on.

[Michael Fiyak]

I'm going to do a tear down. Driving it on a cold surface isn't all that fun anyway. I will just through away all the lines and redo them all in February.

[Jason Frank]

You might want to use water wetter because its made for smaller engines and is also eco-safe. Antifreeze will work but its illegal to run at BTK and Big South due to concerns of crashes and spilled antifreeze.

You can drain the system over the winter, but you can also replenish the engine with fresh distilled every month and run the kart maybe twice a month on the stand to keep the engine fresh. Two-strokes do not like sitting inactive for long periods of time.

I would just run the engine every two weeks. You might spend maybe 10 bucks over a few months in gas, but its safe for longevity.

[Nathan Fowler]

What about events during the colder months? (For example, I have an Autocross on December 4th) Do I just drain the cooling system and fill it up before each event?

[James Frank]

if you are storing the kart outdoors i would recommend an anti-freezing solution. if you can wrap it up that might help. as far as racing goes, you will want to tape up the radiator. every row of "duct tape" adds about 10-15 degrees of higher temps while racing. when you are just starting the kart up in the morning. prime it well, lift the choke, and put a towel over the radiator to warm it up sooner. avoid hard throttle applications until the radiator/engine is warm to to the touch. once on track and the water temp is around 100, you can drive harder. give it time and dont try to rush it. if the ambient temp is around 50 or above, it usually only takes less than 10 minutes to warm up the kart before you go on track. the engine may idle higher when its cold, but it shouldnt be much higher. mine runs around 2200 in cool weather, and then slows to around 1800 once warm.

[Jason Frank]

Depending on how often the kart is being run. If your running November 5th and again at an autocross on Dec 4th, then I would just drain your system after the kart race, flush it clean, replenish it with new distilled water and some water wetter (about 3 oz for 1/2 gallon of water). You can mix it up before you put it in or just add it to the radiator and it will circulate. You also might slant the radiator back some more to decrease the cooling effect in colder weather. Obviously, you can only go so far. I would add tape for the runs in autocross as warm up time is limited as well as runs are extremely short.

For storage, you can use antifreeze, but its just you have to remove it before the next racing season. I know it sounds anal, but its one of those things that youd rather not get caught using because of disqualifications.

Overall, for the short autocross runs in cooler weather:

use tape to keep the radiator at a specified temp after warm up.
use the choke during warm up
If its sunny out, keep the kart (or at least the radiator) in the sun
slant the radiator to decrease cooling effect
richen mixture as cool/dry weather increases cold seizure possibilityI know theres a water temp regulator that goes on your cooling system and keeps the engine at exactly 130 degrees. I cant remember the name or the cost. I have seen it used and it works perfectly without adding tape or changing radiator angles.

Oh, I dont think autocross (SCCA or TAC) cares about antifreeze. For overall engine safety, Id use antifreeze during the autocross, just not for kart events. Otherwise, Water Wetter and distilled water with tape on the radiator and rich carb jets for safety. Hope this helps.

Better to run safe than stick the piston