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How to Flush the Radiator on an ATC 250R


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How to Flush the Radiator on an ATC 250R
« on: October 17, 2016, 07:50:18 AM »
How to Flush the Radiator on an ATC 250R

Is there a proper procedure for how to flush the radiator on an ATC 250R? Other than just draining the coolant, is there a recommended method that will improve cooling?

Many Thanks!


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Re: How to Flush the Radiator on an ATC 250R
« Reply #1 on: October 19, 2016, 09:59:46 AM »
How to Flush the Radiator on an ATC 250R

Here's my method for flushing my 250R radiator. This isn't something you need to do all the time, but I would recommend a radiator flush at least once after you buy your machine for peace of mind. These three wheelers are 30 years old and you'll have no way of knowing what past owners put inside the radiator over the years. And then again, if you have overheating problems and it may be in your best interest to flush it out to ensure you have clean coolant and no surprises when you drain it.

Start with a drain pan, place it under the 250R.  Take the radiator cap off and then take out all the drain bolt. Some guys will remove the hose clamp and coolant hose near the bottom of the radiator. Whatever causes less of a mess will work just fine.

After the old coolant has finished draining, close up the drain or lower hose. Don't move your drain pan yet,  you can fill the radiator with water and repeat the process until you get clear water flowing from the drain. You may or may not have to do this more than once.

Do you need to flush the 250R radiator with distilled water for this step? I don't believe so, since this water will be drained before the process is complete. If you feel the need to rinse out the radiator with distilled water, you certainly won't hurt anything so go for it if it makes you feel better.

Do you need to use coolant flush? In my opinion, this decision is based on how`dirty the initial coolant drain was.... If your came out looking fairly clean, I wouldn't use the radiator flushing products at all. Again, the condition of the original coolant will also dictate whether or not you want to do a complete cooling system flush.

This would require closing the drain and returning the hose (if you removed it) and following the manufacturers instructions on using their product. This can vary a little but it usually involves warming up the motor and circulating the flushing product and then flushing with clean water again.

Now to refill your radiator.... I use a mixture of 50% coolant and 50% distilled water. I use ethylene glycol-based coolant that has no silicates, the brand of your choice. Silicates are believed to wear down the impeller blades in water pumps.

As for the distilled water, you can buy it at any supermarket and most convenience stores. Using tap water is never recommended because of the minerals, iron, contaminants, etc. which are known to rust and corrode internal cooling system parts.