Rad Flush

redridernl

redridernl

Well-known member
I didn't want to derail the Red Dawn thread so... ;)

It's not a hard thing to do but it was time consuming for me. Aside from getting access to things on my bike, I had to flush it (fill and drain) about 8 times before I got rid of all the coolant. It took several hours so I don't see how it could be done at the track unless people aren't really flushing it and instead just letting it drain. Am I missing something?
 
8 times?

Dump coolant, dump a bottle of water through and replace with ww
 
redridernl said:
I didn't want to derail the Red Dawn thread so... ;)

It's not a hard thing to do but it was time consuming for me. Aside from getting access to things on my bike, I had to flush it (fill and drain) about 8 times before I got rid of all the coolant. It took several hours so I don't see how it could be done at the track unless people aren't really flushing it and instead just letting it drain. Am I missing something?
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You're doing it wrong
 
drain rad, drain overflow and use a hose to circulate water through.....some coolant will be in t he block, so drain flush one or two times will get rid of almost off it
 
I did it this way at first too, which I realize now was wrong....



redridernl said:
I didn't want to derail the Red Dawn thread so... ;)

It's not a hard thing to do but it was time consuming for me. Aside from getting access to things on my bike, I had to flush it (fill and drain) about 8 times before I got rid of all the coolant. It took several hours so I don't see how it could be done at the track unless people aren't really flushing it and instead just letting it drain. Am I missing something?
Click to expand...
 
Wrong or thorough? It took that long for it to stop coming out green. What's the point of doing it if you don't get all of the coolant out? Up until probably the sixth time it was still coming out dark green.
 
Not wrong... just not efficient.

I can usually get it clear by the second or third flush of water........ (15-20mns)

After you fill it with water, make sure you slosh it around GENTLY side to side as it's draining. there's always some "green" left sitting somewhere.

it's nice to have a helper pour water in the rad every 10-20 seconds to get a constant stream coming out.

If it's coming out dark green, you were in need of a coolant flush anyway. that could also contribute to why it's taking so long (in addition to your technique).
 
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It takes multiple flushes to get nearly all of the coolant out becuase there are low spots in the engine cases, hoses and rad that won't drain when you simply remove the plug.

This is how i've always done it.

- drain overflow reservoir
- open rad cap
- remove drain plug and drain coolant
- re-install drain plug finger tight then fill rad with deionized water
- start bike then remove drain plug again
- while the cooling system is draining, keep adding deionized water to the rad to keep it roughly full
- when fluid draining becomes clear stop adding water and shut off bike and allow remainder of fluid to drain
- re-install drain plug and torque properly
- fill cooling system with deionized water and Water Wetter
- re-install rad cap
- add fluid to reservoir if you desire

Doing it with the motor running (and water pump pumping) helps mix and dilute whatever coolant is still in the cooling system a lot faster than simply filling and draining over and over again. I get two of the 4L jugs of deionized water and it's never taken me more than 8L to completely flush the cooling system.
 
I would drain it, seal it up, fill it, run the bike and drain. Then repeat the whole thing. Thanks for the info. Caboose, I'll probably do it your way next season.
 
I usually just use the garden hose when I am trying to flush all the coolant out, once it comes out clear I then make sure it is empty and add my mixture of distilled/water wetter and am good to go. Usually only takes about 20-30 mins as others have stated.
 
Ould said:
I usually just use the garden hose when I am trying to flush all the coolant out, once it comes out clear I then make sure it is empty and add my mixture of distilled/water wetter and am good to go. Usually only takes about 20-30 mins as others have stated.
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Hose water or tap water should usually be fine for flushing it but I was using well water for a few seasons and our water was very hard. I did not want the calcium and other minerals being introduced into my cooling system.
 
I've been doing it wrong all this time. I figured it out when I went to put antifreeze back in the bike and what came out was already bright green!

So we have to flush everything out, fine. But then how do we make sure to get the right mix back in if the system is never quite empty? I mean 50/50 antifreeze or 5% Water Wetter or whatever it is, will also need to be flushed through the system for a while in order to get those proportions right in the end. No?
 
caboose483 said:
It takes multiple flushes to get nearly all of the coolant out becuase there are low spots in the engine cases, hoses and rad that won't drain when you simply remove the plug. This is how i've always done it. - drain overflow reservoir- open rad cap- remove drain plug and drain coolant- re-install drain plug finger tight then fill rad with deionized water- start bike then remove drain plug again- while the cooling system is draining, keep adding deionized water to the rad to keep it roughly full- when fluid draining becomes clear stop adding water and shut off bike and allow remainder of fluid to drain- re-install drain plug and torque properly- fill cooling system with deionized water and Water Wetter- re-install rad cap- add fluid to reservoir if you desireDoing it with the motor running (and water pump pumping) helps mix and dilute whatever coolant is still in the cooling system a lot faster than simply filling and draining over and over again. I get two of the 4L jugs of deionized water and it's never taken me more than 8L to completely flush the cooling system.
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Great method caboose def will do it your way!
 
fastar1 said:
I've been doing it wrong all this time. I figured it out when I went to put antifreeze back in the bike and what came out was already bright green!

So we have to flush everything out, fine. But then how do we make sure to get the right mix back in if the system is never quite empty? I mean 50/50 antifreeze or 5% Water Wetter or whatever it is, will also need to be flushed through the system for a while in order to get those proportions right in the end. No?
Click to expand...

If you know the capacity of your cooling system you can do the math.

If capacity is 4L but it only takes 3L to fill it after you drain then you know there is 1L being held in varios low spots. In that case just flush and drain with clean water then mix 2L coolant with 1L water and fill it up. That should work out to roughly 50/50.
 
What do you do with all of this fluid you've flushed
 
Twoth said:
What do you do with all of this fluid you've flushed
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Dump it into an empty windshield washer or old oil jug, mark it so I know what it is, and bring it to the Waste Management hazardous materials drop off location when I've accumulated enough material to make the trip worth the drive.
 
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