How do i flush the cooling system?

Joined
Apr 15, 2008
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Eatonville, WA
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2006 ST
I am getting ready to change my stuck thermostat. Is there anything speacial to flushing the system or do i just pour distilled water in the radiator and then drain that.
 
Joined
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Deer Park, WA
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2006 ST1300
I drain radiator and the engine bolck, add distilles water, then get it up to temp so radiator fan kicks in and drain both. Actually I went the distilled water twice because I got some little particles out of the block.
The bolts that drain the block are a little difficult to get to but not as bad as some have said.
Have Fun.
 
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Deer Park, WA
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:yes:
Much better explaintion of the process.
I also cleaned out the radiator outlets. You will find the black paint inside the openings when you take the hose off. I also found black paint chips in my antifreeze when I filtered it through a coffee filter. I also flushed out the radiator several times while I had it out. One other thing is, if you go this far, you can take the radiator and soak it in hot soapy water in your bath tub to loosen the dirt around the cooling fins.

I wish I had been organized and had the breeze clamps when I did this.
 
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Everything that has been said is good practice. What hasn't been said is that regardless of where you think you should place your drain pan to catch the coolant, it won't be 'far enough'. I had the coolant flowing into the pan until I rmoved the radiator cap, then it showered my garage wall! Forewarned is forearmed.
 
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Those breeze clamps aren't necessary if a quality industrial worm clamp is properly installed. As a professional technician, I've been working on cars for many years and never had a quality worm clamp leak...and I live where temps range from 95 to -30f. Techs up here actually prefer a good worm clamp over the spring clamps used by most cage mfgs, as those allow the hose to expand as the aluminum water necks get some corrosion, and cause leaks. Good worm clamps will hold tension and keep the hose from leaking. Use a quality wide worm clamp and install it correctly, and you won't have any leaks.

Oh- and the breeze clamps aren't perfect either. The tech next to me at work just pulled several off a Volvo today because the hoses were leaking. For some reason the springs were broken, allowing the clamps to lose tension. I'm guessing age and heat extremes caused the failures, but its just a guess. Good worm clamps went back on instead.
 

Tom Mac 04a

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The bolts that drain the block are a little difficult to get to but not as bad as some have said.
Never took them out ... if you do a flush with distilled water and then refill with anitfreeze, I just added a bit less water to the mix to makle up for what was in the engine ( prob just a pint ).

I had the coolant flowing into the pan until I rmoved the radiator cap, then it showered my garage wall
I followed anothers advice from prev threads and leave on the cap, slightly/slowly pull bottom hose and the antifreeze dribbled out, didn't splill more than a few drops.
 
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It is a good idea to have the radiator cap removed before you pull the hoses. I do not see how you can do it without a little mess.
Make sure you clean up the Kitty coolaid or your neighbors cat might get into it. :sm1:
 

dduelin

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This is getting way more complicated that it needs to be. Not every bike has leaks and not every bike needs to have the clamps and hoses replaced at 15,000 or 20,000 miles. That is nothing more than a waste of someone's time and money. If doing just a coolant change or thermostat replacement follow general flushing practices or the service manual or I can send you an excellent step-by-step tutorial that appeared here 6 or 7 years ago. It is designed to step you through the ST1300 coolant and/or thermostat replacement. It is easy.

When and if you have a leak, or at the first major service at 16 or 20,000 miles, go in behind the radiator and under the throttle bodies and tighten the OEM clamps with a long screwdriver. Just snug them up, don't go crazy. Too tight and the hose does not have the resilency to seal through the many repeated hot/cold cycles it endures. You might have to do this again in 50,000 miles or so. I did not have to do this again until 60,000 miles after the first service at 22,500 miles.

Both Breeze and Ideal make perforated and non-perforated worm gear band clamps. Both are adequate for the job and the OEM ones are just fine. My original clamps have worked as designed for over 100,000 miles.
 
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... If doing just a coolant change or thermostat replacement follow general flushing practices or the service manual or I can send you an excellent step-by-step tutorial that appeared here 6 or 7 years ago. It is designed to step you through the ST1300 coolant and/or thermostat replacement. It is easy...
I'd like to see the article, as my bike is coming up on coolant change/flush time.
 
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I plan to do a coolant change soon, possibly this weekend, since mine is waay overdue. I did a coolant change w/radiator removal, flush, etc. a few years ago when I had to replace the sticking thermostat, so don't have any plans to remove the radiator this time around unless I encounter something that might make it worthwhile to do so. I need someone to refresh my memory regarding the flush procedure. IIRC, I think I followed someone's suggestion to use a 50/50 mix of distilled water & white vinegar to fill the cooling system, run it up to operating temp until the fans kicked on, let things cool down, then drain & repeat with 100% distilled H2O before putting in the recommended coolant. Does this flushing procedure sound familiar to anyone? I think I would prefer this method over using an automotive cooling system flush product from O'Really or AutoZone, especially if it would be gentler on the ST and equally effective. Any suggestions?

Thanks, Don
 

SupraSabre

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To avoid a BIG mess and only have a little mess... Pump out the coolant in the radiator using a hand primer pump (boat motor primer pump) like you can pick up at Walmart for a few bucks. Also a big tub (I got one from Lowe's in their concrete area.) to catch the coolant as it spills all over! :eek:4:
 
Joined
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Baton Rouge, LA
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'98 Valkyrie
Hi guys,

I'm doing a coolant change and I have some questions. Reading some of the posts and replies have helped, but I still need a little assistance. First, how many cylinder drain plugs are there and where are they located? I did find one and I assume it was correct because coolant came out. This one was on the right side. Someone mentioned "both" plugs, so I'm looking for the "other" one. Second; I've recovered approximately 2 qts. The manual says engine and radiator contain 2.81 qts. Am I leaving some in the block? By the way, the radiator was full when I started.

As a side note, I drained the fluid without any mess. I did this by inserting some plastic tubing into the radiator and siphoning coolant out. Then, I snaked the same tubing into the lower radiator hose as far as I could (I'm pretty sure I made it all the way to the block) and siphoned more coolant. When I disconnected the lower rad hose, not much came out. I "curtained" off the engine and surrounding area with some plastic sheeting that I had hanging into a bucket and voila! No mess. I did the same "curtaining" effect for the cylinder drain bolt to protect the manifold and nearby area with same success.

Thanks for any and all help.

Bryan
 
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Jan 8, 2011
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Arizona
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It is a good idea to have the radiator cap removed before you pull the hoses. I do not see how you can do it without a little mess.
Make sure you clean up the Kitty coolaid or your neighbors cat might get into it. :sm1:
I find leaving the cap on easier. Instead of a "drain pan" I use a rubbermaid storage box (the smallest size).
Then I use a deep, wide funnel that I got for free from the recycling company. I place the tub underneath the hose,
put a couple drops of PB blaster on the end of the hose, wait about 30 seconds, then hold the funnel up to the bottom of the hose fitting.
It slides off and both the hose and the fitting fit inside the funnel, directing the flow into the tub.
I've never had a single drop touch the garage floor doing it this way.
I remove the cap after most of the fluid is drained.
.02
 
Joined
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Arizona
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I plan to do a coolant change soon, possibly this weekend, since mine is waay overdue. I did a coolant change w/radiator removal, flush, etc. a few years ago when I had to replace the sticking thermostat, so don't have any plans to remove the radiator this time around unless I encounter something that might make it worthwhile to do so. I need someone to refresh my memory regarding the flush procedure. IIRC, I think I followed someone's suggestion to use a 50/50 mix of distilled water & white vinegar to fill the cooling system, run it up to operating temp until the fans kicked on, let things cool down, then drain & repeat with 100% distilled H2O before putting in the recommended coolant. Does this flushing procedure sound familiar to anyone? I think I would prefer this method over using an automotive cooling system flush product from O'Really or AutoZone, especially if it would be gentler on the ST and equally effective. Any suggestions?

Thanks, Don
After removing over a dozen frozen, stuck and corroded thermostats from members bikes, I would strongly suggest replacing the thermostat everytime you flush the coolant, or once a year, which ever comes first.
I've found them failing in as little as 2K miles!
I change mine yearly as a precaution.
I have alot of folks tell me their T-stat is still in good working order...it only takes 15 minutes to reach three bars!
Then I remove and show it to them :D
 
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dduelin

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After removing dozens of frozen, stuck and corroded thermostats from members bikes, I would strongly suggest replacing the thermostat everytime you flush the coolant, or once a year, which ever comes first.
I've found them failing in as little as 2K miles!
I change mine yearly as a precaution.
I have alot of folks tell me their T-stat is still in good working order...it only takes 15 minutes to reach three bars!
Then I remove and show it to them :D
What did you do? Delete all your posts about the importance of replacing hoses and clamps at the first or second service or other low mileage?

Dozens to me means 50 or 60 member's bikes. Can you really say that you have replaced 50 or 60 thermostats, some of then multiple times? Who paid for that waste of time and money? If the coolant is serviced on time there will not be a corroded thermostat in the housing. If was not maybe you did someone a service, otherwise replacing the thermostat out of hand every year is a waste. On neglected bikes maybe not.

To the question, there is a second drain bolt that is found under the left front cylinder's exhaust pipe. It is a bolt just like the one on the right side. A cup or so runs out. If the coolant has been serviced on time of 2 years or 24,000 miles just draining and replacing the coolant in the block and radiator should be sufficient. I pull the radiator off each time and flush it with clean water. That allows a look at the thermostat housing and the clamps and hoses in the vee of the engine behind the radiator as well as cleaning the fins of the radiator very well.
 
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the Ferret

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My dealer quoted me $ 225 to do a coolant flush. Does this seem reasonable for the time/difficulty of the job?
 
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