Coolant Change

Premacy31 · May 18, 2019

Daniel said:
Having done this today thought I would provide my 2 cents on what I learnt.

Service manual does state 2.5l but despite my best efforts I managed only 2.2l - 2.3l. It states to leave upright when filling but does not say what position to drain but obviously, it's more effective lent on the side stand.

Removing the water pump drain bolt, air bleed bolt and reserve tank siphon hose will allow it to fully drain properly. Once drained I poured half a litre of water in to wash away the dregs. Replenishing the system used almost exactly 2l and the reserve tank a further ~250ml.

I found it difficult to locate the siphon hose initially but it's actually very easy. At the bottom of the reserve tank, left side, probably hidden behind several other hoses. Once pushed aside you should see it clearly. Images below for reference. I used Putoline Ultracool 12 coolant, I also have 700ml left if anyone UK based wants it to save buying a third bottle. Pay postage and it's yours! 👍🏼

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How did you remove and attach siphoned hose? Very hard to get to

Brammers · May 18, 2019

I didn't. I used a syphon to empty the expansion tank out, rinsed and emptied it in-situ.

J

Daniel · May 18, 2019

Premacy31 said:
How did you remove and attach siphoned hose? Very hard to get to

Do you have a stock exhaust? If you do, that can take up a lot of room in the area in front of it, try removing the front sprocket cover, it's directly behind the bottom half of it.

If you have aftermarket exhaust, should be able to access it from the angle shown in my photos. It does have a small silver hose clip on it if you can pinch and pull that you should be fine. Persevere, though it's not major if you can't remove it.

Brammers · May 18, 2019

He has a 2018, so the evap can will be an additional hinderance.

I removed all the coolant via the fill hole.

J

Enrico · Dec 29, 2019

rustyeyed said:
Word of caution: Coolant needs to be non silicate and compatible with Mag alloy engines.

Is engine Mag alloy ?!
p.s. this was the post I referred to re coolant top up.

Magdiel · Jan 17, 2020

Daniel said:
Having done this today thought I would provide my 2 cents on what I learnt.

Service manual does state 2.5l but despite my best efforts I managed only 2.2l - 2.3l. It states to leave upright when filling but does not say what position to drain but obviously, it's more effective lent on the side stand.

Removing the water pump drain bolt, air bleed bolt and reserve tank siphon hose will allow it to fully drain properly. Once drained I poured half a litre of water in to wash away the dregs. Replenishing the system used almost exactly 2l and the reserve tank a further ~250ml.

I found it difficult to locate the siphon hose initially but it's actually very easy. At the bottom of the reserve tank, left side, probably hidden behind several other hoses. Once pushed aside you should see it clearly. Images below for reference. I used Putoline Ultracool 12 coolant, I also have 700ml left if anyone UK based wants it to save buying a third bottle. Pay postage and it's yours! 👍🏼

View attachment 2088

View attachment 2089

Did anyone try to use suction in order to empty the reserve tank?
I am planing on replacing my coolant and I was thinking about using the hose and air compressor I use for bleeding the breaks to empty the reserve tank instead of going through the hassle of removing it.
Magdiel

Brammers · Jan 17, 2020

I syphoned the old coolant out after failing to remove the tank. Put some clean coolant back in the tank, shake bike, empty again. Close enough(tm).

J

mc_enthusiast · Jun 29, 2022

I am doing my first coolant replacement on a CBR650F. The Honda factory service manual indicates removing the water pump drain bolt to drain the old coolant, which I did. I had the bike on the side stand thinking this was the best position to drain all of the coolant. Just to be sure, I held the bike upright. As I did this, more coolant began draining from the water pump. Then I removed the air bleed screw on the left side of the radiator. To my surprise, coolant began draining from this opening. It seems removing only the water pump drain bolt does not drain the coolant in the radiator. The Haynes manual indicates removing the two lower hoses from the radiator to do this. As I did this, more coolant drained from each side. I had a difficult time removing each of these two hoses. There isn't much room for my hands to work the hoses off of the radiator. With the hoses removed and pouring distilled water into the radiator to flush it out, it seems to run out of the right side only of the radiator. In looking at the picture of the flow of coolant thru the system in the factory service manual, this seems to make sense as it appears the water would have to circulate thru the engine before entering the radiator on the left side. I normally will fill the system completely with distilled water and take the bike for a ten mile ride to open the thermostat to flush out all of the old coolant. Then drain it all out and refill with new coolant. However, I am uncertain I want to fight getting the two lower hoses off the radiator again. I may just refill the system with new coolant and call it good. Will see how I feel in the morning. I will follow up this post with how much new coolant I can get in the system. The factory service manual indicates the following capacities: engine and radiator: 2.6 qts; reserve tank: 0.22 qts.