Coolant replacement procedure

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Martin J
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Coolant replacement procedure

Post by Martin J »

Hi, I've just carried out my first service at 520 miles, changing the oil, cleaning the strainer (which had a few bits of swarf on it!) and checking the rear diff oil.
While I had the tools out, I decided to change the coolant for 5 year life stuff instead, draining it via the bottom rad pipe. However, I cannot see how the expansion tank supplies extra coolant to the radiator to replace any bubbles, as it just has one pipe leading to it from the radiator neck. I filled the radiator to the top and ran the engine for a few minutes, blipping the throttle before replacing the cap, but I don't feel confident that all the air has been expelled from the system.
Is this the correct procedure, and am I concerned about nothing? Or are there any other steps I might have missed?
Yamaha 900 Diversion '96
Suzuki GS550E '81
Benelli TRK502 '21
Honda PCX 125 '18
springer1
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Re: Coolant replacement procedure

Post by springer1 »

Fill the coolant system radiator & overflow tank to the proper level. As the coolant system heats up any air will be expanded out thru the hose to the bottom of the expansion tank and bubble up. When the scoot is turned off and cools fluid from the expansion tank will be sucked back via the same hose into the radiator. Assuming you filled the radiator and cooling system, any air that was in it will have been purged out and replaced by overflow coolant. Be careful you used the correct coolant as any that has silicones or any other abrasives will quickly ruin your seals. Watch the level of your overflow and replace any that was sucked into the coolant system.
Martin J
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Re: Coolant replacement procedure

Post by Martin J »

Thanks for the info. I'm pretty fussy about servicing and getting everything just right, so maybe I'm worrying about nothing.
Anyway, I took my scoot for a good run tonight and everything was fine. The level in the header tank was just above max when I got home due to the expansion of the coolant when hot, so all is good. Plus the red coolant is much easier to see than the original yellow stuff.
Yamaha 900 Diversion '96
Suzuki GS550E '81
Benelli TRK502 '21
Honda PCX 125 '18
springer1
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Re: Coolant replacement procedure

Post by springer1 »

Sounds good !
Lafree
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Re: Coolant replacement procedure

Post by Lafree »

So bang goes your warranty using non recommended antifreeze ?.
Martin J
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Re: Coolant replacement procedure

Post by Martin J »

Lafree wrote:So bang goes your warranty useing non recommend antifreeze ?.
Honda specify non-silicate coolant, which it most definitely is! :)
Yamaha 900 Diversion '96
Suzuki GS550E '81
Benelli TRK502 '21
Honda PCX 125 '18
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