Your motorcycle's cooling system: How it works, and how to flush it! 

Nice video. Couple fine points you may want to consider: 1) Instead of simply running the engine for an arbitrary amount of time (in this case, 10 minutes), I always run the engine for at least ten minutes after the thermostat has opened. If you don't allow for sufficient time after the thermostat opens, the flushing agent will have cleaned the engine block but not the radiator, so the entire system won't be a clean as it could be. 2) After draining the flushing compound out of the motorcycle, use caution when adding fresh water. Always use warm or hot water; never add cold water to a hot engine, as you risk cracking the block. (Incidentally, hot water also contains less dissolved solids as well, since the solubility of hardness ions (Ca+2. Mg+2 and Fe+2) is inversely proportional to temperature, which is why scale forms in your hot water heater and also your engine block if you don't use distilled water for the final coolant mixture) 3) The crush washer that you said is in fine shape has actually been crushed at least 4X by the end of the video; once before you began, twice after you drained the old coolant and reinstalled to fill the engine with flushing compound, three times after you reinstalled to fill the engine with plain water, and four times as you reinstalled prior to adding new coolant. Although it's fine to reuse the crush washer during all the steps shown herein, I always replace aluminum crush washers after one use and anneal copper crush washers before reusing. Annealing copper washers is easy; simply heat the washer to cherry red, followed by quenching in cold water. The annealing process relaxes the internal stresses in the previously "crushed" metal, allowing you to reuse over again.

Just bought my first GL at 68 years old, its a 75 GL1000. Found this really helpful as are some of the posted comments. Thanks, Jim

Great video! For the negative ninny, they obviously didn't pay attention to your immediate flushing. On top of that, the flush chemical will only get to deposits on your aluminum and rubber parts temporarily. Vinegar as a part of the first flush will nullify the acid prior to the final flush. Honda engines and drive trains do have sensitive parts but are more bullet proof then any other manufacturer. Remember you are doing preventative maintenance and any thing you do to extend the engine components life is always for the better. Thank You for the reminders of things I'd been skipping like flushing the over flow reservoir. Hoka Hey

DAMN. I have a 99 1500 same as yours. With 52.000 miles. And have never changed the coolant !!! Time for a Change!!!

WingAdmin! As always, your tutorials are the best-well explained, well illustrated, some humor. Makes me sort of miss my winter Gold Wing projects. Thanks for reminding me to follow this channel.

I don't have a goldwing. I did not watch this video for a street bike. However, I learned quite a bit and very useful for what I am doing with my Honda XR650R. Thanks for a great informative video. Very well put together. Cheers.

Just bought coolant last night... 10 bucks a quart... damn they are proud of that coolant.

Best introduction and instructions

Good video, great website. The only thing I’d add is, the ‘last’ step should be documenting the procedure in your logbook. Both date and mileage.

I assume the job is about the same on a 1800 so I'm glad you take the time to help us understand how to do our own maintenance - thank you!

Very nice and clear tutorial on the system cleaning. Last summer I accidentally came across a very inexpensive mint condition 1993 1500. Very much loving getting on the road with it. I've had many Big road bikes since 1971, including 3 GWs (1200, '01 1800, HD Ultra,) now the 1500. Thanks again for all the great content on your channel. Thank you Scott. Jack

Hello, I have always wanted and have recently bought a 1997 GL 1500 SE. Great videos, well explained and clearly explained.......thank you and keep up the excellent work.

Thank you for your video and your information, you did not have to get to the motor problem, simply by talking and saying certain cases of motor problems. I was able to understand that one of those cases was mine and thanks to you I can go directly and repair the problem of the hose that was broken.

First time on your site. Great job and I'm looking forward to digging deeply into your posts.

Excellent, thanks. Unfortunately, my wife walked in during the part you were pumping out the reservoir contents into a bottle between your legs. That took some explaining!

Great info about the coolant type. I had to get coolant while far away from home and didn't know that it has to be silicat free. Lucky for me, I picked up Havoline Universal Coolant. I keep the jug in my trailer, so I had to check immediately.

I did it on my 2015 last year... one thing you need badly is patience... 😉... now the reservoir is under the bike here... a lot easier

The Mr. Rogers of motorcycle maintenance

Good info as always. For the coolant I use Zerex (blue) Asian (recommended for Honda )it says on the label SILICATE & BORATE FREE, cost a bit less than 20 dollars per gal, while Honda is 20+ per quart.

very timely as I an about to tackle the coolant system on mine.

So Good! you explain things in a complete yet simple way that anyone can understand! I am you new subscriber!!!

Great video, and prestone is silicate free antifreeze. No need on paying $32 for a gallon of Honda brand. Which is a 50/50 blend. Which isnt made by Honda anyway. But i always buy the 100% antifreeze and use distilled water to make a 60/40% blend. 60% being antifreeze. And while following his 10 minute flush time. At 9 minutes my 1999 GL1500SE started really bubbling over and steaming out. Thought i had a thermostat problem. But i went ahead flushed and cleaned. Then added the 60/40 mix. Road it 20 miles, and it stayed cooler on a 95 degree day than it ever did. I was told by the Honda dealer after it got up close to the hot line. The week before, i had a air lock. Shes fine now with the flush and topped off antifreeze. LOVE THIS SITE!!!... And i book marked this site. subscr9ibed and saved! Thanks again guys.

Great video hope this works on my 2001 wing it’s overheating like crazy engine sounds fine but I suspect air in the cooling system and possibly the left fan isn’t turning on.

Did this very job today on my GL1500 Valkyrie.

The service manual for the GL1500 states that the cooling capacity is 4.3 quarts. Not sure if that includes the overflow tank quantity. Also, if you are flushing a cooling system, you will want the engine hot enough to allow the thermostat to open up for proper fluid flow through the engine/radiator. Typically, the thermostat will need to see 180 - 200 degree fluid before it will open. Then run the engine for 10 minutes or so. Also, you don't want to introduce cold water into an engine that has been running 10-15 minutes and then the coolant drained out. Best bet is to let the coolant flush mixture cool down before draining, and then add water. Another option would be to use at least room temp (70 degrees F) water or warm water. When I flush the coolant in my vehicles/motorcycles, I always do 2 rinse cycles to help ensure all of the chemical cleaning solution is removed. Also, if possible, remove the overflow reservoir, and make sure it gets cleaned properly as well as check the hose and connections for leaks, brittleness, cracks etc.

Thanks for the explanation i can understand

Great Video. Thanks!

Have you considered using Evan’s waterless coolant? Jay Leno recommends using it. Never need to change the coolant again. Also, there’s no corrosion. Thanks for all the videos and info on your website.

I recently changed my coolant and used Prestone but they only had one coolant that was compatible with the Honda engine and I had to special order it. So Prestone does have the correct coolant for your Wing but it may not be on the shelf at your local auto parts store but they will order it for you.

As always, thank you.....love the direction (MAG)

Hi goldwing doc's Thank you for the coolant flush video, if you haven't done a video on carburetor synchronizing for the GL 1500 can you do so please , it seems like I'm losing a little gas mileage, I have a four gauge carb synchronizing kit but the instructions are poor . Thanks again for your tips and techniques.

Good information thanks 👍🏼

Hey nice well explained video. Got a request though. Air ride system leaking bad and won't hold any air for more then a few seconds. Where to start?

great info, learned a few things, thank you very much

Hi Scott, i love your videos and i would like to ask you for a favor, would you do a video on synchronizing the carburetors ? I have a 99' 1500 SE 50th Anniversary model and some of the other videos i have seen on RU-vid just dont make it , i have a 4 gauge synchronizing kit and would like to see the proper way to do this. Yours truly William

Was 4 quarts enough for the radiator and the resevor it looked pretty close

Thanks for that , It is very helpful, Sir, If I may ask, Where about are you based on please , I may need your support sometime in the future

How do you replace the coolant resevoir on a gl1800

Great video thank you very helpful

Thank you !👍

awesome video! thanks man!

Regarding your using Honda coolant, oil filters, etc… exclusively: my Triumph dealer’s mechanic told me to use Triumph oil filters, no matter what oil I used. Factory parts keep the warranty intact. I hate it when people will spend thousands of $$$ on a motorcycle, only to use the cheapest oil, coolants and filters to keep the bike running.

Where your placing the funnel , i have a antifreeze tank ....which i believe its like having a radiator cap ...i can don the flush through the tank ....its like a white tank , 1986 honda goldwing, GL1200A, aspencade

Good job!

Thanks!

Would it be advantageous to run two rounds of flush cleaner through in order to get any residual gunk out and then do the water flush or do you think one round of the flush cleaner is sufficient? I just bought my GW (2004) and I have no idea if periodic maintenance was done at all.

@GoldwingDocs Re using automotive coolant in terms of principal, different model bike, though reference to that and your pump failing, the caveat maybe you hadnt't clarified, the potential that that coolant you had used, was not specifically silicate free? Just to clarify your experience and likelihood of root cause in that incident?

Do the false gas tank and the seat need to be removed to change the coolest for a 1984 Goldwing go 1100?

Hello doc! I have 1982 Goldwing 1100 Lehman Trike which I traded for my 2001 GL1800A! I'm just really trying to get the seat off so I can get things cleaned up underneath there! How do I do that?

Question here, have you ever used Hondas type 2 coolant in the Goldwing? It seems to be the exact same ingredients as the hp. It’s a little cheaper to get a gallon of the type 2 vs 4 quarts of hp. Your thoughts??

how is it that the Preston flush won't hurt seals and parts of the cooling system. the flush is acidic and corrosive.

Thanks great vid. But I screwed up i think....2013 R1...I drained the old coolant, flushed with distilled water with the drain plug off, then added 50/50 vinegar water and ran the bike with the system closed till fan came on. Then I rinsed by adding water with the drain plug out.. then closed the drain plug and added the new coolant. So I did not run the bike with pure distilled water, just rinsed with the drain plug out after the 50/50 step. Am I ok, or do I need to drain the new coolant and start again by running the bike with pure distilled water...then add more new coolant??

HI, IA HAVE AN OVERHEATING ISSUE WITH MY GOLDWING 1800 2008.... WHEN RIDING UP HILL, THE TEMPARATURE STARS TO RISE UP , AND I MEAN REALLY HIGH... BUT WHEN I AM RIDING ON THE CITY , THE TEMPERATURE STAYS NORMAL.... I CAN SOMEONE EXPLAIN THIS TO ME , IF THIS IS NORMAL WHEN RIDING UPHILL ! THANK YOU

Someone help me please. My coolant reservoir has a crack on the top, with the correct coolant level at the mid of it. The hose from the radiator connects at the bottom of the reservoir, where there’s a lot of coolant above it to suck. By any chance will it suck air from the crack which is well above the coolant level inside the reservoir?

6:15 this is never made sense to me, how can it possibly work. The coolant gets hot, pressure builds up and pushes the cap spring upward revealing the drain hose which leads to the reservoir. When the coolant cools down the pressure is relieved, the spring expands again blocking the coolant reservoir hose. How can the coolant possibly return to the radiator.

Hi where is located what album Goldwing 96SE 1500 Thank you

Good info - Thanks.

What is the correct radiator cap # for the gl1500? Thanks

What about flushing the resivoir ?

Maaaaan I wonder who are the 2 idiots that gave this man a thumbs down?

Great Scott! Job that is. :)

Hello Admin, my 1993 GL1500SE doesn't have a coolant resovoir. It was taken out. Just the radiator. Each time I fill up the water via the radiator, it boils and dumps water when hot (after running from 5-10mins). Also, what is the exact capacity of the radiator? Is it 3.5L/3.7L without the coolant resovoir?

awesome video .answered a lot of questions .l;g

distilled water

❤👍

Love your videos but you said never run your bike without coolant. Then you put only water in and ran for 10 minutes. Make that 20 minutes when you came back to drain it. ????

👀👂 👍☕

This guy has to be talking to the lowest common denominator of the human ladder. I live in North Carolina and there are people that fit that category here. There are plenty of candidates who will try to open a hot radiator cap because they just don't know any better; they're mostly farmers.

I would NEVER! use a flushing agent in my engine, it is acidic (Sodium Citrate)and will easily harm aluminum and seals. Even if it doesn't destroy anything, it will compromise the integrity of metal and rubber causing an eventual failure down the road. Also It can cause metals to become porous, creating a home for deposits and more corrosion. I only use distilled water to flush, run the engine... maybe even take it for a short ride... let it cool down. Drain and repeat. If your engine is really old and has never been properly maintained then more uncivilized methods would be used.

You're actually not supposed to flush motorcycle systems big guy. Any bike mechanic worth their salt will tell you this.

Sorry but the music so annoying, i can't hear well.