• Welcome, Guest! We hope you enjoy the excellent technical knowledge, event information and discussions that the BMW MOA forum provides. Some forum content will be hidden from you if you remain logged out. If you want to view all content, please click the 'Log in' button above and enter your BMW MOA username and password.

    If you are not an MOA member, why not take the time to join the club, so you can enjoy posting on the forum, the BMW Owners News magazine, and all of the discounts and benefits the BMW MOA offers?

Coolant replacement

chrismiii

R1100RT,K75,Burgman650
Has anyone attempted to replace their coolant themselves yet? It seems odd that the bike requires a special machine to just replace this. I have a 2014 RT and it’s been a fantastic bike! My 3rd RT.
 
If it is like the Wedge K engines, the only way to get the air pocket out is a vacuum tool. Burping the system will still leave a void in top of engine.
The radiator is lower than the top of head. No biggie, the tool and process is not hard after the first time and can be done in a home shop.

My understanding of the R is it is such a minimal amount only cooling the head, it should last a long time between needing attention. The early Wetheads and the dribble from the weep hole of the water pump for some seemed to be a source for needing a top off. Other than that...where could it go?
 
Water Pump Leak

My understanding of the R is it is such a minimal amount only cooling the head, it should last a long time between needing attention. The early Wetheads and the dribble from the weep hole of the water pump for some seemed to be a source for needing a top off. Other than that...where could it go?[/I]

Just a FWIW.... At my 6000 mile check a couple months ago, the tech identified my H2O reservoir was down to 1/4 and determined the water pump on the '17 R1200 GSA was leaking. He said a small amount of seepage at the weep hole is normal, but in warranty, BMW calls for the pump to be replaced if the reservoir falls below a certain point. This of course required removing the front of the engine case to access the pump, which meant a "free" oil change.
 
During this "downtime", I'm going to make a vacuum coolant filler for my GSA and do a coolant change while doing other maintenance items. I know it's supposed to be lifetime coolant but I'll change it anyway.

A rubber stopper with a hose barb, a couple of hoses, a couple valves, and my Mityvac. I already have all of these things.

I figure a vacuum is a vacuum weather its accomplished with an air venturi or with the hand pump.
 
ShopVac?

Do you have to vacuum out the old coolant (seems a shopvac would do that) or vacuum-draw the new coolant in? Might still be able to do that with a Shop Vac, some hose and duct tape :).

Every other vehicle I have ever seen with aluminum heads and/or block has warned you to change the coolant at some interval (i.e. - 3 years) as the anti-corrosion additives in the coolant break down. I believe it will still act as an antifreeze, but aluminum (head seems to be worst place, due to higher temperatures) will be dissolved/corroded over time.
 
The objective is to create a known vacuum in the coolant system, hold and monitor that vacuum for a period of time to assure there are no leaks and the system will hold pressure, then expose that vacuum to the fresh coolant mix so that it is drawn in without leaving any voids. The tool for doing it can be homemade if one has the skills and access to the right parts and tools, but ready-made kits to do the job are available from Amazon and other vendors and can be reasonably priced fur no-frills models like this one, which is very similar to the one I use. Vacuum fill is pretty much essential on the wedge-k bikes, but I can’t speak to the wetheads as I haven’t changed mine yet. But given small passages and heavier cooling loads the risk of trapping a void and creating a hot spot makes the correct tool worth the price to me. The brick-k engines were easy to fill and burp; not so much with the newer designs.

Best,
DeVern
 
Every dealer I ask tells me lifetime on coolant. Once I get to 4 years I will try to do it.

It cant be rocket science. Drop hoses drain everywhere you can, fill warm up and burp using the hoses.

We did it on the LT and yes sometimes we would trap some air but it would come out burping it. No different then a car to do IMHO.

I see no need for any vacuum or pressure devices other then to run you into the dealer to lighten your wallet.

I just checked mine and it was all but 4 oz down. It was at the min line and I filled it to the max line.

I bought a gallon at a BMW car dealer. I mix 50-50 distilled and anti freeze. I mixed 4 and 4 so saved the 4 oz mix in a water bottle to have it.

Again they say lifetime but I am always suspicious of "lifetime" stuff.

I asked my dealer as well and while they said "BMW" says its lifetime they suggest changing it at about 4 years.
 
changing rad fluid

Looked into this a year ago. It seems that most car manufacturers are now recommending the rad fluid be changed using the vacum method. The equipment is less than a 100 dollars, the cheapest I saw was about 70. While water does not wear out the inhibitors and lubricants do and the fluid does collect debris. I choose to just change the fluid in the right side radiator as it is located above the head and their is no way you could get air into the system. Its not ideal but gets some new compounds into the system. Done yearly or every other year it would work out about the same. I have to buy the device, I can use it on my other vehicles but due to moving never got around to it. Now that I'm settled in again will get one.
 
I have used a "Top Sider MVP vacuum pump" for all kinds of stuff, and it mite work for this also. I think I paid about $50 for mine, and have used it to suck out many different fluids. It can even fit down a dipstick tube if you overfill oil. Before I bleed brakes I use this tool to empty the reservoir and add new fluid. I have also used it to empty the radiator over flow on my cages.
 
I'm going to drain the system conventionally and refill with the vacuum (Mityvac). Also described this way in my BMW service cd.

One big reason to make my own... the "regular type of vacuum fillers won't fit (or easily fit) on the radiator neck without taking off the body work. The one I'm making will easily fit by only removing the radiator access cover.

The BMW instructions recommend a -.8 bar vacuum. The Mityvac easily meets this requirement.
 
I'm going to drain the system conventionally and refill with the vacuum (Mityvac).

Will it create the required vacuum and hold it long enough?
Are you going to use a small hand pump mity vac or one you attach to a air compressor?
 
I'm going to drain the system conventionally and refill with the vacuum (Mityvac). Also described this way in my BMW service cd.

One big reason to make my own... the "regular type of vacuum fillers won't fit (or easily fit) on the radiator neck without taking off the body work. The one I'm making will easily fit by only removing the radiator access cover.

The BMW instructions recommend a -.8 bar vacuum. The Mityvac easily meets this requirement.

Craig,
Please document what you make and how it works for you. Maybe a picture/video or two. I have a compressor operated Mityvac and I would sure like to change my radiator fluid in the near future - though a dealer did that during a water pump replacement during the "weepy" period a couple of years ago. Thx
 
Sorry I didn't get back to the forum sooner but I was in the garage - changed the oil and coolant, flushed the brake fluid F & R, and dropped the final drive. I should get the moly powder (cost 9 bucks) tomorrow to make my moly paste to coat the splines and will change rear gear lube.

The vacuum refiller I made worked like a charm. I'll take a pic of it (it's not pretty! LOL) but it's too late for a video. Sorry.
I used my hand pump Mityvac, a soft rubber stopper #6 size, a few hoses, and an old CO2 kegerator distribution manifold I had from when I was a homebrewer. Just stuff I had laying around. I was able to refill without removing anybody work other than the access door.

The BMW cd manual calls for minimum -.8 bar (-24 inHg) vacuum. The hand pump pulled about -28 to -29 inHG. Before opening the coolant line to fill, I let the apparatus sit for about 15 minutes to see if it held vacuum. No problem.

I'ts surprising to see how little fluid actually drains out from the rads and head. There is only about 1.5 l of coolant in the entire circuit according to the manual.
So barely a "wethead".
 
Sorry I didn't get back to the forum sooner but I was in the garage - changed the oil and coolant, flushed the brake fluid F & R, and dropped the final drive. I should get the moly powder (cost 9 bucks) tomorrow to make my moly paste to coat the splines and will change rear gear lube.

The vacuum refiller I made worked like a charm. I'll take a pic of it (it's not pretty! LOL) but it's too late for a video. Sorry.
I used my hand pump Mityvac, a soft rubber stopper #6 size, a few hoses, and an old CO2 kegerator distribution manifold I had from when I was a homebrewer. Just stuff I had laying around. I was able to refill without removing anybody work other than the access door.

The BMW cd manual calls for minimum -.8 bar (-24 inHg) vacuum. The hand pump pulled about -28 to -29 inHG. Before opening the coolant line to fill, I let the apparatus sit for about 15 minutes to see if it held vacuum. No problem.

I'ts surprising to see how little fluid actually drains out from the rads and head. There is only about 1.5 l of coolant in the entire circuit according to the manual.
So barely a "wethead"
.

OK, we'll start calling it a "damp head".:wave
 
A step by step description of your process would be most helpful to folks on this forum. Thanks in advance!
 
1. Drain the cooling system as described in the service manual.
2. Close the left valve. Open the right valve. Insert the correct tube (labeled in pic) in the gallon jug of coolant which is hung above the bike. I hung it from the door opener.
3. Use the Mityvac to suck the coolant into the tube from the rad filler/plug end. Close the right valve when full.
4. Push the soft rubber plug into the rad filler neck. The size of this plug sealed against the flat bottom of the neck so I did not have to pinch-off the overflow hose.
5. Connect the Mityvac to the correct tube (labeled) and open the left valve.
6. Operate the Mityvac to pull a vacuum on the cooling circuit. Close the left valve and let the system sit for a bit to assure the vacuum holds.
7. I held the plug with one hand while operating the Mityvac to keep the plug seated until the vacuum took over. I later learned this was unnecessary but it couldn't hurt to hold it tight against the neck.
8. Slowly open the right valve and the coolant will be sucked into the circuit.
9. Let it run until the coolant stops flowing.
10. Drink beer
11. As it says in the BMW manual... you may have to top up the coolant after removing the plug. I had to add maybe an ounce.

I should have trimmed up the length of my tubes to better fit where the valve manifold was located by the right-side bar grip but this is how I cobbled it together this morning and I didn't feel like changing it. A #6.5 or #7 rubber plug may fit easier but then you'll probably have to plug the rad overflow line. This is a #6 plug actually inserted upside down; but this is the plug I had. You'll find these plugs at any decent homebrew shop. My tubes were so snug fitting on the barbs, I only needed one hose clamp.




vacuum.jpg
 
Last edited:
A step by step description of your process would be most helpful to folks on this forum. Thanks in advance!

My process is similar but a little different :dance

  1. Start bike
  2. Ride to dealer
  3. Ask for Coolant Flush Service
  4. Eat a donut and have free coffee
  5. Get back on bike
  6. Ride home
 
Back
Top