Head's up - F800gs Rad' fan vulnerable.

Just to let you know the radiator fan on my F800 GS swallowed a some grit & dirt & died. $420 & only a week later with very little dust & dirt inbetween the new one was clogging too until I intervened with some WD40.

Seems like there may not be enough protection around the fan bearings to stop the ingress of dirt.

Just so you know to invest in a can of WD.

Slippy

This is actually a pretty well known topic. I haven't bothered to search but it has been discussed here.

The fix is to periodically reach in and give the fan a turn to ensure it is not stuck.

Flowing some water through the radiator and fan area forward and backwards will clean it out.

I would stay away from the WD. You will attract dirt with it.

If you let your bike sit until the fan kicks in you can easily confirm its operation. If it does not kick in when it is suppose to you will get an oil light blinking on the dash.

Why did you pay? Not in warranty any more?

My fan on my F650GS twin got full of road tar & rocks last fall (idiots repaving roads without warning signs). When it tried to spin and could not, it threw a check engine light (MAL).

The error code was reported by GS911 was:

10442: Fuse activated for component block 1 (O2 sensors, Fuel Evap control valve-if fitted, and additionally secondary air valve, fan motor for K- and F-series)

Basically the fan tried to draw too much current (it was stuck) and the controller shut it down (hence the fuse activated though it's not really a fuse).

Note that the error light disappeared after turning the bike off and on again, since the fan did not come on right away.

Little clue for those that have this in the future.

---

Now that being said, I wish someone would make a cage/guard for the thing to prevent pebbles from getting in there.

Cheers
Tim

Sage advice. Mine was somewhat locked up. Got the oil ight while sitting at a light after a high-speed run on a 90+ degree day. Got home and let things cool. Gave it a turn manually and it felt stuck then "gritty". Spun it around a time or two then heated up the bike. Once up to temp, the fan made an awful squeal and kicked on. Been working fine ever since.
Just be mindful of it and pay some attention.
Ride-on...</snip>

What everyone else said, give it a spin by hand when it gets stuck. The bearings are not lubricated near as I can tell but last just fine.

Rocks in the shroud, certain types of fine dust, and months of non use will cause them to stick however till manually rotated.

You might go back to the dealer that replaced the fan and inform them of this as they probably did not knowingly replace a good part but are simply unaware.

It's not intuitive and BMW literature does not really mention it.

Mine is a 2008 European edition & out of warranty by a month, therefore the credit card took the strain.

Now that I know I'll keep a close eye to ensure I don't have a repeat.

The joys of motorcycle travel eh!

I was sitting at a light today and when I looked down at the gauges the engine light was on and the oil light was flashing. Searched around here to find out what might wrong and sure enough the fan was stuck! Always great info here!

Was stuck in traffic on the highway after a day on the trails, freezing my butt off in the cold and rain when I look down and the oil light is on. Had a vague memory of a thread on advrider talking about the light would come for more than just low oil pressure like one would assume. Pulled over on to the shoulder and switched the bike off and back on. As soon as the bike restarted the fan came on. Light never came back. I am in the habit of manually giving the fan a spin since I read they can get stuck and have found on a few occasions it has been hard to spin initially but this is the first time I've seen the warning on the dash. Thanks again advrider!

My fan was WAY too close to the radiator and was actually rubbing it.:eek1 Loosened the bottom mount screw, installed a plastic washer underneath the fan and secured it with the bolt.
Turns fine now, but at first I though the bearings we're going out on it. Might be worth a check.....

I'd want to check to see if you didn't bend or break the plastic rad mounts.

Same issue with the fan. Alerted by the blinking oil light after a long run followed by a long idle. A bit worrying at first but remembered something about fashing oil lights and over temp. After stopping for a few minutes and re starting everything was OK. Later checking of fan showed it appeared seized on the radior core. After manual turning and a good bow out with air the fan freed up. No obvious evidence of small rocks that may have been jamming it. Following another run on gravel roads the problem has re occurred. Think I will try the spacer solution as the sound made is more that of the fan (or gravel between blade and core ) than a dicky bearing.

I didn't bust anything, but I did run back outside and check them after I read your post.

So, do I assume that if there are no warning lights showing up on the display, that my fan is working normally?. I tried to test out my fan the other day, tried to 'force' it to come on but I couldnt do it.

Seems to take a bit to get the fan to run - a fast run in warm weather and then iding for a few minutes. I would't be suprised if many F800 fans don't work at al over winter in Aus !

Delved into the fan on the bike and removed it after removing beak and "tank" for better access. I found that it is definitely not scraping on the core (over 10mm clearance here) or gravel between the shroud - (there is about 3mm clearance here). It is the fan motor. it will turn, then stick with a gravely feel. Then spin freely ony to lock again - I will get some sparkies to look at it to see if it is salvageable.

I had this same problem too. I dismantled the whole radiator setup to let it hang on hoses (not a big task). By that I could get easy access to loosen the fan setup. The problem was that there was dirt (tiny rocks and dust) between the join of the propeller and the fan motor frame. The join is so tight that even small amount of dirt can stuck the propeller. I suppose this might be the main target for these problems.

f you have access to a GS911 tool it has a function to test the fan. I run the test every service cause I doubt it comes on often. The "exercise" program seems to work. No fan problems in 45000 miles.

Exercise is the key. Not only does crap build up in the shroud, deposits such as clay and salt stick the shaft to the seal, exercise helps avoid all.

The cooling fan on the F8 is nothing to write home about, but it's not a bad one, middle of the road in my opinion.

What is causing problems more then anything is that the cooling system is so damn efficient and oversized. I suspect there are owners who's fan hasn't come on in years.

Even without a gs-911 or MOSS, the fan is easy to exercise.

While the bike is cool (unless your hands are fire proof) reach behind the radiator and spin the fan. If it is stuck, flow some water from behind the radiator. Full pressure from a garden hose shouldn't hurt anything. Try rotating it again.

Once the fan rotates freely, and in either case, once a month I would suggest, warm the bike till the fan activates. You can do this from cold or after a ride. simply point the bike out of the wind and let her idle. The fan will activate from freezing in about 12 minutes, quicker if its warmer or after a ride.

I have seen many many stuck fans, but none I couldn't free with some water and manual rotation them.

I have also seen some declared dead by dealers on bikes that were out of warranty. Never had a problem freeing them back into working condition either.

This didn't help mine since there where those tiny rocks as I explained (or at least tried to explain) in my previous message and they didn't come out by rotation and water spray (and I was a bit scared to spray water to fan motor). Propeller rotated but was tacky. The only way to make it rotate freely was to dig those tiny rocks out of the join.

Hey guys, im putting some life in this old thread.

So i tried to get my fan running yesterday, the radiator gets warm and all, but the fan wont start.
I let the bike stand running for like 10 minutes. It was about 20 degrees C outside, so pretty warm for our climate. But the fan doesnt start.

When i spin the fan by hand theres no problem, it spins as it should.

Is there some easy way of testing the fan?
If the motors blown or soemthing like that..

Find fan connector, add 12v, fan should spin.

More likely the thermal switch has gone.

Pete