Rattling Noise on Roomba 500 Series

THX-1138 · Post by **THX-1138** » September 3rd, 2007, 3:10 pm

Some of you that own the 500 series have reported a 'rattling' noise when cleaning. This noise becomes more noticeable during hard floor cleaning. I have the same issue and decided to inspect this further. I have noticed that accumulated hair was able to get past the 'end caps' and under the bearings! Similar to how it was on the original pre-swivel front wheel Discovery series!
I removed the accumulated hair and ran the Roomba 560. This time around it ran quiet as a mouse! Something else to note, the new non-slip bearings design is great for them to not get lost but it creates a hair trap again! Back to square one for this issue. In conclusion, please check under your bearings and on the ends of the brushes for accumulated hair. If you have any, remove them and observe if the rattling noise has gone away. Please report back with your results! Your efforts are appreciated!

franks59 · Post by **franks59** » September 3rd, 2007, 3:43 pm

Ok, here's some interesting results:

First I inspected the end caps but did not find any hair. I cleaned the brush as thoroughly as I could. I ran it on harwood and it still had the same rattling noise.

Next I removed both the brush and beater bar and ran it. The rattling noise was gone.

I replaced only the brush and ran it. The rattling noise was still gone.

I took out the brush and replaced the beater bar. This time when I ran it, the rattling noise returned.

And finally I replaced both and ran it. The rattling noise was still there.

So for my 560, it's the beater bar causing the noise.

Frank

Post by **Fraggboy** » September 3rd, 2007, 4:01 pm

I noted in my Review(Going to be posted soon), that my cat hair got around the brush caps, and ended up between the brush ends, and where it connects to the deck gears. The Scheduler trapped the cat hair around the brushes which was fine. With the 5xx series, one will have to pay more attention to this, cause hair has the chance to enter the deck. One would have to use light-duty oil, and/or start shimming.

THX-1138 · Post by **THX-1138** » September 3rd, 2007, 4:17 pm

Frank,

Did you check for accumulated hair under the bearings? Not just the end caps. Could be that there is hair on the beater bar bearing.

Fraggboy,

Shimming and oiling is to reduce the wear on the housing due to the vibrating caused by the brushes. Hair accumulation on the ends will result in high friction which causes plastic meltdown, introduction of hair inside the gear box which also causes premature wear and introduces pressure that pushes against the brush end. Definitely this is not good news. I spent some time trying to analyze what is causing this and found out that the change factor was on the new 'bent' brush design and particle bin hair teeth. The new bent brush design AND particle bin hair teeth are creating the effect of pushing hair towards the ends of the brush. This in turn will bypass the brush end caps which end up on it's extremes (brush ends).

Solution would be to re-design the main brush and probably remove the particle bin hair removal teeth (or position them differently).

vic7767 · Post by **vic7767** » September 3rd, 2007, 4:51 pm

Although I don't have the rattling on my 535 I have noticed additional hair buildup at the ends of both brushes that did not occur on my Roomba Reds. Debris being forced to the edges of the brushes and not sent to the collection bin is now leading to extra effort to clean the tdeck brushes.

THX-1138 · Post by **THX-1138** » September 3rd, 2007, 5:01 pm

OK, so this phenomenon is more like a design flaw or oversight. iRobot needs to know about this ASAP. Let me start writing them.

Post by **Fraggboy** » September 3rd, 2007, 5:15 pm

THX, I know what shimming and oiling's main purpose, but if the shims close the gap, the hair has a harder time getting in.

Vic, I was thinking exactly the same thing. More attention needs to be brought to the ends of the brushes, and the deck. This will in fact cause issues for the people who don't clean out their Roomba on a regularly basis.

THX-1138 · Post by **THX-1138** » September 3rd, 2007, 5:38 pm

Correct, harder for the hair to get in. Though with the current vast amounts of hair being collected at the ends will make shimming an almost lost cause.

franks59 · Post by **franks59** » September 3rd, 2007, 6:02 pm

THX-1138 wrote:Frank,

Did you check for accumulated hair under the bearings? Not just the end caps. Could be that there is hair on the beater bar bearing.

I'm not sure how I do that. The area between the red part and the yellow part is clear of any debris. I don't see how to remove the yellow "cap" surrounding the axle to check for hair.

Has anyone been able to reproduce my results by testing each brush?

[EDIT] Attached blurry image of end of brush.

Frank

Post by **Fraggboy** » September 3rd, 2007, 6:17 pm

Frank, there are little "Nibs" on two sides so you can use your fingernails to pull off the yellow bushings.

scooterboy · Post by **scooterboy** » September 3rd, 2007, 6:18 pm

franks59 wrote: I don't see how to remove the yellow "cap" surrounding the axle to check for hair.

Look for the two sides of the hexagonal nut that are indented and squeeze those two side (hard) while pulling. The endcap will come off.

Twice so far (in less than a week) I've removed those endcaps and found a nice nest of hair under the beater bar endcap.

bjv · Post by **bjv** » September 3rd, 2007, 6:46 pm

Frank, with my 535 I get results similar to yours, but not completely identical. I too have rattling (almost grinding) noise only when on hard surfaces.

I removed both brushes and ran it and the noise disappeared.

I made sure both brushes were clean, ends were clean, and there was no dirt under the end caps and tried it with one brush at a time and found I get the noise no matter which brush is in, although it seems to be louder with the beater brush in, in my case.

franks59 · Post by **franks59** » September 3rd, 2007, 6:49 pm

Ok, thanks Fraggboy, scooterboy. Got them off. They're completely clean underneath, Rattling persists.

Frank

vic7767 · Post by **vic7767** » September 3rd, 2007, 7:04 pm

franks59, if you have an older model Roomba around try swapping out the brushes. I just took the bristle brush off of a Roomba Red and installed it into the 535. Fits perfectly still manages to dump debris into the dust bin and the hair collects more uniformly that heading to the two ends of the brush.

See if the brushes from a 4th gen are quieter than the 5th gen.

franks59 · Post by **franks59** » September 3rd, 2007, 7:23 pm

vic7767 wrote:See if the brushes from a 4th gen are quieter than the 5th gen.

Thanks for the suggestion. The beater brush from my Red and Disco both are smaller in diameter than the 560, but fit the 560. Both ran with an extra, somewhat high-pitched noise. However the noise was consatnt and there was no rattle.

This seems to confirm that there is a problem, but I don't know if it's the brush itself or the motor that controls the brush.

I wonder if there's a separate motor for the beater brush.

frank

jubrand · Post by **jubrand** » September 3rd, 2007, 7:24 pm

With mine at least, the rattling seems to just be from the new wheel style on the front when it is on bumpy tile. It did it the very first time I ran it with a perfectly clean roomba. Small price to pay for the overall quietness of the new ones though.

THX-1138 · Post by **THX-1138** » September 3rd, 2007, 8:06 pm

Both the beater bar and brush run from the same motor by using a gear box.

The rattling noise comes back after clearing out the hair but less often. Will try the separate beater bar and brush test.

Another thing to consider is that the beater bar is touching the hard surface much more than previous generation Roombas. I'm going to add some talc powder and test if it makes the noise. The brand new rubber on the beater bar could be rubbing the hard surface more so and causing the noise. Vic's test with older brushes sounds like also something to check out....wow, to many tests.

geekgranny · Post by **geekgranny** » September 4th, 2007, 11:41 am

My two are making the "noise" too although one does it more than the other. I too have much more hair making it to the ends.

I noticed when cleaning the brushes, very little accumulation on them, the first few times, on rubbing, with my fingers to clear the hair, the white area "housing" where brush/beater fit in, I noticed some light oil. So it appears that iRobot did oil them some.

I've described the "noise" that they make on my tile, to have some similarities to a rattling "rubbing" sound.

I took one to a friend of a friends house yesterday to work while I was doing some work there. Her carpet "looks" pretty clean, but was loaded, with big dog hair "tumble weeds", up to 5 inches or more

, around the tile edging of room and under some furniture.

In her hallway, short cut pile it made a noise unlike what I've had here on my tile.

On her Berber it didn't make any of the noises (that I noticed).

BTW.... she has one large area rug on her Berber with 4" very fine fringe and two smaller ones on her ceramic tile with same fringe. 535 never even snagged any of the fringes that I saw.

One thing it does do that the others Disco/DirtDog don't is when the 535's run over an area of lots of spilled, over a cup pile, of small doggie kibble the kibble rattles around a lot. It was so annoying I had to stop it to empty the bin.

I was asking, in another thread, about removing the front wheel. My doggie hair accumulates around the recessed area there. The instruction manual says you can remove the whole wheel assembly by pulling it out with your fingers. It isn't that easy though. I have not done it yet but theres bound to be some hair under it. I'll probably have to use a screwdriver under the edge, not the axle part, to gently pry it out some as I can not get a good hold on it to pull out.

gg=alice

franks59 · Post by **franks59** » September 4th, 2007, 1:53 pm

geekgranny wrote:My two are making the "noise" too although one does it more than the other.

gg, have you tried removing the brushes one at a time and see if the noise goes away?
On mine when I remove the beater brush, it is completely free of any extra noise.

Frank

geekgranny · Post by **geekgranny** » September 4th, 2007, 2:24 pm

franks59 wrote:
geekgranny wrote:My two are making the "noise" too although one does it more than the other.
gg, have you tried removing the brushes one at a time and see if the noise goes away?
On mine when I remove the beater brush, it is completely free of any extra noise.

Frank

Thanks Frank, I will do that today (after my trip out to see if my Costco or BBB or LNT have 5xx on shelves yet). The DirtDog "pack" is doing the pre-cleaning now.

gg=alice