328 bobcat question..

hi to everyone
my boss just bought a 328 bobcat mini excavator,it's a 2006 model,it has low hours and everything seems that it was a good deal but a little after we noticed a weird noise when rotating (swinging).. the seller told us that needs some greasing because the previous owner(for 3 months) wasn't big fan of grease gun,he assured us that once we got it to work we will forget the noise...nothing seems to improve after greasing it a few times and now we are thinking that is maybe the rotation? bearing that causes the noise...should we go ahead and open it ourselves??the bobcat dealer can't give any advice by phone and the problem is that we are 1000 km away from them...any advice could be helpful since we have no experience on mini-x....
we also have problem with the users manual which is all in italian language and can't undrestand a thing..any chance to download a manual in english???

Do you have fitting directly on your slew ring bearing and that's what you've been greasing? You might want to grease the gear teeth on the inside of the slew ring. Also check the swing planetary gear box for proper oil level. I'm not sure how to get to these components on a Bobcat Ex, haven't worked extensively on them, I just know it's a PITA to get to anything on them.

thanks for replying..we didn't thought of the oil level..we'll see it tommorow...

I would of thought that the dealer should of greased the machine prior to selling it to your boss regardless of whether the previous owner had a love affair or an allergy to a grease gun!!

If the noise was caused by a lack of grease they should of greased and operated the machine to aleviate this prior to selling it on.

Hopefully there is not a major problem especially with the swing bearing e.t.c as that can be very costly to fix.

If there is a major problem which the dealer didn't mention then hopefully you will have legal rights to return the machine for a full refund as the machine is not fit for purpose e.g if it was sold in good/full working order and it actually isn't.

unfortunately the guy who sold the machine is just a trader...not a dealer..we made a call to the previous owner today and said that he just didn't notice any strange noise while using it..this makes the situation more complicated as we cant understand when this noise started finally..as you said if it was a grease problem it would be fixed right after greasing...concerning the cost of a new bearing wouldn't be such an issue but the problem is that we have to fix it ourselves and so we will have to remove cab/boom to have access to this bearing...and we are in a big hurry these days!!

hmmmmmm seems tha we need the help of an experienced mechanik in bobcats cause we can't find how to reach the oil of the swing planetary ...

Reference your Bobcat

I'm not that familiar with Bobcat excavators but I would suggest the following -

1 You can access the slew motor by removing the cab floor plate (pull out the rubber floor mat ).
2 Check the slew reduction box oil level (as has already been suggested).

3 Check to see if the bolts holding the slew motor to the reduction box are tight.

4 Check to see if the bolts holding the reduction box to the chassis are tight.

5 Drive the machine up onto blocks ( about 12ins /300mm) get underneath and with a torch check that the pinion gear shaft (from the reduction box) is not leaking and also check that there is not excessive movement on the pinion shaft bearings.

6 Get someone to position the bucket on the ground and slowly touch the bucket on the ground, if there is excessive wear on the slew ring you will see the movement, repeat this at 90 degrees, then 180 and 270 degrees. If your machine has low hours there should little or no movement on the slew bearing.

If you don't find anything wrong the my only other suggestion (without hearing the noise!) is that sometimes the slew motor brake can make a noise without causing any damage.

For Bobcat dealers in Greece go to www.bobcat.com

Regards

thank you very much for the help hanomag!today we got under the machine and checked everything you mentioned. nothing special to notice everything is tight and no leaking..then we removed the bottom of the cab and got to the slew motor,now we are sure,the noise comes from inside the slew motor!obviously the motor runs by the hydraulic oil.the hydraulic oil level is ok!the only thing to do now is to open the motor for a fault bearing..we 'll see.....THANKS EVERYONE for giving advice/information...

greetings from greece!!

Is there any vibration when slewing?

If not can you find a similar machine locally to operate/listen to - just to make sure that the noise isn't a 'feature' of the machine!!

no we can't notice any vibration..and yes there is also one 328 in my town and doesn't make this noise...we are about to open the motor these days...

the bottom bearing in the slew box gets noisy if there is play in the slew ring

Hello everyone. So is there gear oil in the motor??? or is it just part of the hydraulic system that is fed and operated by the hydraulics?