Bonsainoob88 Posted January 16, 2021 Share Posted January 16, 2021 Hello all, I have a arrma granite 3s blx. Basically brand new . After about 5-10 charges the car is unusable. The motor does not drive properly and after sending to seller for repair they sent it back to me apparently fixed . So we thought great , charged battery and took it out . After less than 30 seconds the same problem has occurred again After emailing Seller they said that there was a partially seized bearing in motor housing , maybe there was but I'm pretty sure that I checked every bearing before sending it in to get fixed . And if it was a partially seized bearing on original fix then why is it having the same issue now again with brand new bearings . At about 170 pound for a new esc and brushless motor I feel robbed and annoyed if I have to fork out for new parts after about 8 uses ! I can live with bearings , broken cogs and impact damage but not expensive electrical equipment that shouldn't be failing after a few uses I have attached a video of the problem and would like any advice as to how to check the esc / motor independently with a multi meter if possible. Or any known common faults with these parts that may shed some light on my issues Also attached image of parts in question Thanks guys I hope you can help VID-20210115-WA0008.mp4 Quote Link to comment Share on other sites More sharing options...
Tug Posted January 16, 2021 Share Posted January 16, 2021 Have you run it wet? If so, you need to administer proper after run care. Wiping down isn't enough. It's virtually a complete rebuild to remove all water from all bearings. 1 Quote Link to comment Share on other sites More sharing options...
Bajadre Posted January 16, 2021 Share Posted January 16, 2021 (edited) defo sounds like the motors on way out id just replace that part first before buying a esc /motor combo Bonsa is it still under warranty? send the motor into Arrma and let them send you a replacement if oossible. id desconnect the motor and see how it turns by hand should be a bit notchy as its brushless and the magnets are powerful any play them its defo bearings gone Edited January 16, 2021 by Bajadre Quote Link to comment Share on other sites More sharing options...
Tug Posted January 16, 2021 Share Posted January 16, 2021 Also, the way those motors cables are vibrating suggests large current draw. Check that the coloured connectors are tight. Quote Link to comment Share on other sites More sharing options...
Bonsainoob88 Posted January 16, 2021 Author Share Posted January 16, 2021 37 minutes ago, Bajadre said: defo sounds like the motors on way out id just replace that part first before buying a esc /motor combo Bonsa is it still under warranty? send the motor into Arrma and let them send you a replacement if oossible. id desconnect the motor and see how it turns by hand should be a bit notchy as its brushless and the magnets are powerful any play them its defo bearings gone Motor feels notchy with no play when I turn by hand. the rc car was bought December 2020. 1 Quote Link to comment Share on other sites More sharing options...
Bonsainoob88 Posted January 16, 2021 Author Share Posted January 16, 2021 41 minutes ago, Tug said: Have you run it wet? If so, you need to administer proper after run care. Wiping down isn't enough. It's virtually a complete rebuild to remove all water from all bearings. Yes it was run in the wet and it has been stripped more times than it's been together lol. In the video I posted there is only 2 bearings in the set up and they are brand new so the problem in video nothing to do with bearings . I do think theres a loose connection or something though , the only thing is I dont want to start stripping wires incase I void warranty Quote Link to comment Share on other sites More sharing options...
Nitroholic Posted January 16, 2021 Share Posted January 16, 2021 You sure your battery is OK? For a no-load motor run, that was pretty sluggish Quote Link to comment Share on other sites More sharing options...
Tug Posted January 16, 2021 Share Posted January 16, 2021 LVC is turned on? Quote Link to comment Share on other sites More sharing options...
Bonsainoob88 Posted January 16, 2021 Author Share Posted January 16, 2021 Battery was on 85% on video . Does anyone know what voltage I should have coming out each lead from esc when I pull full throttle ? That way I can make sure I'm getting correct voltage from esc. Also what resistance should I have across motor windings ? Cheers. Quote Link to comment Share on other sites More sharing options...
zlab Posted January 16, 2021 Share Posted January 16, 2021 (edited) It will be difficult to measure the output from the ESC, you would need 3 channels on an oscilloscope with insulated inputs. Measure the resistances between windings. All 3 measurements should be about the same. The easiest way is a cross check with another motor/ESC Edited January 16, 2021 by zlab Quote Link to comment Share on other sites More sharing options...
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