Bearing squeal.

[GMack]

Was out trying out the new .700 firmware (went well) and upon a slow manual landing there was a loud ear-shattering squeal as the props spun down. P4 Std. is about 1.5 years old and no idea how much run-time off the two batteries (About 20 charges on each. My estimated flight time with them at 18 minutes may be about 12 hours in total.).

I suspect it was a bearing doing the squealing, but nothing different was felt or heard on spinning them by hand. I did notice a bit of looseness in one of the white nylon prop mounts on one motor so I tightened it up as well as the others.

Don't know if I can wick a bit of sewing machine oil into the motor through the air cutouts in the side using a very small CA glue nozzle, and maybe apply a bit through one screw hole in the the top for the upper bearing. Sewing machine oil is pretty capillary in action and can get into sealed bearings if the P4 has them. I've seen suggestions of using Tri-Flow oil via a pin-point oiler as well (Tri-Flow oil is available at local bicycle shops.).

Ideas?

 

[Newbieguy]

Both of my phantoms do it off and on. Unless you can see a prop spinning slower or when turned by hand you feel resistance I’ve been told by many to just ignore it. Take this advice as you will.

 

[WV. Rootman]

So there any benefit or harm to oiling the motors?

 

[MotorCycle-Man]

I think IF you would heat the lube points with a hair dryer "set on low and kept a nice distance away to warm the motors bearings.....you sure dont want to melt an plastic....the warmness sure would allow the lube to be sucked in the tiny small bearings much better ! a very tiny drop is all you need....keep us informed what you do OR dont do !

 

[Erised]

If you still have the older flat spring tabs(3) and they are more compressed than about 4mm the sound they cause is like bearing issues. Lift them up (bend) with your finger nail to reset to original height and this may stop the noise if they were compressed. I did this many times with my P4 before replacing them with the new coil spring type (it's worth the change). The bearings are sealed and if a lubrication issue is the problem oil will only be a temporary almost fix, once you start to oil you have to do it often as the bearings are originally lubricated with grease. If the bearings are going get a new motor instead of changing just the bearings as they are not expensive. I have about 8M feet over 400 flights on my P4 with no bearing issues, but I have had spring compression situations before I replaced with the coil springs.

 

[N017RW]

Oil will also retain dust and other fine debris, seep into shell, etc.

 

[GMack]

Hobby shop had some thicker oil for model RC cars. They call it more of a gear lube than an oil, about the viscosity of cooking oil.

I bought a really small nozzle for the CA glue at the hobby shop which looks as thin as a sewing pin. It is a taper fit onto the sewing machine oil can nozzle and was tight. The Pfaff Sewing Machine Oil is thin like water and it still takes a good squeeze to get a drop out of the tiny nozzle.

Before I began, I blew the motors out with compressed air and wiped them off. I put the oil into the side of the motor's air cutout and gave a drop there to the mid-section, or what I thought was a drop. There's three aluminum bosses for the arm-to-motor retaining screws from underneath so I snaked the tube in between them for that drop. Then I took out one screw of the white nylon prop holder and put a drop into there so it would run downwards and hopefully into the bearing. I marked the screw with a black Sharpie so I knew which one I put it into and if I did that motor too. I didn't see any signs of Loctite on those screws and left it off as I know it does crack plastic. I think the metric hex wrench was 1.5mm in size, but not sure. It had a long covered handle which went down to the tip and was design to correct the mirror cam for the auto-focus mirror inside the Nikon D800 series of DSLR cameras.

Afterwards, I spun them by hand and they do sound smoother. I'll spin them over the next few days and hope it wicks into the bearing if they are sealed. I'll let it wick around some more and maybe blow it with compressed air too.

Fwiw, the squeal sounded like a car's fan belt, not the rattle type of noise with a loose prop or flat or damaged ball bearing.

 

[MotorCycle-Man]

Hobby shop had some thicker oil for model RC cars. They call it more of a gear lube than an oil, about the viscosity of cooking oil.

I bought a really small nozzle for the CA glue at the hobby shop which looks as thin as a sewing pin. It is a taper fit onto the sewing machine oil can nozzle and was tight. The Pfaff Sewing Machine Oil is thin like water and it still takes a good squeeze to get a drop out of the tiny nozzle.

Before I began, I blew the motors out with compressed air and wiped them off. I put the oil into the side of the motor's air cutout and gave a drop there to the mid-section, or what I thought was a drop. There's three aluminum bosses for the arm-to-motor retaining screws from underneath so I snaked the tube in between them for that drop. Then I took out one screw of the white nylon prop holder and put a drop into there so it would run downwards and hopefully into the bearing. I marked the screw with a black Sharpie so I knew which one I put it into and if I did that motor too. I didn't see any signs of Loctite on those screws and left it off as I know it does crack plastic. I think the metric hex wrench was 1.5mm in size, but not sure. It had a long covered handle which went down to the tip and was design to correct the mirror cam for the auto-focus mirror inside the Nikon D800 series of DSLR cameras.

Afterwards, I spun them by hand and they do sound smoother. I'll spin them over the next few days and hope it wicks into the bearing if they are sealed. I'll let it wick around some more and maybe blow it with compressed air too.

Fwiw, the squeal sounded like a car's fan belt, not the rattle type of noise with a loose prop or flat or damaged ball bearing.

Keep that drone low for a while...keep it close....if a bearing squealed...its destroyed the bearings surfaces....Right now id sure be ordering a few new motors If i was you !.....Let US know what you decide to do...who knows that motor might have never had no lube !

 

[With The Birds]

Hobby shop had some thicker oil for model RC cars. They call it more of a gear lube than an oil, about the viscosity of cooking oil.

I bought a really small nozzle for the CA glue at the hobby shop which looks as thin as a sewing pin. It is a taper fit onto the sewing machine oil can nozzle and was tight. The Pfaff Sewing Machine Oil is thin like water and it still takes a good squeeze to get a drop out of the tiny nozzle.

Before I began, I blew the motors out with compressed air and wiped them off. I put the oil into the side of the motor's air cutout and gave a drop there to the mid-section, or what I thought was a drop. There's three aluminum bosses for the arm-to-motor retaining screws from underneath so I snaked the tube in between them for that drop. Then I took out one screw of the white nylon prop holder and put a drop into there so it would run downwards and hopefully into the bearing. I marked the screw with a black Sharpie so I knew which one I put it into and if I did that motor too. I didn't see any signs of Loctite on those screws and left it off as I know it does crack plastic. I think the metric hex wrench was 1.5mm in size, but not sure. It had a long covered handle which went down to the tip and was design to correct the mirror cam for the auto-focus mirror inside the Nikon D800 series of DSLR cameras.

Afterwards, I spun them by hand and they do sound smoother. I'll spin them over the next few days and hope it wicks into the bearing if they are sealed. I'll let it wick around some more and maybe blow it with compressed air too.

Fwiw, the squeal sounded like a car's fan belt, not the rattle type of noise with a loose prop or flat or damaged ball bearing.

It’s been a while since I have heard a fan belt slip, ribbed serpentine accessory belts seeming to be the norm- hear a good number of fragged idler pulley bearings though. No matter how ingenious the method of getting it in there or what sort of goop or high tech slippery stuff you use any reprieve from the noise is short lived. By the time you hear the noise the damage is done. Same deal for the little ball races in your motors.

What is strange in this instance is crook bearings will almost always reveal themselves by end float, runout, binding or roughness. You may find your looking for something other than a dodgy bearing.

 

[MotorCycle-Man]

It’s been a while since I have heard a fan belt slip, ribbed serpentine accessory belts seeming to be the norm- hear a good number of fragged idler pulley bearings though. No matter how ingenious the method of getting it in there or what sort of goop or high tech slippery stuff you use any reprieve from the noise is short lived. By the time you hear the noise the damage is done. Same deal for the little ball races in your motors.

What is strange in this instance is crook bearings will almost always reveal themselves by end float, runout, binding or roughness. You may find your looking for something other than a dodgy bearing.

Yepp......like i said above ^^^ when you hear that noise the smoothness of the bearing race is destroyed he needs new motors !....you have no other things or parts that could or would squeal like you described above ect moving parts ! Be careful around them fast powered Up blades please !

 

[RémyHeli]

Sealed bearings are not meant to be greased or oiled ´as is' but flange can be removed to open (quite difficult and can be damaged). Then clean, inspect inner race, no rusted ball, add little bearing grease and close. But bearings are cheap so better getting new ones. Too late if started to make noise..

With adding oil, the axis into the hole of the bearing can start to slip and wear instead turning with the bearing, leading to more problems. General observation.

Also it is not recommanded to mix lubricants. Adding oil can temp hidden problem and create more mess in the end.

 

[RémyHeli]

Find jet turbine engine bearing inspection (not my video)

 

[With The Birds]

Sealed bearings are not meant to be greased or oiled ´as is' but flange can be removed to open (quite difficult and can be damaged). Then clean, inspect inner race, no rusted ball, add little bearing grease and close. But bearings are cheap so better getting new ones. Too late if started to make noise..

With adding oil, the axis into the hole of the bearing can start to slip and wear instead turning with the bearing, leading to more problems. General observation.

Also it is not recommanded to mix lubricants. Adding oil can temp hidden problem and create more mess in the end.

Yes- squeeling is usually shaft spinning in inner race of locked bearing. Given the low hours on the AC in the absence of a crash it would seem it was a dodgy bearing at the time of installation. It should have revealed itself in manual manipulation of the motor bell though.

 

[MotorCycle-Man]

Just order a few new motors install...."Problem Solved" ! period .