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Tekin T8 dirt inside...

Have anyone had problems with dirt getting inside their Tekin T8 motor? I drove two paks(6S) in soft sand few day ago with my almost brand new T8 1550kv motor. Had lot's of fun with paddle tyres, but then the car went dead. I open'd the motor and almost got a shock... it was full of sand. The rotor kevlar wrap has got some damage and one magnet are missing a small piece from the rear end. Also the sensor board seems to got some sand blasting, the small components on the board has rounded edges now. Don't know if it works anymore..? Can be that the small piece of the rotor magnet also did a short cut on the stator and fried my Xerun 150A ESC!!! Havn't got it working since.

Seems that the sand has got inside the motor from the rear part, where the wire solder bridges goes in. Why doesn't it have any kind of seal there? No other motor that I have own, have had similar issues with dirt getting inside. I'm really disappointed with this motor, it cost me 150 euros shipped, and it lasted for max 10 packs. I didn't had a clue you need to open it up, clean and refurb it after every pack you drive.

Now I consider between buying a new rotor and sensor board, or do I throw it in the trash and buy a chinese Leopard 1600kv for less $$ and get lots of more reliability..?

Any thoughts?

I put small pieces of electrical tape on the inside holes of the front end bell (holes not being used). For the rear I used high density foam in between the rear cap and solder tabs. When you tighten down the rear cap the foam would squish between and form a seal. Kept A LOT of dirt out when I ran on loose/sandy tracks.

@ Maxximo Sand is one of those surfaces where you will never keep the material out of the anything. It's more a matter of managing how much and where it goes. The motor must have gotten a lot of sand in it to do that type of damage.

The motor can be sealed up with some clear silicone in both the open motor holes and rear solder tab areas. It's not done from the factory because this would hinder it's ease of tear down for maintenance.

Sand can and will destroy anything that moves, literally. Bearings will be worn out 10x faster than most any other surface. Running in sand requires 10x the maintenance simply because it gets into everything.

A new rotor and if required new sensor board should bring it right back to top performance. Chances are that if the esc failed it's because it wasn't able to sustain that load. Again sand is right up there with tall grass and water for sustained high loads. The esc likely failed due to this.

What car are you using? Battery? Gearing?

Like I say'd, I almost got a heart attack of the amount of sand inside the motor. I had tape on the extra fastening holes, the only way sand got in was the solder tab area. Didn't know it was open directly to the rotor area.

The car is an old modified Hyper 8/8,5 pro buggy, gearing 15/48T. Battery: 2x 3S in serial, A-Spec 4500mAh 65C. The motor wasn't too hot, could easily hold your hand on it. I doupt the load was too much, the car isn't that heavy. Maybe the motor resisted because of the sand and increased the load on the ESC..?

http://koti.mbnet.fi/pro-ht/RC/hobao...s_finished.jpg

can you post pictures of the T8 internal components?

Yes, I can. I will take some pics and post them up soon...

@Maxxim0 yeah that's definitely possible.

It appears as if something larger than sand made contact with the rotors edge.

Can it be that the rotor has had a crack in the magnet from the beginning? When I now look(in good light) at the area that missing the piece, it seems darker than the small hits on the magnet edges.

Anything is possible. However looking at this pic something very hard cycled through the motor at speed to leave that mark in the rotor.

Clearly there is other pitting,etc from the sand.

The kevlar wrap doesn't look bad at all so I'm still leaning on a rock or other material cycling through the motor and breaking the rotor.

The sensor board while pitted looks ok. You can test it with the sensor checker on your Rx8.

You may only need a new rotor.

Well, there was nothing more than quite fine sand and a "big" piece of the magnet, plus smaller magnet particles inside the motor.

Use silicone to seal the T8 from the outside, it works perfect for me since two years even in the wet

http://www.heberger-image.fr/data/im...4_IMGP9861.jpg

I applied silicone around the sensor wire, in the holes in the front of the motor and in the hole around the solder tabs

I see, I should have realized to take the motor apart when it first arrived to me... :(

you always learn from doing mistakes ;)