AE Racer

I'm having a very strange problem with my monster stock. It makes a screeching noise when you run it, and if you spin it by hand (only if you spin it pretty hard). I checked that it was shimmed correctly a bunch of times because I thought it was one of the shims scraping against one of the bushings. After having no success with shimming it differently, I took all the shims out to make sure that that was the problem. When run very slowly it runs normally, but once you apply any more throttle the arm shoots all the way down in the can and starts scraping on the bushing pretty hard making a screeching noise. What is causing this? When I broke in the brushes I didnt have this problem, although it wasn't getting much power so it probably wouldnt have happened anyway. It started when I put the motor in my car and gave it some throttle with the wheels off the ground just because I was curious to see how fast it spooled up compared to my 19T. When I did this the bushing in the endbell started coming loose I pushed it back in but I figured that the loose bushing was the problem. Now that I recall, the pinion would stick out farther when it made the noise, so the same thing was happening. I secured the bushing by putting a tiny bit of CA in the endbell where the bottom of the bushing rests (not the sides because that could cause misalignment) and then I put the bushing on the arm and tapped the motor together.

Any help would be appreciated

(I also put this in the stock motor forum but I need to run the motor tomorrow and Im not sure I will get a response soon enough, with it there.)

craziracer

maybe the magnet came loose?

AE Racer

Nope, the magnets are still glued in place.

kartermdb

iTrader: (15)

try some bushing oil on the bushings, if u let them go try they make lots of noise

AE Racer

I dont think they would make this much noise, and that doesnt account for the arm shooting down into the can. Its the arm scraping against the bushing with a good amount of force thats making the noise. I don't have any bushing oil, but I tried a little light bearing oil. I know its not the right stuff, but it should keep it from making noise for 10 seconds, if that was the problem...

AE Racer

It appears that I was wrong and you were right. I only put a drop or two of oil on each bushing before. I loaded them up with oil and now the arm doesnt shoot down and it doesnt make any noise. Its really strange that a bushing that isnt oiled enough would cause the arm to shoot down though. Ill buy some real bushing oil tomorrow.

jhigga15

I didn't read what every one else said...But I had this same problem with mine in a TB01 rally -- I fixed the problem by lubing the inside of the motor with white lightning...It has worked great ever since

Desolas

iTrader: (2)

Also polishing the arm shaft as well as the inside of the bushing will help. What may be happening is the friction is causing the arm to drill/walk down the bushing. You may have very fine debris or wear on either the shaft or the bushing, and that could cause this.

With as "un stock" as stock racing has become bearings should be allowed in the motors unless it's a spec race.