Stripped the large black gear

[nitroman 88]

can someone please tell me why the large black gear stripped , how can i get this really tight,

 

[rak12]

That gear is your spur gear, likely causes of it stripping is improper gear mesh between it and the pinion gear (the gear coming of the clutch bell). To set the mesh properly, lightly loosen the motor mount screws and slide the two gears together. A piece of notebook paper should be able to fit in between gears when the gears are manually spun, any more than a piece of paper is too much gap. Also be sure the gears are spinning in the same plane and not at angles to each other.

 

[nitroman 88]

when you say put the paper in should there be any marks on the paper or should it just wind through the gears, i just finished breaking this motor and this happened, i took the spur gear apart and the bearing melted apart.

 

[rak12]

the paper should come out accordion shaped due to the gears shaping it.

 

[hotrodrob]

+1 on that also be sure to adjust your slipper properly,i run mine 1/4 turn from all the way tight

 

[nitroman 88]

someone else posted that is may be the clutch slipping, what would be the signs of that, the truck ran great during the break in process, when i opened it wide open this happened.it is also possible the bearing just let go

 

[HPI-Killer]

One thing that that noone has mentioned that MIGHT be the cause, is not using any loc-tite on your motor mounts, therefore coming loose from the engine vibrations and coming apart. Even if the engine rattles it a TAD bit out of mesh, with how fast that spur and clutchbell are spinnging it would insta-shred your spur.


Also, make sore you stay away from alloy spur gears, I know, metal is so much stronger than plastic BUT, if something fails, it will DESTROY your tranny internals. Sticking to plastic spurs is cheaper than alloy and the tranny price.

Hope this helps

(use blue loc-tite, NEVER EVER red)

 

[nitroman 88]

thanks i am heading to the hobby shop now, i think being a rookie this was a gear meshing issue, if the clutch was slipping i would hear it when the truck was moving correct

 

[Snook Man]

i took the spur gear apart and the bearing melted apart.

That slipper clutch/spur gear does not use a bearing. If there was a bearing in the center of the spur instead of the stock bushing and it came apart the spur would become off axis and strip in short time.