Big Rock V3 big rock engine seized.

[Anthony80]

I've had the v3 big rock for a week or less and already have a locked up motor. It has minimal run time amd I don't believe it has ever gotten too hot. It started breaking hard on it's own then just locked up. I got arrma tech working on sending me a new motor, but even if they do, I'm concerned about this happening again. Im looking for any input or experience with this happening?

 

[L3phturn]

When you have been checking temperatures, what are you seeing?

What pinion are you running? What surface are you running on? Is everything stock?

 

[jondilly1974]

I've had the v3 big rock for a week or less and already have a locked up motor. It has minimal run time amd I don't believe it has ever gotten too hot. It started breaking hard on it's own then just locked up. I got arrma tech working on sending me a new motor, but even if they do, I'm concerned about this happening again. Im looking for any input or experience with this happening?

I would check the motor bearings. Did it get wet or in fine dirt or sand?

 

[Anthony80]

Everything Is stock. I am not sure what motor temps was as I was checking numerous cars that day, maybe around 107f or so. I was running on a very fine dusty outdoor track. I took the end cap off the motor and I didnt see any dust in there. I have yet to inspect the entire motor as I was waiting to see what arrma wanted to do about replacing the it before they had me send it to them with obvious Mark's where I would have taken it all apart and possibly ruin the warranty.

 

[Yas]

My bet is the pinion side bearing has seized from dirt ingress - very common problem with the 3s cars

With your next motor, I would try either sealing the power module with tape or sealant, or use an o-ring against the motor can like I did. I've been running mine like this since this post and it's held up perfectly, even on dirt tracks

https://www.arrmaforum.com/threads/blx-motor.20999/post-298602

 

[jondilly1974]

Everything Is stock. I am not sure what motor temps was as I was checking numerous cars that day, maybe around 107f or so. I was running on a very fine dusty outdoor track. I took the end cap off the motor and I didnt see any dust in there. I have yet to inspect the entire motor as I was waiting to see what arrma wanted to do about replacing the it before they had me send it to them with obvious Mark's where I would have taken it all apart and possibly ruin the warranty.

Yep fine dirt inside the power module is a bearing killer. Almost assured that is what did it. The motor bearings don’t have rubber seals so fine dirt sneaks right in.

 

[Outcastblxnut]

Not the new spektrum motor too??‍?

 

[Yonic]

Not the new spektrum motor too??‍?

It never was a motor problem. Its the hole in the bottom of the spur that is the problem. I just cant believe they they didnt find it important enough to fix this, i thought that the warranty costs will change their priorities about this, guess i was wrong.

 

[Arrmature]

It'll be interesting to see how the V3 motors hold up. It looks like the motor and servo are the two areas where they cut costs.

 

[Outcastblxnut]

My problem was motor bearings in the blx

 

[DoNoHarm]

It never was a motor problem. Its the hole in the bottom of the spur that is the problem. I just cant believe they they didnt find it important enough to fix this, i thought that the warranty costs will change their priorities about this, guess i was wrong.

Holes below the spur are a staple in chassis design to let stuff escape. Although in plastic chassis normally they just fence off the gears instead of leaving them open and having a cutout.

 

[Yonic]

Holes below the spur are a staple in chassis design to let stuff escape. Although in plastic chassis normally they just fence off the gears instead of leaving them open and having a cutout.

We’re taking about the 3s cars, they don’t have a hole below the spur, it has a hole in the power module, but the chassis is blocking the way for anything to escape. It let sand in and just grinds it until the sand is fine enough so it can enter the bearing in the motor and destroy it.

it’s the bearing that will go toast, but the reason is the hole in the power module.

 

[DoNoHarm]

We’re taking about the 3s cars, they don’t have a hole below the spur, it has a hole in the power module, but the chassis is blocking the way for anything to escape. It let sand in and just grinds it until the sand is fine enough so it can enter the bearing in the motor and destroy it.

it’s the bearing that will go toast, but the reason is the hole in the power module.

What’s a power module? Sorry I just really don’t know the term.

 

[Anthony80]

My bet is the pinion side bearing has seized from dirt ingress - very common problem with the 3s cars

With your next motor, I would try either sealing the power module with tape or sealant, or use an o-ring against the motor can like I did. I've been running mine like this since this post and it's held up perfectly, even on dirt tracks

https://www.arrmaforum.com/threads/blx-motor.20999/post-298602

Thanks for the info. I will definitely try the o ring mod. The track I run at is filthy with fine dust so I will need to do something to prevent this in the future. It's a shame, I was having a lot of fun with this truck. I normally run other brands and this was my first arrma, but dang I like it so far. I just hope I get the new motor soon. First thing I'll do is seal it up and them take it back out. Other than thicker shock oil, or maybe new shocks, it's a great basher so far.

 

[bicketybam]

What’s a power module? Sorry I just really don’t know the term.

30 years in the hobby and you don't know? ?

 

[parcou]

Yep fine dirt inside the power module is a bearing killer. Almost assured that is what did it. The motor bearings don’t have rubber seals so fine dirt sneaks right in.

I learn something new here daily.... I did read about cutting a hole in the bottom of the chassis few days ago and I did that for BR and Granite for that gear. So are you saying the link @Yas posted something I need to consider? I need to read the link to that full thread to get a good newbie understanding of what and process

 

[jondilly1974]

I learn something new here daily.... I did read about cutting a hole in the bottom of the chassis few days ago and I did that for BR and Granite for that gear. So are you saying the link @Yas posted something I need to consider? I need to read the link to that full thread to get a good newbie understanding of what and process

View attachment 101915

I am unsure which way is more effective. Sealing it out or letting it escape. Both could be effective in my mind. Letting it out seems easier. Sealing it out seems like an uphill battle. ??‍

 

[GRC]

This works. There is ZERO outside debris in my power module. I only have fine dust from the pinion/spur gear gradually wearing down. To prevent that from getting into the motor I use Yas' o-ring tip.
https://www.arrmaforum.com/threads/help-me-upgrade-my-senton-3s-for-sand.20322/page-2#post-297587

 

[Anthony80]

Still haven't heard anything about getting my new motor. I'm not sure if they will send a email saying they sent me a new one or what. I guess I could just swap in another motor if they don't get back to me soon. I hate dealing with companies directly, it's always a hassle.