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Hot Axles/Drive Shaft - LNC 2.0

fquails

Newbie
Joined
Jun 4, 2021
Messages
7
Location
Davis
New to the Losi Night Crawler 2.0. I picked up a used one with the four wheel steering, and everything is wonderful. Except the rear axle (which is also a front axle with steering) gets VERY hot!!! Even the rear drive shaft gets hot! So I did my research, and lack of grease in the worm gear seems to be a common problem. Took it apart, greased it generously. But it still gets hot! I am thinking bad bearing? Or bad worm gear?

I have ordered the HD Worm Gear set, and a complete Losi Night Crawler bearing set (with two additional 6x12 bearings) from Jim's Bearings. While waiting for the parts to arrive, I thought I'd ask more experienced folks about what else can cause the axle overheating? Again, it is the rear axle WITH steering (so basically, a front axle).

Should I also change the worm gear in the front, if I upgrade the rear axle's worm gear? I read somewhere that installing the HD worm gear is basically equivalent to overdriving, and I don't want to overdrive the rear axle while keeping the front axle as-is. No good.

Thanks for any help/info you can share.
 
Those "HD" worms are exactly what your NC2.0 came with...no difference in ratios (21:1). The difference (OD) comes when matching them with the 25:1 gears from the OG LCC...gears that aren't even available anymore.

As for the heat, and as you've discovered, it's a common issue. Periodic greasing helps but, it's just one of the downfalls of worms. Instead of gear teeth meshing and "pushing" each other around, you're basically running a screw against a spur gear...it's ALL friction generating sliding forces.

Grease, grease, grease. Make sure you have good bearings, shim everything tight and centered (your new gears include shims I believe), and keep it maintained. If you can, find a grease with a high film strength.

Sent from my SM-S111DL using Tapatalk
 
Make sure you're not over tightening your wheel nuts. The losi threads are really short and some times in order to keep the nuts on they are screwed on so tight that it binds up the bearings. (Experience speaking here), I did it. "thumbsup"
Ernie
 
Those "HD" worms are exactly what your NC2.0 came with...no difference in ratios (21:1). The difference (OD) comes when matching them with the 25:1 gears from the OG LCC...gears that aren't even available anymore.

As for the heat, and as you've discovered, it's a common issue. Periodic greasing helps but, it's just one of the downfalls of worms. Instead of gear teeth meshing and "pushing" each other around, you're basically running a screw against a spur gear...it's ALL friction generating sliding forces.

Grease, grease, grease. Make sure you have good bearings, shim everything tight and centered (your new gears include shims I believe), and keep it maintained. If you can, find a grease with a high film strength.

Sent from my SM-S111DL using Tapatalk

Thanks for the info! The HD Worm gear set I bought includes two sets, so it’s good to know I can just replace the rear for now and save the other set as a backup. I am actually looking forward to replacing the worm gear as I enjoy working on my rigs almost more than driving them. And I’ll be sure to put good grease on it.
 
Make sure you're not over tightening your wheel nuts. The losi threads are really short and some times in order to keep the nuts on they are screwed on so tight that it binds up the bearings. (Experience speaking here), I did it. "thumbsup"
Ernie

I was hoping that was the solution, as that would be an easy fix. So I loosened my wheel nuts. But unfortunately, the rear axle still got hot while the front remained relatively cool. I have 15mm hex extensions for all four wheels, so I wonder if those have something to do with the rear axle overheating? But the front stays cool, so…Regardless, thanks for the tip, so I will make sure not to overtighten the wheel nuts, and just use loctite to keep them in place.

Looks like I’ll be installing new bearings and worm gear next week when the parts arrive. Hopefully those will fix the problem.
 
UPDATE: So I replaced the worm gear and all the bearings in the rear axle. There was still too much heat! Turns out all I needed to do was lube (dry lube) the driveshaft’s dogbone cup. Heat issues gone. Duh. Glad I kept the old worm gear and bearings as they are still apparently good because they didn’t cause the overheating issue. In case anyone is experiencing the same issue—lube the driveshaft dogbone cup first. If that doesn’t solve the problem, then check the worm gear and bearings.
 
Hudy Graphite grease mix with Hex Boron Nitride is a killer combo for killing the heat.
 
Any specifics on what Hex Boron Nitride works best, or how much to mix in to the tub of Hudy Grease?

I think it was 4% by weight if i remember correctly. Which is about the size of a couple aspirins. A little goes a long way with that grease

I just bought the Hex Boron off Amazon in a small tub. Not cheap! I also add it to Boeshield T-9 lubricant and is great for the driveline. Doesn't attract too much dust/dirt like a lot of the other lubes i've tried.

https://www.amazon.com/MICROLUBROL-HEXAGONAL-NITRIDE-Powder-micron/dp/B01N4CSJCB
 
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