Waterproofing axles or welcome water inside?

[Derwood]

I thought I would ask this question differently than what I have found in the search. My next scratch project is a scale BRDM-1 and it is an amphibious 4x4 vehicle.
The 1:1 uses solid axles and leaf springs so pretty easy to source that. Since the axles will be run underwater almost every time, I am considering venting the axles and running bushings over bearings. Has anyone tried this approach? My thought was to have a way to flush the entire axle out with a blast of WD40 and allow it to vent. Appreciate any advice...

DH

 

[Gula]

What axles?
Bushings, sure, I would, anywhere the water would touch metal on metal.
I would at least try to fill where the ring and pinion area is with a marine grease, so no dirty water can chew those two up.
However, I wouldn't put a hole in the axles for water to pass thru.

You could fill the entire axle with marine grease, it would rotate very slow and put some drag on your drivetrain.

 

[89Industries]

You could install a zirc fitting and pump grease through like 1:1 vehicles used to have. They make some smaller ones and you need the proper size grease gun. They make some smaller ones I've seen used on bike components.

Lots of different viscosities of grease out there. A little thinner grease pumps through a little easier and may add less drag.

What we used to do on steel bike frames that had weld vents is spray some wd-40, etc in. Let it dry then use beeswax to seal up the holes to try to keep stuff out. But removable because there's always somewhere else on the frame that water got into so you'd have to periodically let it drain and wd-40 it again. But there weren't moving components (bushings, gears, etc) so just getting the water out kept the rust away since WD-40 is not a lubricant. Something like. Boeshield t-9 does the water displacement and lubricates but it's thin. Not sure it would suffice for ring and pinion lubrication. Good for bushings though.

 

[hnoroian]

Cool project! I think you are on the right track too make sure you pack the axle tubes them self also.

 

[ferp420]

just buy sealed bearings and grease them and the gears if water gets in its not the end of the world as long as your using it regularly they wont freeze up if they do pop them out soak them in wd40 for about 5 min as good as new more grease and away ya go
and just a side note a sized bearing isent much different than a bushing when in the mud and water the main reason i have seen to use bushins is when a rig is way overpowered and is exploding bearings every run bushings also ware out pretty quick so your always changing them anyway i think beaings end up being cheaper

 

[meatmonkey]

I have several trucks I play submarine with.

Drilling a small hole for a 3mm grub screw on the axle and transmission housings allows you to purge the water out at the end of the day with a conventional grease gun with a needle fitting.

This makes a bit of a mess, as grease seems to continually ooze out the bearing areas during use, but it does significantly extend service intervals.

Would reccomend for regularly submerged usage.