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AntiSplat mains bearing preload

I'm anxious to hear the reply as I just had this done. I was under the impression that we just followed Van's instructions when putting the wheel back on. On the RV-14 mains Van's states to,

"Rotate each Main Wheel and Tire Assembly while hand-tightening the corresponding axle nut until there is no side play in the wheel and the wheel rotates with little or no friction."
 
Reflex said:
I'm anxious to hear the reply as I just had this done. I was under the impression that we just followed Van's instructions when putting the wheel back on. On the RV-14 mains Van's states to,

"Rotate each Main Wheel and Tire Assembly while hand-tightening the corresponding axle nut until there is no side play in the wheel and the wheel rotates with little or no friction."
Click to expand...

thought he used sealed bearings. These are usually fully tightened, unlike the tapered roller bearings in the kit that are not

Suggest getting alans input, as I believe following the kit instructions is likely incorrect for his bearings.
 
Call out to Alan. Will post what he says.

Yes, they are sealed bearings like on the nose wheel. We both have been using the nose wheel bearings for years and are very happy with them. This is my first experience with the main bearing mod.
 
Preliad

They are not tapered bearings so vans instructions for preload will not work. Post what Allan says but it will likely be “snug”…
 
From the man himself:

Tighten the nut up about as tight as you can get it, by hand (without a wrench!), and back off to the next flat to get the cotter key in.
 
rocketman1988 said:
yes

Yes, there is a machined spacer in the middle.
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I didn't see a spacer in between the two bearings on the main gear for my -7. They were done about 3-4 months ago. Looked up the bearing number (Spinco CSA 206-20) and see it has some sort of a locking collar but actually looks like a flange is resting on the surface of the original wheel halves that they machine to fit the bearing. A very good idea but I certainly don't see a spacer inside. There are certainly two spacers that ride on the axle on the outside of the wheel, but not the inside so I can only assume it is the strength of the wheels themselves that hold the bearings in position. I'm trying to figure out how much pre-load I can put on the big axle nut so that the brake flange bolt can be snugged up to prevent the brakes/wheel fairing from wiggling back and forth. Recommendations?
 
mr.sun said:
I didn't see a spacer in between the two bearings on the main gear for my -7. They were done about 3-4 months ago. Looked up the bearing number (Spinco CSA 206-20) and see it has some sort of a locking collar but actually looks like a flange is resting on the surface of the original wheel halves that they machine to fit the bearing. A very good idea but I certainly don't see a spacer inside. There are certainly two spacers that ride on the axle on the outside of the wheel, but not the inside so I can only assume it is the strength of the wheels themselves that hold the bearings in position. I'm trying to figure out how much pre-load I can put on the big axle nut so that the brake flange bolt can be snugged up to prevent the brakes/wheel fairing from wiggling back and forth. Recommendations?
Click to expand...
To clarify, the nose wheel mod has the spacer. The mains do not have a spacer and instead, the bearings are stopped by a .030" step in the bore according to anti splat.

There should be zero preload on the ball bearings per anti-splat. I actually ordered some 1.5" shims from McMaster to take up any slop. They worked great.
 
ASA told me 25 ft lbs on the nose wheel bolt.
For the mains, snug them up, then back off to fit cotter pin. (As mentioned above).
Cheers
Stephen
 
Treekiwi said:
ASA told me 25 ft lbs on the nose wheel bolt.
For the mains, snug them up, then back off to fit cotter pin. (As mentioned above).
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That's what i did. I was surprised with 25 ft/lbs - that was quite a bit of torque for the front wheel bolt. The main wheels are not as tight due to alignment of the cotter pin hole, and I did not want to drill a new one. It's "sort of snug". My understanding that sealed bearings need to be fully tightened for the best service life.
 
ve0kog said:
That's what i did. I was surprised with 25 ft/lbs - that was quite a bit of torque for the front wheel bolt. The main wheels are not as tight due to alignment of the cotter pin hole, and I did not want to drill a new one. It's "sort of snug". My understanding that sealed bearings need to be fully tightened for the best service life.
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I’m not sure what “sort of snug” is or what you mean by “full tightened” but you want zero axial load on the in the Anti-Splat main gear ball bearings, snug the nut then back it off until the cotter pin fits, just like the Van’s standard tapered bearings. The Anti-Splat main wheel mod does not include a spacer between the bearings’ inner races.

The Anti-Splat nose wheel bearing mod is different, it has a spacer between the two bearings’ inner races so the axle bolt can be tightened without applying axial load to the bearings.
 
DanH said:
Sealed and non-tapered, so they have a precision length spacer trapped between the inner races?
Click to expand...
Spacer between bearings’ inner races…
  • Yes for the Anti-Splat nose wheel mod.
  • No for the Anti-Splat main wheel mod. Snug the nut then back it off until the cotter pin fits
 
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johnbright said:
I’m not sure what “sort of snug” is or what you mean by “full tightened” but you want zero axial load on the in the Anti-Splat main gear ball bearings, snug the nut then back it off until the cotter pin fits, just like the Van’s standard tapered bearings. The Anti-Splat main wheel mod does not include a spacer between the bearings’ inner races.

The Anti-Splat nose wheel bearing mod is different, it has a spacer between the two bearings’ inner races so the axle bolt can be tightened without applying axial load to the bearings.
Click to expand...
This doesn't sound right for a singular, not stacked, sealed, non-tapered roller bearing in a wheel; application. Yes, the inner race should be a slip fit because it is the non rotating side, but from all of my experience with these types of bearings in automotive wheel applications is that the nut on the inner race is tight not loose. doesn't have to be crazy tigh but allowing the inner race to rotate on the axle seems wrong in a wheel application supporting 1000's of pounds. obviously very different from a tapered roller bearing.

no dog in this fight, but suggest further research.
 
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lr172 said:
This doesn't sound right for a sealed, non-tapered roller bearing in a wheel; application. Yes, the inner race should be a slip fit because it is the non rotating side, but from all of my experience with these types of bearings in automotive wheel applications is that the nut on the inner race is tight not loose. doesn't have to be crazy tigh but allowing the inner race to rotate seems wrong in a wheel application supporting 1000's of pounds.

no dog in this fight, but suggest further research.
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Larry, the key thing in this instance is whether or not there is an inner spacer sleeve. When there is an inner spacer sleeve, you want to clamp down on the assembly, clamping the bearing inner races tight. This is the normal arrangement.
In the case of the ASA mains, the bearings are pressed into a pocket in the hub with no inner spacer sleeve. If you clamp down on the inner races, you are basically crushing the hub halves together. Don't want to do that. So a very light clamping load is all you can get. It is a bit of an unusual arrangement because if there were a lot of drag in the bearing itself, the inner race could turn on the axle, as you mentioned. But that is how it is.
 
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