Knock Off hubcaps

[Dave Wharran]

My car uses true pin drive hubs on the front. The tapered roller bearings press directly into the pin drive hub. The spindle nut is located 3 inches or so inside the hub.

I had what sounded like a wheel bearing go bad the other day. How can that be with only 7500 miles on the car? It was a bad wheel bearing.
Well, it turns out that each time the car was washed and water was sprayed on the wheel, any that went inside the hub and made it through the outer bearing, would run into the larger cavity for the inside bearing and pool there. The inner bearing started to rust.

I considered covers, or hubcaps, for the hubs to be decorative in nature. They were on the list to do, but kept getting pushed back because of other projects.
It turns out that they are more than decorative. Running without them is no different than running any other car without the dust caps on the hubs.

A lesson learned.
A picture of a cap on a rear wheel.

 

[Tim Kay]

Dave, any suggestions on the related thread below:
Click here

Regarding the pic of your wheel, which side of the car are you picturing there and what direction is it heading. I'm curious to know because by the position of the safety wire I can tell which way the knock off turns to loosen. Assuming the wire is preventing the knock off from loosening.

 

[Dave Wharran]

Tim,
The picture is of the right side rear wheel. The right side hubs/knockoffs use left hand threads. The left side hubs/knowckoffs are right hand threads. As others noted in the thread you referenced, the knockoff nut tightens in the direction opposite of normal rotation of the wheel. If you were to hold the nut still and rotate the wheel in its normal forward rotation, the nut should screw on.

I safety wired mine.... The wheels are not taken on and off that much and it is cheap insurance against a nut coming loose. I had one that did just that several times until I wired it. Small teflon tubing keeps the wire from maring the wheel spoke/paint.

Dave

 

[Tim Kay]

When using saftey wire on BRM style rims, what is common practice - a small hole drilled through one of the spokes or simply wrap the wire around the whole spoke then attach through small hole on the spinner (as pictured above)?

 

[Tom_Hughes]

Hey Dave..

Who was the supplier for the caps?

 

[Dave Wharran]

Tom,
I made them on the lathe. They use an o-ring to hold themselves in the hub bores and seal againt water getting in. Works quite well.

Dave

 

[Steve Toner]

Won't an o-ring get destroyed by the heat generated by the brakes?

 

[Howard Jones]

The covers that came supplied with the trego (sp?) pin drive adapters that I have on my car look just like yours including the o-ring.

I don't think that there would ever be that much heat at that point unless you were maybe running several laps where the disks were getting red hot. I think the o-rings are safe.

If you are using a pin drive adapter like mine there would be no danger of water entering the bearing. REAL pindrives would be in danger of bearing dammage from water, brake dust, and bits of road junk.

 

[Steve Toner]

[ QUOTE ]
I don't think that there would ever be that much heat at that point unless you were maybe running several laps where the disks were getting red hot.

[/ QUOTE ]

Well that's pretty much what I was worried about. I was going to make some dust caps for my car since it didn't come from the factory with any, and the o-rings that I could find were nitrile, rated to 250 degrees F, and Viton, rated to 400 degrees F. I know the calipers on my Eagle Talon ran at well over 300 degrees on the track (measured with Thermax strips), but that's the calipers, and I don't know how much of that heat would transfer to where the o-rings make contact, and I wasn't sure I could get the Viton ones in the size I would need. So what I had planned to do was make the "neck" of the caps, if you will, slightly oversize (probably tapered out from the cap) and then slot it so it could be compressed and make a nice friction fit.

Here's a poorly rendered, exaggerated-scale drawing of what I had in mind: