I have a banjo rear end in my roadster. Well, since I have finally got it running and riving, it seems every time I take it out the left rear hub nut starts to back off. I have a pin in there and it stops it from completely coming off, but I noticed that the nut doesn't match the one on the right side of the car. It has a groove cut in the top of it and the one on the left that backs out doesn't. Help. What's a hotrodder to do? I guess I need another 'correct' hub nut, but will that stop it from backing off? Anyone have one that I could get from them real soon? r
Buy a new pair of nuts and torque them correctly and install new cotter keys. Be sure you have the B-1183 hub gasket installed in the recess in the hub snout too. You may need an axle shim or two!
Also check to make sure your hub threads are not stripped. Although they may look good initially upon close inspection they may be rounded or stretched.
Petejoe has probably identified the problem. If your axle nut keeps on loosening up the threads on the axle shaft or on the nut are in poor condition. The axle nut on a flathead rear axle should be torqued to minumum 200 lb/ft which is quite a lot and at that rating usually don't back off. Check the threads on both, If the threads are poor on the nut that is an easy fix. If they are bad on the axle that is a little more work that may involve rethreading or an axle replacement. .
Mac's Antique Auto Parts, Sacramento Vintage Ford, etc. should all have the parts. Also, Roy Nacewicz (sp ?) has pretty much all of the stock hardware pieces. Like was said before, check to make sure the threads are good. They are very fine and nuts are easily (and often) crossthreaded. The 200+ ft/lb torque figure is important too. Just cranking it on with a ratchet or breaker bar is not enough. 200 ft/lb is more than you think.
Your nuts can be found here at Macs Antique Ford Parts. Have you verified your axle shaft threads are good?
I haven't verified anything yet. I will as soon as I get home tonight. Thanks for all the good info. It really helps in this crunch. r
What about the shimming of the drum? Isn't it very important for the hubdrum to be pressed on the tapered axle by the 200ft/lbs of torque? So if the nut does come off, the drum is still tightly pressed on the axle.
Good point. These axles arent like the standard axles whereas you tighten as tight as possible by hand and then back it off some until the hub turns freely. These get torqued big time and only back it off to align the next cotter hole.
You need to check the axle key and if bad replace it. If you shear the key and spin the hub on the left the nut can tighten the hub so tight you will have to heat to a cherry red to remove. The nut sometimes shears the cotter key and the nuts pins with the hub and gets tighter than a bull's ass in fly time. Ask me how I know.
"What about the shimming of the drum?" I didn't see any mention of shims in the query...if axle is shimmed, that may well be a source of the problem. Shims just don't work well in this high stress application...shim can walk, complress, and even wad up into little rags of tortured metal in there, ruining the surface and loosening drum. If shims are needed, unfortunately you need to replace axle or something or take a more elaborate approach to getting the clearance shim provides. You must have a fit in which hub practically merges with axle, and it just can't do that over a shim, IMHO.
What about shims behind the hub nut? I torqued the nuts (got a new one for the driver's side) with a 150 ft lb. torque wrench, then stood on the rachet with all my weight and then jumped up and down on it to get it tighter. I still get some drum wobble and the driver's side drum seem a little 'loose'. r
I usually just use an impact to install those nuts. I havent screwed any up yet. Any wobble will screw up your bearings big time.
I still get some drum wobble and the driver's side drum seem a little 'loose'. r Something's going on...pullitapart, check drum to axle fit by hand and see if it wobbles when pushed on firmly. It may have been run loose or shimmed and have wear to the taper... If that is tight, run on nut without washer and fiber ring and check clearnaces to see if it is indeed not capable of tightening--if so, that's odd and maybe disturbing, but an extra washer or two would not be an unsound repair as long as you use decent automotive washers and not Home Depot grade, which are likely soft enough to wallow out.
Based on the last two responses... 1. Would replacing the bearings help? 2. I don't remember a 'fiber ring' behind the hub nut/washer. Would that be a problem? r
Fiber ring is just a final gasket to keep grease in hub--irrelevant to play, but you need it... Bearings, no, different issue...here, you need to determine if axle is perfect fit into taper of hub. Fit by hand, if wobble examine VERY closley, perhaos drag a file sideways over axle, not rmoving metal but exploring for burs and high spots. If baf fit isn't just a specific bur or something, hub may have been run loose on axle, serious problem. One or both would likely have to be replaced. Test dubious parts against good matching parts from other side...
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