Front wheel bearing adjustment, Scarebird kit on 1941 Oldsmobile original spindles This kit uses 1995 Chevy 1500 truck rotors and Scarebird says use A3 outer and A5 inner bearings. and was installed in 1990's. This car was put on the road by a deceased friend in early 90's. While going through front brakes I found some slightly rough bearings. The ID of new A3 bearing is .84, old bearings same # are .755, both have #M12649 on brg. It seems the bearing spec has changed in the last 30 years. If I do the usual snug the bearing then back until there is no torque on the spindle nut and very little play there is no hole for the cotter pin. If I loosen a wee bit more to put cotter pin in then there is excessive play when grabbing the rotor and wiggling up/down or left/ right. I found if I preload the Left almost has no play at 65 in lb and the Right at 55 in lb. Should I leave the preload or go with the sloppy fit by backing off to next hole ?
Senginc: You really don't need an inch pound torque wrench but try this technique on how to adjust wheel bearings: https://www.google.com/search?q=how...&ie=UTF-8#kpvalbx=_uh0mY62bFKiyqtsP7Ka02A4_24
Unfortunately this is when Olds and some others had left and right hand threads. The nuts won't swap.
I have been doing this for 50 + years and this is the first time I have had so much play when doing it the normal way. I used the torque wrench to know how tight it takes to get the play acceptable. If this had the stamped steel castle lock over the spindle nut (like many later cars) which has more adjusting positions would do it but I would have to grind a substantial amount of castle from the original spindle nuts to achieve this.
Well shucks...might be best to shim or remove some off the face of the nut/s to get them where they need to be. Wouldn't take much if they're near half a castle.
If you don't want to shim behind the nut, drive out a bearing race and shim behind it, the race will hold the shim tight and you don't have to worry about the small surface area of the nut holding tight to a shim. Brass shim stock is easy to cut and fit, and the larger surface area will be better.
I just looked on Scarebird website and they no longer have telephone support. I'll have to try their email support.
I may have to try this. I don't have a mill, all I can do is take a grinder or hand file and maybe get the surface level. I think the castle nuts use 1 1/6" socket, maybe there is stamped steel castle lock that fits something else to fit over the spindle nut. like this
I would be more concerned with the size issue. That is a lot of play between the spindle and bearing!
I've never "preloaded" a wheel bearing in the 59 years that I have been packing wheel bearings, I just do pretty well as you did at first, tighten the nut until I know that it is snug, back it off and then turn it until it just lightly snugs up so it is as my auto shop instructor said in 1963, "neither tight nor loose". I've done at least a thousand if not two that way and have never had one that had a good bearing when I packed it come back with a failed bearing. I have never washed a wheel bearing with solvent either as that is the other thing he taught us, Never wash a wheel bearing out with solvent unless you believe it is bad in the first place.
More on the size issue. I would measure the bearing sets OD/ID/width and check here: https://bearingfinder.ntnamericas.com/category/components-for-tapered-roller-bearings--inch-and-j for a better fit.
Bearing numbers and their corresponding dimensions have not changed. The ID of an M12649 is .8437", and always has been that size. If you've got a bearing with that number and a .755" bore then there's gotta be a sleeve in the bore of that bearing to reduce the diameter. The same as Mr 48 said, I've never seen tapered roller wheel bearings that called for a preload at assembly.
Right or wrong, I’ve always seated the bearing to maybe 20-25 ft/lbs, back off to the hole and put the pin in. This is for greased bearings. On my dads trucks with oil hubs, we set preload by how the tire turned and came to a stop. Seemed to work fine for us. And I cleaned every bit of old grease out in solvent, air dried them in the sun in the the warm days, heater in winter. Repack and run them. What I was taught was to never spin a dry bearing.
I think the belief is if there are particles of metal in the grease, you should replace the bearing. The way I do it, I wipe off as much grease as possible then clean the bearings using fresh solvent. I do the cleaning with the bearings in one of those black plastic drain pans, when I'm done I look to see if there are any metal fragments left behind, kind of like panning for gold.
No way will this stay tight or safe with the wrong diameter bearings or lack of spacer shims installed. The camber and toe-in will always be off, and possible tire wobble. In the bus garage, the only time we need to really torque the bearings is to be sure that any new race is seated in the hubs, then you back off and set like any other bearing, not to tight or to loose. Smaller hubs just take the weight of the wrench to tighten the nut, again, not tight nor loose, just snug.
I use the side of the abrasive wheel on the benchtop grinder to take a little at a time off the backside of the nut until the nut aligns with the spindle hole. Rotating the nut back and forth as you grind helps maintain flat and the right angle to the threads You may have to make a few runs at it taking a little at a time so you don't overshoot it good luck
I have found Mark at Scarebird to be very responsive to e-mails. He responded to all my questions when I bought the kit for my Buick. The spacers need to be installed the right way, and the lip seal fully seated. If running a washer behind the nut, a thinner one may be needed. The DAD kit for the Olds is about the same as the CRZ Buick kit.
BINGO ! All the play I was having was due to the excessive clearance of the inner race to the spindle. Well my 73 yr old eyes fooled me again. After inspecting with +4 glasses and a bright light, I found the old A3 bearing with the smaller ID had the sleeve portion of the bearing spacer they provide. I guess 150,000 miles with the slight wiggle that roller bearings have caused the split. I installed the old sleeves in the new bearings and put the keyed axle washer on first to prevent the bearing inner race from spinning on the spindle, then used the bearing spacer (minus the now separated sleeve) next to the spindle nut. Then I was able to preload 10 ft lbs, then loosen and tighten with hand and drop in next loosest cotter pin hole.
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