aboutime 9 #1 Posted October 5, 2014 I have a C/175. My rear hubs are always coming loose. Is there a secret or any trick that will help keep the hubs tight. I have tightened the sets screws but they always work loose. Share this post Link to post Share on other sites
Geno 1,929 #2 Posted October 5, 2014 I can't see from the pic but are the locking nuts also on the set screws? Share this post Link to post Share on other sites
stevasaurus 22,883 #3 Posted October 5, 2014 You can drill and tap 90 degrees from the set screw on the hub so you have 2 set screws holding the hub on. Check the set screw you have, it should be cupped inward if it is not worn. Type "loose hubs" in the search box...a lot of older threads concerning this subject come up. 1 Share this post Link to post Share on other sites
Hossenfeffa 49 #4 Posted October 5, 2014 Use two set screws 90 degrees apart with lock nuts. Put the hub on and tightin down the woodruff key set screw enough to leave a witness mark on the woodruff key. Remove the hub and grind a notch in the woodruff key where the witness mark lies. Reinstall the hubs, tighten the set screws and locknuts. Problem solved 3 Share this post Link to post Share on other sites
pacer 3,174 #5 Posted October 5, 2014 One of my two 175's had the same problem - and, well it should, the hubs were really loose with just sliding them on the axle. The axle and key way were seemingly in quite good condition, the hub apparently just being sloppy. Not wanting to spring for replacement hubs, I figured I didnt have much to lose by first trying the 90° set screw trick - well that didnt last long Not wanting to give up, I figured 2 set screws just couldnt put out enough force to stop the 'rocking' of the worn hub, so I added a third set screw - giving one each at 10, 2 and 6 o'clock positions. I now have some 3-4 hrs on this somewhat unorthodox 'fix' and by golly its holding! Thats way longer than the couple other tries at it To keep the new set screws from "dimpling" or "eyebrowing" the axle and causing future pulling of the hub even more difficult, I slip the hub on and run the screw down tight, back it off and remove the hub, this will point out the seating point (the "eyebrow") I then take my die grinder with a cut off disc and grind a slight flat spot where this is, the screw can then make a mark and not interfere with future removals. 2 Share this post Link to post Share on other sites
meadowfield 2,595 #6 Posted October 5, 2014 Use two set screws 90 degrees apart with lock nuts. Put the hub on and tightin down the woodruff key set screw enough to leave a witness mark on the woodruff key. Remove the hub and grind a notch in the woodruff key where the witness mark lies. Reinstall the hubs, tighten the set screws and locknuts. Problem solved Works every time :thumbs: Share this post Link to post Share on other sites
aboutime 9 #7 Posted October 5, 2014 Thanks Pacer, I will give that a try. Some of my other tractor do have several set screws on the hubs. Share this post Link to post Share on other sites
doc724 925 #8 Posted October 5, 2014 This subject comes up quite often. Everything folks have said here is fine. However, the real trick is to get brand new, hardened, cup point set screws and new woodruff keys. The key word is hardened. Go to a good hardware store. If you don't pay at least $1 per set screw, you are likely not getting the hardened ones. Also, invest in a 3/8, eight point socket so you can really put the torque to those square head set screws. New jam nuts would not hurt either. Your total investment is less the $3 per hub, not including the cost of the eight point socket 3 Share this post Link to post Share on other sites
gwest_ca-(File Mod) 11,107 #9 Posted October 6, 2014 From the 1978-79 B, C and D-Series service manual Just snug up the lock nut to lock the set screw in place. Any tighter tends to pull the set screw back out. Garry Share this post Link to post Share on other sites
aboutime 9 #10 Posted October 6, 2014 Thanks for all the help on this problem. I will get new harden set screws and lock nuts. And will add two more sets per hub and notch axle with die grinder. Thanks again. Share this post Link to post Share on other sites
sorekiwi 761 #11 Posted October 6, 2014 While all the above fixes often work, I will point out that if your hubs have been loose for a long time, it is possible for the bores of the hubs to be wallowed out, and even the ends of the axles to be worn. Enough slop between the hub and the axle, and you start asking an awful lot of two or 3 setscrews. 1 Share this post Link to post Share on other sites
Don1977 604 #12 Posted October 7, 2014 As said above new keys. If there is any play between the keys and the key ways it will move and wear the ends of the set screws. Share this post Link to post Share on other sites
pfrederi 17,910 #13 Posted October 8, 2014 If you drill and tap new holes for the set screws be careful and do not over tighten the lock nut. Factory had a flat spot in the hub casting, you will be drilling on a curved and tapered surface. if you over tighten the lock nut it doesn't pull evenly and you can snap off the set screw. Do not ask how I know this..... Share this post Link to post Share on other sites
pacer 3,174 #14 Posted October 8, 2014 As typical of many of the posts here on the forum, this loose hub problem has brought out many fine pointers, hints, suggestions, etc. Reading through them I thought I might expand on my previous post about adding a 3rd set screw ... I have the great good fortune to have a well tooled machine shop with a nice mill and lathe and I often fail to consider that many (maybe most?) horse owners dont have these machines and have to resort to much more basic tools. In adding a set screw without a mill, a drill press is second best method, with doing it by hand least desirable. Using a Mill I am able to have the hub securely mounted in a vise and find the exact center of the bore. I first use a 1" end mill to mill a 'flat' on the rounded surface (per pfred) before drilling the 5/16" hole prior to tapping, I start the tap with the drill chuck in the mill, removing the hub to the bench vise to finish the tapping by hand. As I mentioned, in doing this on two quite loose hubs was strictly a "what do I have to lose" type thing and am very aware it has a high risk of failure. I have to say that both axles and key slots were in very good condition, the axles measuring in right on the 1 1/8" mark. I did replace the woodfuf keys. And if this "fix" shows any sign of loosening, the hub will be replaced. Share this post Link to post Share on other sites
aboutime 9 #15 Posted October 19, 2014 Thanks for all the help. I finally got time to work on the hub. Anyway I drilled 3 holes and tap them I use 4 harden set screws and used a die grinder on the axle. Seems to be fixed. The reason one set screw Is at a angle is because the keyway is wore in the hub. 1 Share this post Link to post Share on other sites
Geno 1,929 #16 Posted October 20, 2014 Looks good to me, nice job. Share this post Link to post Share on other sites
meadowfield 2,595 #17 Posted October 20, 2014 Doesn't look like it will be coming loose anytime soon :D Share this post Link to post Share on other sites
gwest_ca-(File Mod) 11,107 #18 Posted October 20, 2014 I think the secret to keeping the hubs tight is to retorque the setscrews 2 or 3 times after a bit of use. It may take more times than that in some cases. I think one will know when they have settled in for good by rechecking the torque. Garry 1 Share this post Link to post Share on other sites
Geno 1,929 #19 Posted October 20, 2014 Good point Garry. Share this post Link to post Share on other sites
aboutime 9 #20 Posted October 21, 2014 I think the secret to keeping the hubs tight is to retorque the setscrews 2 or 3 times after a bit of use. It may take more times than that in some cases. I think one will know when they have settled in for good by rechecking the torque. Garry Thank for the tip. I will check them often. The old set screws were flat on the bottom. No wonder the hub got loose all the time. I still have to do the other side. Some off my other brands of GTs it took a act of God to get them off. Share this post Link to post Share on other sites
aboutime 9 #21 Posted October 24, 2014 I tried it out today. The wheels stayed put. Thanks for all the help. Share this post Link to post Share on other sites
Horse46 519 #22 Posted November 24, 2014 I have a question, why is there such a big gap between the hub and the housing.? Surely this would have the same effect as fitting spacers to a car hub to give it the wide wheel look, which can cause premature wear to bearing. Share this post Link to post Share on other sites
stevasaurus 22,883 #23 Posted November 24, 2014 Horse46...to answer your question...my opinion...the early horses (58/59 RJ's, Suburbans and most round hoods...the axles stick out enough to accept the hub with little or no space between the axle housing and the inside of the hub. In any case the hub should be mounted so it is flush with the end of the axle. When you get to the Commando's and such, the axle is longer, but the hubs are the same...this was done to make possible for wider tires (turf) and not hitting the fenders. I think that when you get to the "B" "C" & "D" series...those hubs become 5 hole and are a little deeper to get closer to the hub...but not always. Regardless, the length of the axles is to make possible the wider tires and not hitting the fenders. You may be correct, that the longer axle facilitates more stress on the inside and outside bearings...weather the hub is snug to the axle housing or has 1' or 2' of space. One thing...the early horses had 1" axles...the newer horses have axles that are 1 & 1/8". Just my 2 cents. Share this post Link to post Share on other sites
rustykan 140 #24 Posted April 14, 2015 This subject comes up quite often. Everything folks have said here is fine. However, the real trick is to get brand new, hardened, cup point set screws and new woodruff keys. The key word is hardened. Go to a good hardware store. If you don't pay at least $1 per set screw, you are likely not getting the hardened ones. Also, invest in a 3/8, eight point socket so you can really put the torque to those square head set screws. New jam nuts would not hurt either. Your total investment is less the $3 per hub, not including the cost of the eight point socket The eight point socket really makes a difference. Had to buy a set on Ebay. Glad I found this post. Thanks! Share this post Link to post Share on other sites
squonk 41,464 #25 Posted April 14, 2015 8 pt sockets can be gotten in a day from Napa and are good quality. Mcmaster-Carr will have hardened screws and keys as well as a good socket and deliver in 2 days. If I have a little wear in the key groove I use Loctite Bearing and sleeve retainer on the key. Share this post Link to post Share on other sites