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This is advice, mainly on how not to do things and a couple questions..
I received the new (correct) wheel bearings yesterday. I had already taken the old races out of the wheel hubs and was prepared to install the new ones.
What I should have done was to take the new bearing races and wheel hubs to a machine shop and have them installed by someone with a press. Would have cost me probably about $20 dollars and took about an hour.
What I did do was to try to install them with a seal & bearing driver kit from Harbor freight. What I have now is a mess. The outer races went in fine, absolutely no problems. The inner races.. well... both went in crooked and in my impaitence and frustration, I made things worse. I actually cracked one of the races and the hub has a ridge from me trying to pound the race in.
So I'm now trying to determine the best way out of the mess I've created for myself. Can the ridge be machined out? If I do, will the bearing race seat properly in the hub or do I have to get a bearing with a slight large outer diameter? Or should I just buy new/used hubs?
-Matt
1993 Midnight Blue Porsche 968 Cabriolet (toy! Currently under restoration)
1995 Jeep Cherokee (war wagon, Zombie Apocalypse Response Vehicle)
2015 Mazda 3 (my reliable, nice car)
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Doubt that there is any reason to get new hubs; I've been around a lot of machinery rebuilds on equipment that was decades old. Usually just a good cleanup of the seating area is all that's required. It would help if you could give us a picture. I suspect you could just clean up the hub (it's OK if there is some material missing behind the race) and use as is. If the ridge is as I suspect, you should be able to use a carbide scraper and remove the material. If you are going to use a dremmel or the like, mask off all the area around the ridge, so a toughdown outside the ridge will do minimal damage. Do try to take out the minimum amount of material while assuring that the ridge is gone/slightly below the surrounding surfaces. Get us some pics as that might help.
Some bearings with through the race cooling/lube (mostly for very high speed applications) actually have a groove machined in the back of the race for the air/oil lube mist to be delivered to the bearing through a series of radial holes in the race. And, there are numerous other applications where there is less than 100% material backing up the race. So don't worry about removing the material at the ridge. It's not really needed for adequate performance of the bearing.
For future ref. a common assembly technique for fitting bearings is to either freeze a race so it will slide in easier, or if the tight fit is on the ID heat it up before assembly. And, take the mating part and either heat it in the oven for OD fits, or put it in the freezer for 24hrs for ID fits. This will usually give just enough change in dimension to the parts that the fitting will be a lot easier. And you don't need a press. although that would make it easier. Just use a brass rod/punch to tap in the race.
'92 Midnight Blue 968 Coupe
'94 ProbeGT, Eaton SC@9psi, Quaife, TecGT ECU, 300+HP, body sold, parting out
'98 3000GT VR-4, 400+HP AWD beast, didn't fit w/race helmet, Sold
'93 Bone Stock MX-6 Sold (in '05) sadly to the crusher in 2010
'61 Triumph TR-3, White with red leather interior; My First Car
(This post was last modified: 08-18-2012, 03:39 PM by
MB968.)
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I have hubs on the car again, that's a result. I worked the crooked new race out, but it was damaged in the process. I cleaned up the ridge in sealing area with a dremel, cleaned the hub, and installed the best looking of the old races in its place (taking my time). Probably not the best but should work for the short term. I used all the new bearings and their cages.
Thankfully these are the front bearings, Tama, so not that much of a problem..
I did heat the hubs prior to trying to seat the races yesterday, MB, but didn't freeze the races. I suppose I should have done that, but really, I blame this mess on my mental state. I wasn't in the mood to be wrenching yesterday.
-Matt
1993 Midnight Blue Porsche 968 Cabriolet (toy! Currently under restoration)
1995 Jeep Cherokee (war wagon, Zombie Apocalypse Response Vehicle)
2015 Mazda 3 (my reliable, nice car)
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After getting the rotors on and spinning the wheels, one is completely silent. The other makes a noise, kind of a click - click -click, that's definitely related to the speed. I verified tightness of the nut -- I can just barely move the washer with a screwdriver. Unfortunately I didn't mark which had the old race in it, but I'm guessing it's this one.
I suppose the noise means I get to do this again in the near future!
-Matt
1993 Midnight Blue Porsche 968 Cabriolet (toy! Currently under restoration)
1995 Jeep Cherokee (war wagon, Zombie Apocalypse Response Vehicle)
2015 Mazda 3 (my reliable, nice car)
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And car is mobile again. I took it for a testdrive and it feels nice and tight up front, no growling or noises that I could tell. Now I feel like its ready to go get inspected and Dr.P willing, legal to drive. I'm really looking forward to some serious cockpit time..
Thanks to all that have helped!
-Matt
1993 Midnight Blue Porsche 968 Cabriolet (toy! Currently under restoration)
1995 Jeep Cherokee (war wagon, Zombie Apocalypse Response Vehicle)
2015 Mazda 3 (my reliable, nice car)
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86' India red 951 3.0 8v turbo
87' Guards red 951 parts car(scrapped :-( )
93' GP white 968 manual, coupe(restoration/modifications in progress)
"I couldn't find the sports car of my dreams, so I built it myself."Ferdinand Porsche
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Yes! Excellent tutorial and what I followed (evidently badly) when doing mine. The same youtube user also has a nice tutorial on timing belt changes.
-Matt
1993 Midnight Blue Porsche 968 Cabriolet (toy! Currently under restoration)
1995 Jeep Cherokee (war wagon, Zombie Apocalypse Response Vehicle)
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Make sure the hub is warm/hot when reinstalling the races as well. If you're slow in getting the job done, you will do damage to the hub. I put the races in the freezer, but I don't know if it really makes any difference...
Joel Wahlsten
93 968 Amazon Green w/LSD and a few mods
2017 Cayenne GTS Mahogany Metallic
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I use the Valvoline synthetic grease and haven't had any issues.
I use Hawk HT-10s on the track and have Porterfield RS-4s for the street. Both work well. Low dust...not so much
Joel Wahlsten
93 968 Amazon Green w/LSD and a few mods
2017 Cayenne GTS Mahogany Metallic
(This post was last modified: 09-15-2013, 01:17 PM by
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I would HIGHLY advise from experience bringing the hubs/races somewhere that has a press (hell, bring them into a harbor freight store and use the floor model) rather than trying to put them in with a hammer and the press tools.
I can almost guarantee you will drive it in crooked with the stupid hammer tool no matter how much you heat up the hub. I ended up with a set of the press tools that did NOT fit the race sizes properly (Neiko Tools, from Amazon), and ended up with a broken tool before the hub went in. Then I got a set of the Astro Pneumatics ones from Amazon and they fit properly (just marginally smaller than the races, which is what you want). Took the set and hubs/bearing races to a local shop and pressed them in about 2 minutes.
1994 Slate Grey M030 Coupe