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?
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.
I understand the rear axle bearings can be a !$@#. ArnnWorx even has a tool for them, and they describe it thusly:
Quote:This tool is for removal and insertion of the rear axle bearings. We originally designed this as an alternative to the 944's bearing tool (which is very expensive). But since that time we've found this tool to work just as well on a variety of other P-cars.
If you talk to those Porsche owners who have tried this task (bearing replacement), you'll find they have tried torches, sledge hammers and even freezing the bearings in an attempt to lessen the nightmare. If this task is in your future, consider this tool before you break out the hammers.
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.
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!
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!
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.
Yes, nice tutorial. My car has those same calipers.
Keeping it square is the key! Once bearings are askew then you are in the mire ( watching my choice of words here). Because of the slight interference fit careful alignment is essential. Tap a bearing on no more than 1/8" and check. Tap the high point to level off. Tap another point then if you have been too heavy handed. Always use light force at this stage, we are not trying to engage the bearing on the shaft at this stage merely align. Once you are satisfied all is well then give a more weighted blow which should be evenly felt all around the bearing. The bearing should move relatively easily at this stage because of the small amount of engagement. If it doesn't check squareness again. Tap the high point once more. As engagement increases so will the force required to seat the bearing. Distribute forces evenly.
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...
Sure does. Every .0001 helps!
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
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.
The HF 12-ton press is only about $100 with a 20% off coupon, and it's useful in more situations than just pressing in these bearings. It's a glorified bottle jack in an H-frame, so there's not much that could go wrong with it. I've had mine for years and used it for all kinds of things, most recently I think it was pressing out those short stock wheel studs to put on my shiny new wheels.
Well the project has begun. All dissembled, except for the races which I will attempt to remove and replace tomorrow. If I am lucky, I may rest on Sunday.....
That spindle looks a bit gnarley! What ever is on it and the lighting make it look like rust.
Putting parts in the freezer just doesn't cut it. Its not cold enough to make a real difference plus by the time you start putting parts together (square) things warm up. It will not make a blind bit of difference. That's why liquid oxygen is used for this purpose. No don't go and have some delivered in a container, its very dangerous to work with! Keep it square and a press as suggested wouldn't hurt, But, all the force you can muster will not help if the parts are not square!