Monday, April 14, 2008

Hubs and Bearings are not my friends.

While taking apart the front suspension, I kinda glossed over the disassembly of the all-important hubs, front brake rotors, and suspension uprights. In a sense, these do most of the work up front - they spin the wheels (hubs), stop the wheels from spinning (rotor/brakes), and steer the car (upright members.) This is all pretty important stuff, if you ask me, and so I was extra careful (and hesitant) when dealing this these.

I also did not know much about how these parts came apart, which added to my hesitation.

First, one needs to remove the dust cap at the center of the hub. One can remove this by using a metal chisel and a Big Freaking Hammer, and tapping the dust cover away from the hub. The dust cover has a lip that makes this fairly straightforward.

After removing the dust cover, one can see the actual stub axle around which the hubs and bearings spin. They bearings themselves are covered with a ton of axle grease, and are held in place by a castellated nut, which is held in place by a cotter pin.

At this point, the smart thing to do is to loosen and remove the two metal screws holding the brake rotor against the wheel hub. This is a royal pain! The screws tend to rust in place, and removing them requires a flat-head screwdriver. These tend to strip things more than anything. PB Blaster (my good friend) tends to help, but it's not a panacea for these things.

On the driver side, removing these screws required some effort, but they came out OK. I used the biggest screwdriver I could find, and I actually tapped them into the flat-head slot a few times before trying to break the screws loose. This worked the screwdriver into the screw head a bit, and helped in keeping the screwdriver from slipping all over.

On the passenger side, however, one of the screws refused to come out. After trying for about ten minutes, I just gave up for the time being.
(I hate flat head screws...)

Once done with this, one removes the castellated nut from the stub axle. This requires a few sheets of paper towels to remove as much of the axle grease as possible. Then you cut the cotter pin holding the nut in place, and you remove the nut. The nut itself is torqued to about 15-20 lb/in, so removing it is fairly straightforward.

Once this is done, you pull out the hub from the stub axle. That's it! The hub and brake rotor are removed, and you can do whatever you want with them. On the driver side, the rotor and hub separated as I pulled them (since I had removed the rotor screws.) On the passenger side, they came out as a single unit (and stayed together as a single unit, since that one freaking screw would not budge.)

After the hubs are out, one removes various brackets connected to the upright, as well as the brake rotor dust cover, and that's that. All of these parts were very dirty and somewhat rusty. Again, these parts would need some major cleaning and repainting before I put them back in the car. On the pictures above, one can see the hub right above the brake rotor. One also sees the outer bearing next to the brake rotor dust cover.

This is where the easy part ends, and the tricky stuff begins.

The hub unit itself houses two roller bearings (an inner bearing, and an outer bearing.) Each bearing is made up of three parts:
- an inner race ring, which sits around the stub axle,
- the roller bearings themselves
- an outer race ring, which is pressed inside the hub assembly.

At this point, one can do one of three things:
a) remove the bearings and inner race from the hub, while leaving the outer race rings pressed inside the hub; clean the bearings, re-pack them with grease, and replace them inside the hub
b) replace the bearings with new bearings; this requires removing the bearings, inner race rings, and outer race rings from the hub.
c) do nothing.

(A) sounds easy. And it is, for folks who have done this before. Unfortunately, I had never done this before.

The tricky part is that the inner bearings have a metal and rubber grease seal that must be removed in order to remove bearings themselves. This grease seal is pressed into the hub itself, and removing it is another one of those sounds-simple-until-you-try kind of things. Seriously. Most information on the web claimed this seal could be easily pried out with a screwdriver. Well, the WEB IS WRONG. I must be the dumbest guy in the world, but removing this seal was a royal pain in the ass. I had to buy a special prying tool, and use all the strength I had to remove the stupid thing. Grease seals are not my friends.

By the way, all that prying destroyed the grease seals. Make sure to order a new pair before you do any of this.

All that prying brought out a tiny spring that seemed to run along the inside of the inside bearing itself. At this point I thought I had ruined the inside bearing (since I could not tell where the spring came from.) Since I could not tell for sure, I figured I had to replace the bearing and play it safe.

Which brings us to option (B) from above. Which makes things worse; much worse.

You see, the bearings must be replaced as complete, matched set. Which means removing the outer race ring from inside the hub for both bearings. Again, the various online sources seemed to indicate this was a simple thing - just pry it out, and the thing just slips right off. Again, being the dumbest guy in the world, I could not pry this off. In actuality, it turns out, one needs to get a metal punch and a big freaking hammer and pound the outer race ring out of the hub - you "walk it out" by pounding around the circumference of the ring itself.

So I figured I'd give it a shot. After pounding for a few minutes, I realized the outer race ring had not budged in any perceptible way.

Stupid thing...

So, now I was faced with a potentially bent-out-of-shape inner bearing, a ruined grease seal, and a stripped screw that kept the right rotor and hub together, and no clue on how to proceed.

Desperation calls for desperate measures. And a bit of creativity. So, I brought the parts to Group 2 in Seattle (the local Alfa Romeo specialist shop), and begged for their help. As always, Joe English and the rest of the crew were very happy to help me out, answer questions, and all-in-all, allay all my fears and worries.

After chatting with them for about 10 minutes, we figured the bearings were OK to begin with. The mystery spring was actually part of the grease seal, which had to be replaced anyways. But after all this hassle, I figured I'd let the shop replace all the bearings with a fresh set. In all honesty, the bearings looked great, but considering I don't know how long these bearings have been around, replacing them seemed like a good idea.

The guys at Group 2 turned the thing around in an afternoon, and I ended up picking up everything a few days later. The shop installed and packed new bearings onto the hubs, and the pesky rotor screw was removed. Everything was A-OK again.

So, all in all, I have mixed feelings about this part of the repair. I think I could tackle removing the hub/rotor assembly from the stub axle, and I could probably repack the bearings if needed. But at the end, calling the experts saved me a lot of trouble and added frustration.

I think from now on, I'll stay away from hubs and bearings...

Saturday, April 5, 2008

Front, Pass Side Work

So, last time, I was removing the front driver side suspension. I had left the hub, brake rotor, and upright/axle section in one piece. I eventually took those apart; I'll describe that on my next post.

On this post, I'll chat about the passenger side.

I must say, there's not much to say.

Although I must start by saying that side of the car was nasty-dirty! On the picture you can get an idea for the layers of dirt, undercoating, and overspray resting on the whole suspension. Again, the idea is to clean and paint all this stuff up, and hopefully, make it look nice again.

Removing the passenger side suspension was basically the same as the driver side (duh...) This time around, though, I removed the hub and brake rotor from the upright/axle before undoing the rest of the suspension. (again, more on that in the next post.) I then removed the brake caliper, disconnected the steering tie rod, removed the suspension upright, then the lower a-arm, then the upper A-arm components. This all took about 2.5 hours - not bad for a rookie such as myself.

A few things of note:

-- Removing the upper camber arm (part of the upper a-arm) was a bit tricky, since it involves reaching underneath both carburetors to get access to the bolt to which the arm is attached. This was tricky - it required long socket extensions, as well as long breaker bars. I also had to remove the air filter, which requires disconnecting some of the engine vent hoses that connect to the filter housing. Once all the stuff was removed, access was still tricky, but eventually it did come out OK.

Having the radiator out of the way really helped. Again, I am not sure how to do this with the radiator in place (I am sure there is a way, though.)

-- Running my hand over the inside fender near the suspension pick-up points would remove all the fresh red paint, undercoating, and dirty. I could have filled up a 16-oz. cup with all the stuff that came out.
It seems that, when the car was painted recently, the suspension was not cleaned up much. So it seems the body paint got oversprayed over the dirt and undercoating, and hence, the paint has nothing solid to grab onto.
I am not sure what to do - I am almost tempted to scrape all the old stuff away, grab a few cans of paint, and spray the whole inner fender again. I am not sure I'd make things better, though.

So for now, the passenger side inner fender has two tones: parts with the newly-applied red paint, and parts with the original dark-red color. (I think it's Rosso Amaranto, but I'm not sure.)
(http://www.alfabb.com/bb/forums/car-restoration/3895-1972-alfa-romeo-color-chart-reference-materials-2.html#post33453)

I'll admit - I tend to favor the original darker red than the current red color. Maybe in a 20 years, when I re-restore the car, I'll go back to the original shade... Hmm...
(yea, right...)

-- I have not found any signs of rust in the body, inner fender, or anywhere else near the suspension. This is really good news.


Now I have a bunch of parts that need to be cleaned, re-painted, and re-installed. I'm still not halfway there...