refurbing the rear end...part two

OK, so the axles are ready and waiting to have their new bearings pressed on, and it's onto the housing. With the third member yet to be removed, the axle housing was heavy and awkward to maneuver. I made a few of chocks out of a scrap piece of 4'x4', and set about getting the third member ("pumpkin") out. This was tough. Following the advice of Chuck from BAMA, I started off by whacking the carrier with a dead blow hammer...this didn't get me very far, it must be said. I couldn't really use the Olshove technique, because I don't have an engine hoist....so I tried the razor blade method. Essentially this consists of poking at the very edge of the carrier gasket with a razor blade while being very careful not to damage the mating surfaces...and then whacking some more with the dead blow hammer...and repeating...ad nauseam...while thinking about going out to by an engine hoist!

 

Eventually I got it apart, but it was still very difficult to remove the differential case. I ended up using a bunch of wooden wedges I made for a previous project to force the case apart from the housing. With a lot of wiggling, and even more mess, I eventually got it out. I'm not sure yet if I will be changing the differential, and keeping the case, or just buying a rebuilt third member. Oddly, the latter may turn out to be more cost effective unless I do the conversion myself...and that's not really an option.

The edge of the housing was a bit messy, but otherwise it was in great shape with no serious rust issues. The gear oil was a thick black gunk, and stank out the garage.

After tipping most of the oil out, I leaned the housing in the corner of the garage. You can't see it in the picture, but the bottom is standing inside a plastic coke bottle with the neck cut off. I left it overnight to drain out as much of the oil as possible.

The oil seals looked like they were in good shape, but they cost like eight dollars each so it makes sense to replace them now.

Here's the view after I pulled the seal with a slide hammer.

I had to destroy the seals to get them out - I mean I was never thinking they were going back, but I was surprised how much they got bent up.

After wiping up a bit more oil that was hiding behind the seals, I got the wire wheel back out and gave the outside of the housing a good going over. I was expecting this to be tedious, but it was so much easier than working on my back under the car that I actually enjoyed it! The housing came out great. I removed the old gaskets from the end of the housing with a sharp razor blade and some 400 grit wet 'n' dry and they polished up nice.

The mating surface also needed a little bit of massaging - several segments were scratched, probably by me I'm sad to say, but they all smoothed out OK with some very fine sand paper. I then washed down the entire housing with a warm solution of Marine Clean, and wiped down with shop towels.

After drying, I gave the housing a coat of Metal Prep, which I left on for about 10 minutes or so, and then washed off with cold water. I dried the housing again first with a shop towel and then with compressed air until it was very dry.

After an hour of extended drying time (I think they call it lunchtime in most places), I busted out the POR-15. I've been waiting to try this rust treatment/paint for ages, as I've heard so many conflicting stories about results. I actually ordered a quart of POR-15 direct from the manufacturer back in...like...April. I must have been feeling ambitious at the time. When I got it, the can was dented, and had dried black paint on the outside of the can and on the inner packaging....but the lid was on tight, and there was no mess around the lid. When I opened the can it was about 80% full. Thing is, the lid was sealed on so tight and clean, that it must have been shipped that way.

Now, I should have returned the POR-15, no question. But years of shopping on the internet have taught me nothing if not that returning faulty goods is a total pain and costs more money (return shipping) and time (waiting on the 'phone) than it's worth. You know, you call up, and you get in the call queue for returns....and you wait...and wait...and then you get some idiot in, like, India or somewhere, and then they tell you to contact the carrier....etc etc.....blah blah....I don't know if POR-15 are like this, as I never called them, but years of similar experiences have worn me down to the point where I don't even bother to try to return stuff anymore unless it cost over 100 dollars...I just don't have time. So the POR-15 went up on the shelf....

...and now, six months later I'm ready to give it a try on my axle housing. If you've not used POR-15 before, it is extremely sensitive to water. This means that if you get a drop of sweat in your can of paint, you may as well toss it - it's never going to stick or cure correctly. Even the water vapor that makes up 1% of the air is important: leave the POR-15 exposed too long and it will start to become more viscous. The manufacture recommends you remove only the amount you need from the can, and reseal immediately - in other words, don't paint straight from the can. I chose to observe and ignore this recommendation at the same time: I poured most of the paint into a new metal paint can - I get them at Kelly Moore for a few cents - and sealed it up. I left what I needed in the original beat up can and used a narrow foam brush to spread it on the housing.

The POR-15 is self leveling, so there were hardly any "brush" strokes visible within a few minutes of applying the first coat. I gave it about three hours - the surface was touch dry by this time - and then foam brushed on a second coat. I then left the housing overnight to cure. Next day, well it looked OK. There is a speckly nature to the finish, like lots of tiny bubbles were in the paint (which there weren't as far as I could tell). It's not really good enough for anything that is going to show, but for the axle housing it is very adequate. The final look has a bright gloss; I know everyone seems to be into satin or flat black these days, but I actually like this look for the housing and brake backing plates, so I'm quite happy. I just need to snag a seal driver kit from somewhere, and then the housing can go on the "done" pile. Guess I'll find out in time if POR-15 does peel off....?

refurbing the rear end...part one

I'd like to say that before I set out on my project of restoring and upgrading the '68 I carefully planned out exactly what it was going to entail in terms of new items and replacement parts.....unfortunately the reality is somewhat different, as at the time I didn't even know the difference between four and five lug wheels. Oh dear. Eventually, after much research and input from the guys in BAMA my shopping list included an improved suspension, bigger rear axle, new front end, 5-lug wheels, better steering, front disc brake conversion, cable clutch and...and..and - well the list is still growing, and from what I see in BAMA, it probably never really ends. Oh, and I didn't even mention the new motor or transmission yet....this could get expensive...!

In my view the best way to approach a project of this size is to branch out and work on several things at once....so, while I've been working on restoring the underside of the car, I've also been hard at work researching rear end specs and shopping for a suitable candidate to refurbish. I got a lot of help from Kevinstang's page, this Mustang Plus shop talk article and woodyg's datalist.

The rear end I settled on came out of a '68 Cougar - it is exactly the same as the rear end installed on the V8 mustangs: it measures 54.25 inches inside the backing plates and the ring gear is eight inch, with a ratio of 3.00 :1. It also came with complete drum brakes which I will be rebuilding later - I'm sticking with drums in the rear of the car and doing the disc conversion upfront. I'm not planning to race the car, so I don't really need a nine inch ring gear, but I do need a lower gear ratio - right now I'm trying to decide between 3.55:1 and 3.80:1, either of which will work with a T5 or TKO transmission. I want the car to have some zip off the line, but I also need to be able to drive on the freeway...another compromise will have to be made here eventually. I also need to upgrade to a limited slip/posi differential at the same time or I'll be laying down stripe instead of stripes!

Dis-assembly started with the brake breather tube and the hard brake lines. The breather tube setup is actually quite new and I hope to reuse it. I will be replacing all the brake lines. There are four bolts essentially holding the brake backing plate to the carrier which are removed through the hole in the axle flange. Once these are out the brake assembly is loose like in the picture below:

At this point the axles can be slid out....in fact the shorter driver side axle did exactly that: it slid out without a second of fuss. Of course the passenger side was much tougher...oh yeah, it was stuck BIG time. Stuck way too hard for my crappy slide hammer to cope with. I wasn't sure what to try next, but fortunately the internet came to the rescue. A few minutes Googleing (is that a real word yet?) led me to this video clip and the "brake drum method". The crux of the deal is to reattach the brake drum the wrong way round. Use just a couple of lug nuts done up two or three turns each. The drum provides enough force, when it is crashed against the lug nuts, that the axle is easily pulled out. One of those things which may look too easy to be true but really works. The axles were in quite good shape, with just a little rust on the studs and on the flanges.

At this stage I took the axles into S+P Auto in San Leandro to get the bearings pressed off. It isn't the closest machine shop to my house by any means, but I happen to know the manager. Generally I put off visits there until I have another reason to be in the neighborhood. I've heard a horror story about machine shops charging 100 dollars for what is really only five minutes work, so I called ahead to ask, and was told 20 bucks each - and this was without mentioning my buddy. The guy I talked to also said he would turn them around straightaway. Even better, when I showed up he said it was 20 dollars to remove and replace the bearing, and as I was only having the removal done at this stage....he'd charge me half price! Sweet. And I still didn't need to mention my friend. So for 20 bucks and a five minute wait time, this was the result:

The axle is an awkward object to work on, so I built a jig to hold it from a spare Ikea shelf I had in the garage. I say built...I really just clamped the shelf to the bench and cut a hole with my jigsaw in the portion overhanging the bench:

The axle slotted right in and was easy to work on with my wire wheel. Here's the "before" picture:

After cleaning with a wire wheel and a fine sanding drum on the Dremel it looked like this:

I taped off the the ends of the axle shafts, first with masking tape, and then covered that with a thick layer of duct tape: the idea is to deflect any stray swipes from the wire wheel without getting the shaft covered in the gunge from the duct tape. This worked well and both axles came out good:

After cleaning, prepping the metal and neutralizing, the axles took on a dull hue.

I actually made a miniature booth in my shop to paint the axles and some other parts (more on than later). I also converted the shelf into a drying rack by making two more bores with a holesaw. Then I hit the axles with two thin coats of Eastwood brake gray and left them to cure. Next I'll be working on the backing plates and other parts before I take the axles back to S+P Auto to get their new bearings pressed on.

Castro Valley Fall Fest 2010

With my own car on sabbatical from the show circuit for the foreseeable future, I've been going to shows either as a punter (Redwood Chapel, Ponies and Snakes), or as a freeloading passenger in another BAMA member's car (Mustangs Plus). I wasn't really planning on going to Fall Fest at all....but then Mike from BAMA invited me to drive his 2005 GT Fastback, and all I could say was a BIG FAT yes!

I followed Mike in his 69 Mach1 for the few miles to the show - I didn't really get the chance to feel the full potential of the GT, but it was very responsive, purrs like a real beast and has more than enough low end torque. Mike keeps the car in immaculate condition, including the raven black paintwork and unusual red/black interior.

BAMA were the only club invited to Fall Fest - we had about twenty cars out, including several I've not seen before. There was also a huge selection of American automotive history. The Fall Fest is essentially for cars built before 1972, but the organizers waived that particular rule for BAMA members.