Deep Despair with the Differential!



2/8/02
Deep Despair with the Differential!


This is something you don’t want to see coming out of the a car, especially a Ferrari, a Ferrari differential to be exact! It all began today when I decided to drain the differential to get it ready for the fresh gear oil I ordered through the mail. I got out a 24 mm wrench and loosened the drain plug. As I slipped the catch pan under the diff, I heard the strange sound of running water, and not the familiar “gloop, gloop” sound of gear oil filling the catch pan. About a quart of clear water came out, followed by a tiny bit of gear oil! I’ve heard of condensation forming a bit of water inside a gear case, but there was no way this much water could have gotten in there. François was as surprised as I was, and equally disturbed.

First off, the only theories we can come up with is this car had been submerged, or flooded at some point in it’s life. Deep water would have easily gotten into the vent tubes in the diff, and forced the oil out. The only other possibility is someone actually poured water into the differential! Whatever the reason, I’m faced with a real job!

Draining all this water out, and refilling it with gear oil would not even be an option. We discussed what could happen, and even the slightest problem could turn catastrophic. The main concern is rust on the bearings. If the bearings got rusted inside the differential, they could seize up, shatter, and send bits of metal into the ring and pinion breaking those as well. Replacing the bearings are cheap when compared to how rare, i.e.. expensive, a new ring and pinion can be. Unfortunately, this means at the very least, some of the rear suspension will need to come apart.

The plan is to take one axle tube off the differential to have a look inside. If it looks like chocolate mayonnaise and rusty bearings, the rest of the rear axle will have to come out. These parts are not going to be easy to unbolt because they probably haven’t been touched since the car was built! I immediately skinned a knuckle on a frozen cotter pin, so I’m not happy! Just when I thought I had this restoration in its final stages…!

Earlier in my day before all this bad news, I was prepping my wire wheels for the spoke tape I bought from Hendrix Wire Wheel. The roll they sent me (left side of the picture) was plenty to do all five wheels.

Although all my wheels have been refurbished, some of the insides of the wheels showed a lot of gunk and tape residue that I wanted to remove. I scraped, and cleaned the surfaces with acetone to give the tubes a nice smooth surface to prevent punctures.

I wrapped each wheel with four layers of tape to keep the spokes from cutting into the tubes. I tried to find this type of tape locally, but couldn’t find any, so I ordered it. At about $14 bucks a roll, it saved me time and gas driving around looking for it. If you see a wide PVC type tape, it’ll probably be the same stuff.

All five wheels were soon done, and are waiting on my decision as to which tire I’m going with. Stay tuned for the decision. Cork Adams called this week to tell me that he has removed the old chrome plating on my knock offs, and only one of them needed to be re-engraved. Hopefully I’ll have them back in a couple of weeks!

Now that my exhaust is largely done, I wanted to complete some of the small details, one of them being the paint inside the tips. The original Ansa tips had an orange paint applied to the inside of the the resonator tip at the exit of the exhaust. Now I know the first few hundred miles of driving this car will probably leave black carbon deposits on these resonator tips, but I believe a hint of orange will always be seen, so I masked the tips for painting and used Hi-temp “Chevrolet Orange.” paint.

Looking for other details to complete on the car, I addressed the missing engine timing cover plate. Vintage Ferrari engines have their timing marks on their flywheels. It’s a pretty accurate system because if you can decipher all the marks, you can tell precisely which cylinder is doing what throughout the rotation of the crankshaft. Engraving all these marks on the smaller front pulley would have been impossible. You can see the small access hole in the center of this picture with a pointer. Common to old Ferrari engines, the flat aluminum cover was missing on my car. I made one using a template François had from the many he’s had to re-make over the years. (Yes, I know, I’m using a non concours hose clamp on the vacuum line, so please, no letters!)

After cutting the rough shape of the cover with aviation shears, I filed it down to the exact size. Although the original thickness of the cover was thicker, I used what I had laying around the shop. It’s only really there to keep debris out of the flywheel area, so any thickness will work fine as long as the acorn nuts holding it in place don’t bottom out.

Here’s the final product. Notice my slightly dirty, but undamaged hands. This was well before I started covering them with WD-40, penetrating oil, dirt, and blood from my skinned knuckle working on that differential!

On the other side of the shop is the 312 F-1 car François is preparing for a customer. I’ve mentioned it before, but I wanted to show that it’s really coming along. Watching this car come together has been a history lesson in racing. This is a 1968 F-1 car, and some of the technology, though common in its time, has been fascinating for me to learn. For instance, to save weight, some of the tube frame chassis is used to carry coolant from the radiator to the engine! Now that’s fine for a new race car, but you can imagine what that can do to a 30+ year old car if the steel tubes were allowed to rust from the coolant inside! Luckily, this car was very solid.

Another safety issue that would not pass any modern race car rules is the roll bar bracing. If you look closely, you can just make out two thin silver braces coming down from the center of the roll hoop. These braces, thin and hardly strong, are bolted to the valve covers of the engine!!! François has actually seen a similar set up involved in a rollover, and says the hoop itself is very strong, but the bracing was really a joke. Although the hoop collapsed a few inches from the broken bracing, the driver was safe. Not the same could be said for the engine because the steel support tubes broke through the magnesium covers with ease, and ruined the valve train! If I remember, I’ll take some detailed pictures next week!