Dy-No-Mite

I had a good reason to clean up the engine bay.  (Oil everywhere will do that.)  It was easiest to remove the generator to get to the bits that were underneath.  I figured, "Well, it's out... let's take a look."

Lucas C39/C40 dynamos (generators to us Yanks) are pretty simple devices.  I've rebuilt this one already, and it was working fine... aside from slightly low voltage output at idle.  It was also making a bit of noise at the rear bushing, which I figured was probably on its way out.  I had not replaced it.

Here's the complete teardown of the dynamo.  Teardown isn't difficult.  The hardest part is using a small puller to separate the armature from the front plate's bearing.

I could see something I didn't like.  The armature rear spindle is really scored.  It wasn't this bad a few years ago, but there was wear.

A little research on the Googles shows these are readily available.  Since C39/40 dynamos were used in everything in the 50s and 60s, even farm tractors (!), I found a replacement armature at a tractor supply store for $75, and brushes for $12.

The new armature is a nearly perfect fit dimensionally, being just a tad longer at the rear spindle.

I also ordered a new rear bushing.

Replacing the rear bushing isn't difficult, but takes a bit of care.  Knocking the old one out was as easy as getting a thin screwdriver between the bushing and the housing, and then pulling it out with a needle nosed plier.  (It was a LITTLE harder than that, but the bushing is copper and will bend/split with some persuasion.)

The bushing is actually three elements: a felt pad that holds oil, a retaining plate for the felt pad, and the bushing itself.  The pad goes in first, followed by the plate (with the concave side toward the back), then the bushing.  The retaining plate has little slots in it to let the oil ooze past it and onto the bushing.

Driving the new bushing in in was a bit of a chore.  I sanded the outside of the bushing down a tad to get its outer diameter closer to the inner diameter of the hole, and then put the bushing in the freezer before tapping it into place.

Once in, I had to gently ream the bushing out a bit to gain enough clearance for the new armature to spin freely.  I also slightly modified the rear spindle on the armature to make it a tiny bit shorter and gave it a taper to clear the retaining plate.  This took some trial and error and a few test fittings to get right.

After all that, I filled the bushing with oil and let it soak down, repeating a couple of times over the course of a day so the bushing had a chance to soak up oil.  I had soaked the bushing before as well.

Reassembly is straightforward.  The armature goes back into the front plate, then is assembled to the main body, followed by installing the rear plate.  There is a trick to installing the new brushes:  Install the brushes, and push the retaining spring to the side of each.  That holds the brushes apart so the rear plate can be installed to the armature and body.  Then, flip the little springs to have them push on the back of the brush.  This makes a real chore take about 30 seconds.

After some paint, she's done.  Spinning by hand makes a couple of tenths of a volt, so I am pretty sure it's going to work.

I painted the generator body green as that is what it should be on a '65 (I had painted it black).  I painted the pulley and fan black, even though they should be metal, just because I wanted to.  I think it looks great.

Hopefully, that's a job done for another few decades.  With regular oiling, it should last a long time.

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Where's that Oil Coming From?

I went for a short drive a couple of weeks ago, and Something Happened.

It wasn’t long, just up the road a ways to the gas station to get an ICEE. When I pulled out of the parking lot, I saw some oil on the ground. I thought, “Boy, someone’s losing a lot of oil.” (I’m no Joe Friday.) “It’s not me, though.”

Oh, but guess who it was. It WAS me. I got home, pulled into the garage and saw a trail of oil following me home.

It happens that the oil pressure gauge line cracked and sent a quart or so of fresh, clean Castrol all over the inside of the engine bay and down to the road.

Well, it’s an easy fix, at least. Parts are on the way and everything’s clean again. So, she’ll wait a week or so.

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Cutting and Buffing and Bears, Oh My!

Well, it was bound to happen eventually.  Someone gave me a little tap a couple of weeks ago, and I ended up with some damaged paint and chrome.  Nothing serious, but frustrating...

I had to fix two major spots: One on the driver's side of the bonnet and one around the passenger's side headlamp.  The paint cracked, and if left unrepaired would eventually flake and be prone to rust.  And I knew it was there.

Along with a new grille and chrome surrounds, and a new turn indicator lens, the only damage was to Gidget's pride.  And paint.

So we fixed it!

Here's what needed fixing.  It doesn't look like much, but there was quite a bit of work involved to do it right.

Like I said, not too bad.  But to fix it means removing all the damage... which in this case went down to the metal.

We ("we" is me and my friend Mike) started by removing the grille and surrounds, turn indicator and headlamp, and mirrors and antenna.  Mike decided that the only way to fix the cracked paint on the wing was to re-clearcoat the whole thing, otherwise there would be a blend line that would be visible.  Then, he sanded out the cracked filler on the bonnet and reapplied a lightweight filler.  After a coat or two of primer, it was smooth and invisible (aside from the color, that is).  He also sanded down the crack on the wing and was able to primer without a need for filler.

Once dry and sanded, we sanded the clearcoat on the bonnet and fender.  He taped off the parts that didn't need paint and made the problem go away.

Now watch this.  Coat by coat, the problem area disappears.  He wiped with a tack cloth in between each coat.

Then he applied three coats of clear...

Wow.

After drying, the fun part began.  That's the subject of this article, actually--the fun of color sanding, cutting and buffing the finish.

Color sanding is the art of taking a perfectly good looking finish and making it look even better by first making it look terrible.  You actually sand your beautiful looking clear coat to get rid of all the imperfections - "orange peel" and "fisheyes".  Do do this, you need sandpaper in increasingly fine grit (starting at 1000), and an orbital sander.  I prefer a "palm sander" as it is easy to control the pressure and speed. 

I started with 1000 grit and lightly worked the surface to remove some orange peel and get things very smooth.  I used slow, steady passes with the sander running at a moderately slow speed.  From there, I went to 3M Trizact pads in grits of 1500, 3000, and 5000.  Trizact pads are to be used damp, so I lightly misted the surface each time and wiped clean in between.

At each stage, I lightly went over the surface until I covered the whole area.  The finish gradually improved until after the pass at 5000 grit, there was actually a hazy shine.  5000 grit is almost like using copy paper as sandpaper.

Once sanding was done (and I did go back a few times to correct more things), it was time to "cut".  Cutting is the application of a compound to start removing the scratches left by sanding.  Here's a couple of shots halfway through a pass to show how quickly the finish improves.  I started by using a wool pad, then followed with a pass using a foam pad designed for use with compound.  I used Meguilar's products for this stage.

Once the passes with the compound were done, I moved to "buffing" with a polish.  You can't really tell too much from these photos, but under brighter light you can see the scratches disappear.

Finally, I finished with a very fine 3M polishing compound and then some Griot's Garage spray wax.

I wrapped up by reinstalling all the chrome surrounds and mirrors, and a new grille from AH Spares.  I treated Gidget to new mirrors and some fancy bumperettes from a Bugeye Sprite.  I made custom brackets and installed a pair in the front, too.  I think she looks sharp!

I call her my tiger cub. :)

I did find a bunch of things to fix, since I am not super skilled at this.  I'll fix 'em.  It's not hard and really is mostly a need for good lighting to be able to see the flaws at the time.  The first time I did this during initial assembly, it took me a week.  This was a few hours.  I'm still very happy and Gidget is better than ever!

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