How To: Delorean Factory Motorola Alternator Restoration

[jcrubin]

While Elvis and I were working on the car cleaning grounds and connection in an attempt to solve for some electrical issues, i'd noticed a visual indication that there was trouble with the alternator. No doubt potting material is deteriorating. This alternator will need to be removed for evaluation and repair.

With a standard de-installation and a minimal amount of mistakes; having the unit on the bench we see that there will be some issues with loosening screws that have galvanic-ally corroded over the years. Some are a lost cause as we see with the capacitor, needing to be ground down and machined later.

With that out of the way, removing the removal of the plastic shroud makes it clear that most of that potting material has ended up in the cooling fins of the lower side of the rectifier. Cleanup, if possible, will be extensive. It was almost no surprise, but still quite amazing that the voltage regulator was all but empty, having completely melted out.

I spend some time with the shroud and various chemicals to see what responds to the residue. Turns out throttle body cleaner seems to have an effect on it.

Next I remove the the nut and pulley with standard tools and procedures ensuring everything stays in order. This is followed by the brushed, which I have about a fifty percent success rate removing the screws. The brushes removed however looked surprisingly good, i will most likely reuse them.

I then remove the four bolts that secure the assembly, and the 3 screws that hold the front bearing into the race. Though, I'm running out of special alternator tools, so, its off to Jason for some special tools for the job.

Behind the scenes there were some discussions about how to remove certain things without damage, some procedures were standard fare. Some setups for pulling bearings out of the races were total custom setups. Both bearings, upon inspection, were more than ready for replacement.

Once separated cleaning was started, the front cover was sand blasted. After that, all of the broken screws were drilled out on the press. It was then cleaned with a variety of chemicals. Brought home the last hole was tapped to 4mm and the brushes test fit.

At this points with two new bearings ordered we end this episode here and wait for parts arrived for test and assembly in the next episode.

[jcrubin]

The second half of the video continues off with the disassembled,cleaned and stripped factor alternator of the Delorean. With the bearings arrived I toss them in the freezer while I prepare. I removed the sticker on the side before going down to the bug ranch so it would not get damaged. Starting off, the entire housing was taped off. Since it cant be sand blasted, I opted for a wire brush on a drill press to clean up the aluminum. I also used to to break up the dullness of the blasting on the top cover from last video.

I prep the press for the installation of the bearings, starting with the top cover first. Using original NTN bearing 6203LLU. Minor lubrication of the race was done to stop any galling. with the bearing installed I tape and prepare with acetone for clear coating, with high-temp clear coat. I them prep the bottom portion for bearing installation this time with bearing 6200-2Z as well. The bottom is also prepped and clear coated in the same manner.

While the two main housings were drying I sandblasted all of the brackets nuts and bolts and sanded the ground of the capacitor. After this the bearing retainer was reinstalled with blue locktite. The rotor was then pressed into the top cover bearing to full seat. I stopped there because I wanted to do a few things, I nickel plated all of the small parts, also, I wanted to varnish the exposed wires of the rotor, so I took some time out to do so.

Back at the shop I take time to discuss what I feel would have been the correct disassembly procedure for video 1. This would have been with the bolts removed first tapping out the back smaller shaft through the small hole with a drift, and then leaving the front bearing retainer alone, pressing the rotor out of the top housing.

Continuing, I apply a thin coat of anti-seize to the circumference of the top of the mating surface of the main housing. The halved are brought together on the press and pressed together only slightly so the top still rotates, then removed from the press so that the bolts can go through as a guide, back on the press and brought to full seat. Off of the press the four bolts are tightened down with blue locktite.

The brushed are reintroduced into the unit, all screws receive anti-seize, this is followed by the installation of the new voltage regulator, and then the plastic shroud. With that the front parts for the fan and pulley are reassembled to the alternator. The nut up front got blue locktite on the threads and was torqued to 30ft/lbs

At this moment I realized I never checked the capacitor and realized it was bad so I had to stop and over one from England. Once it arrived I installed it and the alternator was ready for installation. This is done in the reverse process as removal though the main mounting bold is covered with a light coat of anti-seize. Once the installation is completed the car is started, monitoring only the mechanical portion of the work. Noises, breaking things, fires and whatnot.


Finally, everything is tested with the fluke meter under a variety of loads connected to the battery terminals. This, with a weak batter, using a combination of internal fans, headlights, and cooling fans showed that while the alternator doesn't pack a punch, it has significantly improved with this restoration calling the work a success.

[jcrubin]

From rafael

Along with a Gates 7485 Belt

https://www.amazon.com/gp/product/B0...Q-iHe_TrntHoPY

[Ron]

...Moved to How-To Guides

[David T]

Where did you order the parts, what part numbers did you use, was it a kit, and what did it cost? If it was a kit what was included?

[dmcnc]

Where did you order the parts, what part numbers did you use, was it a kit, and what did it cost? If it was a kit what was included?

I think he replaced individual items - for sure the Regulator, brushes, bearing and capacitor.

Regulator:
https://www.ebay.com/itm/REGULATORS-...72.m2749.l2649

Brushes:
https://www.ebay.com/itm/Brush-Holde...item1a7a36fc76

Capacitor:
https://www.ebay.com/itm/Capacitor-f...72.m2749.l2649

And I can't remember the specific bearing types...but I'm sure Jordan can chime in.