DIY Guide to Polishing Your Own Alternator


The alternator is a very visible underhood part. If you frequently polish other engine components, the alternator can be an eyesore. Unfortunately, polished and chromed alternators can be quite expensive. Why not polish your own alternator? Following this guide will make the process as painless as possible.

Alternator Polish Prep Work

removing the unit for preparation

Before you start your project, use some penetrating oil the night before on the pulley nut. It is best to break the nut loose while you have the tension strength of the belt to assist you. Use a towel to grip fan blades and carefully break loose the pulley nut. You may have to use some wedge device to lock fan from turning, just be careful not to damage the blades.

component guide

After breaking loose the nut (#6) your parts should come right off without any kind of puller. Go ahead and polish the pulley until it matches the photo. This photo can be used as an assembly guide in case you forget the order.

initial alternator polish

Starting to Polish Your Alternator

Remove the four screws holding the front and rear housings together. As you begin to polish down the casting marks on the front alternator housing you will encounter several grooves where the front to back housing screws go. This image shows the stark difference between a light polish and the original rough casting.

guide wheel example

Use an expander wheel and trizact belts to make shorter work of polishing the casting marks off and smoothing up the finish. The alternator has plenty of really "linear" surfaces so the project is not really that difficult. Just let the natural lines of the case be your guide.

guide to housing crevices and trouble spots

One more closeup of the groove you are removing. There are four of these on the front housing.

polish guide, linear surfaces

Note: You might have trouble separating the rotor and bearings from the front housing. This isn't a problem, but it will make for a little heavier work. Take an occasional break if it becomes too arduous.

The bottom arrow shows casting marks removed and the top shows a faint casting groove still in place. The center part where the shaft goes is covered by the pulley so you have a wide area that does not need detailing.

alternator polish guide results

Here is a close up of the groove removed and polished. Isn't that much better? There are a few areas on the housing that a indention or raised area can be leveled. On the top picture you can see that a raised area (where the top and bottom mounting bolts go) has been knocked down.

alternator case before

On the back housing there are many very linear surfaces BUT there are some challenges too. These grooves aren't going anywhere. Use a sanding taper and dremmel tool to smooth out the casting marks.

CS144 housing slip ring end

Preparing for Section Two of the Guide

This will be a major challenge on the back of the rear housing. Too many raised and lowered surfaces prevent you from getting a trizact wheel evenly onto the surface. Unfortunately you will have to find your own solution for detailing, as every housing is a little different. Remove the bracket and get started with section two of this guide.

cs144 electrical components

Nuts marked 1, 2, 3 hold the stator in place. Remove these and take out the stator. Put the nuts back on the rectifier post so you don't lose them. Screws 4, 5, and 6 hold the rectifier in place. Loosen them, but don't take them out completely. #7 is the battery post, it goes all the way through the housing. Remove the nut, pull the battery post out, and secure the nut to the freed battery post. Screws 8, 9, and 10 secure the voltage regulator, loosen them completely, but don't remove the regulator just yet. You are now prepped for section two of this guide.

Polish Your Own Alternator - Part 2