In this article we will be rebuilding a starter for an SR. This can be a relatively straightforward and relatively inexpensive repair, if you have the time and patience. This article is originally from this thread:
Tools and Equipment needed:
8mm, 10mm, 12mm socket
Multipurpose grease (for lubrication)
Engine/Brake cleaner (for sludge and grime)
SOHC 89-90 KA STARTER
1: Do not open your SR starter until you’ve completely disassembled your KA SOHC starter – that way you’ll be familiar with all the parts.
2: Remove the two long 10mm bolts from the SR starter, and 2 from your solenoid. Spray and clean the black housing section with the green sticker. Over time it accumulates grime that hinders your motor’s spinning.
Note:The head should face down,because it has 4 gears that are unfastened, but they’re easy to put back on. Clean them with de-greaser and liberally apply fresh grease.
3: The base of the copper core for the electric motor is clamped in by brushes.
Note: The brushes are 4 small copper bars that press against the bottom of copper core. When you turn the key they send lots of current and spin the motor. Throughout the life of the starter they burn away and shorten, until they aren’t long enough. There’s a spring behind them to push them outward as they shorten but eventually it’s not enough.
When starters do not spin, its because these brushes have worn out. replace them to give your starter renewed factory life. Their plate is attached by two small Phillips screws from underneath.
4: Assemble the motor first, then replace the solenoid. The main housing of the starter won’t seal up and close properly if something is not aligned, so check everything before you tighten. I snapped a bolt by mistake this way.
5. Slide the starter pin into the new solenoid’s head and then push it back unto the U shaped spring. Make sure it snaps in, and lines up with the inset holes.
After a rebuild, it’s nice to know your starter will last for another 6-10 years.