Installing a Gear Reduction Mini Starter - 1967 Chevelle
The days leading up to an engine install are exciting. Exciting and loaded with last-minute things that need to be done or purchased to move your project forward. One of those things, for me, that brings a certain level of satisfaction is hanging the required components on the engine before nesting it down between the rails. Motor mounts, starter (if you can), flexplate, etc. It’s at this point when the new engine finally feels real.
I’ve found that, if you have the clearance to do so, mounting and adjusting the starter motor at this time is so much more enjoyable than doing it on your back under the car. So today I’ll give a brief tutorial of my starter installation.
I selected a Gear Reduction Mini Starter for my big block. My compression isn’t that high (about 10:1) but I’ve got a relatively small (Group 35) battery in the trunk, concealed in a retro cooler. For this reason, I wanted to extra grunt that a geared starter can provide.
As you can see by the product photos, these are a very versatile starter. They can be used on 153 or 168 tooth flexplates, they can also be clocked to change the position of the solenoid. Which can be very handy. The thing I like the most about them is how easy it is to check and adjust the depth into the ring gear on the flex plate.
On a traditional direct drive starter, you’ll likely need to remove the solenoid in order to extend the starter pinion gear into the ring gear to check clearance. As evidenced by the sound of some cars starting up at our local cruise-in’s, this is a critical check that many people miss. We’ve all heard the tell-tale high pitched crank or chunk and grind engagement of a poorly installed started. Don’t be that guy.
The old school method that I learned from my mentor and Step-Dad Bob was to keep a run of the mill paperclip in your toolbox. The clearance between the root of the ring gear teeth and the tip of the pinion gear tooth should be about .030” or roughly the same diameter of paperclip wire.
The gear on these starters already sticks out a little bit, even at rest. Which makes it pretty easy to grab and pull out so you can get a screwdriver behind it. Once you get it positioned correctly to mesh with a single tooth centered in the flexplate gear, unfold one end of the paperclip and poke the wire into the gap at the tip of the starter tooth.
If any adjustment is needed, it’s generally to loosen up this tolerance. In which case, you can install the supplied starter shims to increase the distance between the two components and measure again.
In my case the tolerance was just right and no further adjustments were needed.