As nitro-engine starting systems go, pull-starters are definitely the least desirable option. On the plus side, they’re cheap; on the down side, well, everything else. They aren’t reliable, they’re not comfortable to use, and if you’ve ever taken one apart, you know what a hassle it can be to get the spring-genie back into the bottle. Thankfully, there’s an easy way to replace a pull starter with much more convenient shaft starting, and that’s with a Sullivan Tiger Drive.
The Tiger Drive is simple. It replaces the pull starter with a pair of bevel gears, allowing you to spin the crankshaft and fire the engine using a 7/32 hex shaft. Once the engine is spinning, the one-way bearing in the drive gear allows the shaft to spin freely rather than spinning the Tiger Drive gears.
Installation begins by removing the pull starter. In this case, we have an electric-start engine, but it’s attached to the block just like a pull starter. Electric starting is much more convenient than pull-starting, but Tiger Drive still offers an advantage: reduced weight. The electric starter assembly weights 5.2 oz., compared to 1.6 oz. for the Tiger Drive. Removing three screws allows the assembly to be removed as a unit. With the starter removed, we can see the mounting holes and the exposed crankshaft.
Before installing the Tiger Drive, lubricate the gears. Sullivan recommends their Dry Ice lubricant, which doesn’t attract dirt like grease or oil. Slide the Tiger Drive over the crankshaft followed by the plastic cover, then install the four screws to secure it. Use threadlock on the screws, and tighten in a criss-cross pattern as shown to make sure the Tiger Drive is completely flat against the block and evenly tightened.
If you want to match the Tiger Drive cover to the rest of your car, Sullivan offers a six-pack of the covers in colors (S688). Or, you can get an aluminum version (S690) that helps provide additional engine cooling.
To spin the Tiger Drive, you’ll need a 7/32 shaft. Sullivan offers a starter shaft (S686) with an aluminum adapter to fit their Hi-Tork and Dynatron starters, but you can also use an electric drill to spin the shaft, as we are. A pair of 2mm screws secure the adapter to the shaft, simply remove them and slide the adapter off the shaft. Now you can chuck the shaft into a drill. Make sure you put the “plain” end into the drill. The ball end goes into the Tiger Drive.
To start the engine, just prime the carburetor and install the glowplug heater as you normally would with a pull start, then insert the shaft into the Tiger Drive and activate the drill. Note that the drill must be set to turn clockwise to turn the crankshaft; if it’s set to turn counter-clockwise, the one-way bearing won’t spin the shaft. Once the engine is running, the one-way bearing will allow the crank to turn faster than the drill, so there’s no need to yank out the shaft quickly.
The Tiger Drive system is easy to install and easy to use. It can help trim weight from electric-start models, and will greatly improve convenience, starting ease, and enjoyment of pull-start equipped vehicles.