This wonderful 1275-powered racer came to us with a vexing problem… it ran fine in the paddock, and after nearly a lap, she began to break-up and eventually stall.
We started with the basics… ignition, timing, fuel, etc. When we went to check the valve clearances, we found that one rocker arm had popped out of the pushrod (see photo below).
Binding guides would do that. As the guide heats-up, it constricts the valve stem, the valve timing goes wonky, the engine gets quite confused as the valves start dancing to a different drummer, and you’re done. We have seen this before on road cars. The jumped-out rocker was a good clue.
We removed the head, honed the guides (which were definitely too tight) and built it all back up. The push rod was bent at the site of the pop-out, so we changed those. We also removed the plastic oil pressure gauge line and replaced it with a copper one, which you can see below with the proper shock coil for vibration.
Next, we tightened everything up, re- tuned, then went for the ride shown in the video below. As you can see, now this racer is ready for full track session.
A Spridget is an awesome first race car. Their easy to use, forgiving, and relatively easy to fix. Everybody needs one! (And vintage racing needs you).
We’ll keep looking for more race cars we can sell. This one lives near Lime Rock Park in Connecicut and the owner’s dream is to run in the Labor day Fall Festival this year. We hope to see him there!