Flying at 6000' near my home field last weekend, I noticed that coolant temp was climbing past 230F.  I descended at idle and landed normally.

Investigation shows that my smog pump (used for vacuum) had seized. With the clutch released it turns normally. Close the clutch and it locks up solid. This took out the serpentine belt  (melted and charred where it spun on the engine pulley), which obviously took out the water pump and alternator. Not what I'd call a benign failure mode!

I plan to get rid of the smog pump in favor of a Dynon or similiar, but will need an idler gear to route the belt. The alternative is to replace the smog pump, then just let it idle when I install the electric attitude / giro.

Does anyone have a 2nd gen smog pump they'd like to sell?

John Slade
Turbo Rotary Cozy IV
81 hours.