Captalbertq
Well-Known Member
- Joined
- Dec 2, 2013
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Earlier this week when I started my Stromberg carbed A65, I noticed the idle mixture was very rich. When throttled up the engine would clear. I continued with my flight but after landing the engine loaded up with fuel and began to run rough again. Today I took the cowl off to investigate. First I attempted to lean the idle mixture with no results and on shut down saw fuel dripping from the heat box. Shoot, time for needle and seat repairs..but fuel stopped dripping when the engine was shut down? I thought about what could cause the engine to pull all that extra fuel in; cracked housing on carb? Metering jet fell out? Then it dawned on me and I looked at the primer. It was unlocked an out slightly. Primer in and locked, engine purrs! The vacuum at idle was sucking fuel directly into the intake manifold through the primer circuit. I wonder how many idle starvation issues might be caused by an air leak in the primer line to the manifold causing a lean mixture?
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