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Carb. problem

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EAABipe40FF

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I have a MA3 SPA on the O290 on the Spezio. It started acting a bit funny the last time I flew it which was almost 6 weeks ago. The throttle seemed stiff and after flying around to get the oil temp up I noticed that performance was off and I could barely maintain cruise RPM so I got it back on the ground. On the ground static RPM was only 2100-2150, down from normal 235o or so. I suspected a throttle linkage problem although on 2nd thought had no reason for that. It was cold so I put it away for another day.

Today is another day, finally got a warm day when I wasn't fixing broken trucks. I didn't run it but dived into the linkage removing cowl and boot cowl.

Bottom line it's not the linkage but the carb. itself. Push the throttle forward and it seems to come to a hard stop about half way(with linkage off throttle arm). But then wait a few seconds and you can push throttle open to the stop. It seems to be the accelerator pump? Maybe? I'm having severe back issues again and by this time I was done for so I didn't remove the linkage from the accelerator pump to confirm. The acc. pump was working, by this time gas was running out. But each time I worked the throttle it came to a relatively hard stop....wait a moment and it would easily move forward to the stop.

Any ideas? I've taken MA-SPA's apart and put together before but I don't think I've ever had the accelerator pump apart so what might I look for?

Thanks,

Jack
 

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