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Engine Troubles

rrb

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Joined
Mar 23, 2005
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Today I took the Cruiser out but aborted a takeoff because the engine didn't accellerate properly -- it was like it stumbled / or had lower power for a second and then accellerated through it, i did it a second time and once it got up to speed noticeable problems. My oil temps were about 100 and my pressure was normal. I didn't notice anything unusual during my runup. The A-75 overhaul manual for my engine lists the following possible causes:

a. motor not sufficiently warm (I allowed the oil to warm to about 100, the manual lists the minimum takeoff temp at 90)
b. heater control not on, or not functioning properly
c. spark plugs fouled by long idling (i think this could be an answer, but wouldn't I have noticed the fouling too when checking the mags -- i did idle for a while trying to get the oil temps up, still running 100 weight oat about 50)
d. high float level
e. warn intake valve guides and piston rings

Any thoughts? With the short days, I'll probably call a guy to look at it, but wanted to get some advice before I did.
 

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