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  1. #1
    Join Date
    Jul 2022
    El Dorado, California

    Default 115 Will Not Run To Full RPM Even With Prop Changes

    I am breaking in a new engine, the 19p 4 blade prop runs great, but the wide open throttle didn't seem like it would go past about 5300rpm...

    So I tried a 17p 4 blade knowing if the engine were at an all out peak with the 19p, I should have seen an increase of upwards of 400rpm with the pitch change...but I'm seeing the same exact 5300rpm which would tell me the throttle is being limited in terms of full input, the engine has not run out of steam as it would be at a true WOP.

    Not okay as far as I'm concerned not to be able to find the exact right prop zone I want for one thing, it's how the engine should be performance tuned for the right prop.

    Anyone hear about or know how the extra throttle input is tuned? The throttle lever has plenty of room to move an extra inch or two but the increased throttle is stopped by the throttle mechanism and being kept from extra input.
    Last edited by woodguru; 07-17-2022 at 08:14 PM. Reason: clarification

  2. #2
    Join Date
    May 2015

    Default Re: 115 Will Not Run To Full RPM Even With Prop Changes

    What motor do you have? Need a serial #. O5herwise it could be a 3,4,6 cylinder motor. Is it carbed or injected

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