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  1. #1
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    Proper Engine setback on alley cat

    Afternoon everyone. Have a question about proper engine setback for a 21' Sanger alley cat. The bottom of the sponsons angle back towards the engine. I have a hydraulic jackplate installed and when the motor lifts any more than 1" out of the water from my lowest setting the back of the boat starts to "feel loose" and unsafe. I will get exact measurements on the current setback tonight and upload pictures of the current setback. It seems like it potentially needs to be setback a couple more inches. What is recommended setback for say a skater or other cats in this size range with a single outboard?
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  2. #2
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    Not sure what set back u need exactly , how does it fly the bow? Plenty of lift? Loose is good for speed, but what I'm lookin at in pic is to deep I would think , u got water pressure guage?

  3. #3
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    Quote Originally Posted by Merc 2.5 View Post
    Not sure what set back u need exactly , how does it fly the bow? Plenty of lift? Loose is good for speed, but what I'm lookin at in pic is to deep I would think , u got water pressure guage?
    The bow flys alright when I trim up the motor. I believe I have decent lift but am not 100% sure. I figure the motor is a bit deep but if I Jack it up more than 1" with my hydraulic Jack plate it feels like I will loose the rear end. I do have a water pressure gauge but the engine does not have any thermostats so I only see a couple of psi of pressure do I always check my temp gauge.

  4. #4
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    Quote Originally Posted by summitrider1 View Post
    Afternoon everyone. Have a question about proper engine setback for a 21' Sanger alley cat. The bottom of the sponsons angle back towards the engine. I have a hydraulic jackplate installed and when the motor lifts any more than 1" out of the water from my lowest setting the back of the boat starts to "feel loose" and unsafe. I will get exact measurements on the current setback tonight and upload pictures of the current setback. It seems like it potentially needs to be setback a couple more inches. What is recommended setback for say a skater or other cats in this size range with a single outboard?
    Sounds like a fun boat! What speed are you going when you have concern that the boat starts to "feel loose"? what is your MPH, engine, prop, RPM at top speed? where is engine height set? Pics of the boat when running might also help?

  5. #5
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    with a single raising to high on heavy hull you will lose bite is what your feeling

  6. #6
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    Quote Originally Posted by Jimboat View Post
    Sounds like a fun boat! What speed are you going when you have concern that the boat starts to "feel loose"? what is your MPH, engine, prop, RPM at top speed? where is engine height set? Pics of the boat when running might also help?
    The loose feeling is not speed related. My boat is setup with cable steering and when the motor is jacked up any more than 1" I have over half a turn of steering play without changing direction. It doesn't not lose forward bite but loses all steering. It doesn't matter if I'm going 30mph or 60mph it has no steering control with the motor jacked up just 1"

    I am in Denver and have only seen 65mph on GPS. Currently testing with a 21" prop. The 65mph was with a 24" taker prop @ around 5800 rpm.

    Motor is a evinrude 300 v8.

  7. #7
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    Quote Originally Posted by summitrider1 View Post
    The loose feeling is not speed related. My boat is setup with cable steering and when the motor is jacked up any more than 1" I have over half a turn of steering play without changing direction. It doesn't not lose forward bite but loses all steering. It doesn't matter if I'm going 30mph or 60mph it has no steering control with the motor jacked up just 1".
    Oh, i now understand what you're saying. it sounds like your cable steering isn't set up to maintain tension with motor movement. This can be dangerous. It sounds like your observed "looseness" is not due to engine height or propeller selection so much as it is due to the cable steering going loose. Needs to be set up so that it's always tensioned. Also, engine height looks too low, currently, to me.
    Last edited by Jimboat; 09-01-2019 at 11:35 AM.

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