No thrust on 1957 7.5hp Evinrude

[BryanL_FL]

Engine ignorant sailor needs some help...<br /><br />Have an old 1957 7.5hp Evinrude motor, was running great until i went aground (probably never heard that before).<br /><br />Now the engine starts normally and runs fine, but i seem to have lost all the thrust ...<br />Have to crank it wide open to get any forward movement from the little guy. I assume that I broke/jarred something in the lower unit, but just not sure what to look for...or if I should even try...<br /><br />Any suggestions?<br /><br />Thanks so much!<br /><br />-Bryan

 

[JB]

Re: No thrust on 1957 7.5hp Evinrude

Hi, Bryan.<br /><br />You probably have broken the shear pin in the propellor drive.<br /><br />Remove the prop. You will find a pin that goes through a hole in the propshaft and fits into two grooves in the prop body. It is probably now in three pieces.<br /><br />Replace this pin ONLY with the correct pin, from a JohnnyRude dealer or NAPA Auto Parts Store. <br /><br />Be sure to get a couple of spares while you are at it and Duct Tape at lease one inside the engine bonnet for easy access and replacement when it happens next.<br /><br />Good luck.

 

[Chinewalker]

Re: No thrust on 1957 7.5hp Evinrude

Hi Brian,<br /> Go for the easy stuff first. <br /><br /> Have you checked the shear/drive pin? It's located under the rubber propnut.<br /><br /> Secondly, and most expensively, is your motor has a two-piece driveshaft. The lower part has a spring shock absorber that is supposed to absorb shocks such as the one you descibed. This spring can break if it's hit hard enough. They're getting difficult to find, but there's a fix that involves getting the lower shaft parts welded together. You then have to use a softer shear pin to prevent samage to the drivetrain should you hit an object in the future... To check this one, remove the spark plug wires from the plugs. WIth the motor in gear, try turning the propeller. If you can feel the gears moving but they don't turn the motor over, you may have a broken spring. Or, if they move freely on one direction, but bind up in the other, that may indicate it, too. Disassembly is the next step...<br /><br />- Scott