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77 evinrude 25hp short shaft troubleshoot question

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bearclaw360

New member
Hello fellow boaters! I have a '77 evinrude 25hp short shaft outboard that I hit a log with unfortunately. anyways upon inspection I noticed whoever had before me used a steel pin for "shear pin", which only bent. I replaced the lower housing which had cracked, sealed it, fluids etc. put a new prop on it, made sure it was shifting gears ok which it was, and then started it. it runs great, but the prop doesn't turn. I only ran it for a moment. I'm expecting it to have sheared something else off etc. but figured before I started tearing it apart I'd ask some pros. is there an upper shear point? or another likely place to start looking? is the drive shaft stripped perhaps? any help is much appreciated. Thank you!
 
First of all it is NOT a brass shear pin in those.----Factory installed a steel DRIVE PIN in them.----Props have a rubber hub in them that is supposed to give or slip.------You stated it shifted gears OK but yes the driveshaft could be broken.-----Or splines at top of the shaft stripped.----Easy to drop lower unit to inspect this stuff.
 
racerone said:
First of all it is NOT a brass shear pin in those.----Factory installed a steel DRIVE PIN in them.----Props have a rubber hub in them that is supposed to give or slip.------You stated it shifted gears OK but yes the driveshaft could be broken.-----Or splines at top of the shaft stripped.----Easy to drop lower unit to inspect this stuff.
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thanks for the speedy response! I'm surprised that a steel pin was used. I'd have guessed bronze...oh well anyways Good to know that it's not too bad of a job to drop the lower, I'll have to research that. I'm assuming I could find the shop/owners manual on this forum? thanks again for the confirmation!
 
They started using steel drive pins because changing pins on bigger motors is nearly impossible out on the lake or river.-----Of course you can use a brass pin and be prepared to change it.-----Brass pins were also damaged during shifting.----Brass pins lost their popularity so to speak !!!
 
thank you very much, that makes sense. I'm gonna try a bronze one since it shifts well and idles down really nice. we'll see. turns out the very top portion of the upper drive shaft got cut right off. gonna take the powerhead off today and try to remove the broken piece, get it ready for a new shaft. just gotta find the right one now, it's a model no. 25702S, serial no. E0005625. i'll check the parts guide on the forum to start. Thank you again for the help, your knowledge really helped point me in the right direction!
 
yeah sure is...I'm in muskegon, MI. the part no. is 0325800. if you could find one that would simply be amazing! thanks for all the help so far!
 
I am about 6 hrs away from you.----I am quite busy in the summer.----I have a large assortment of driveshafts on the shelf-----But it takes time to check / measure find the right one if I have one.-----I believe it might be a " one year only " item.
 
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