Crab trapped!

[fritzmerde]

The other night my son & I had his 10' alum. boat with a little 5hp. Briggs outboard out fishing. We came to abrupt stop & the engine died. We had a crab trap line wrapped around the prop. The crabbers aren't supposed to put their traps in the narrow channel but they do, and usually it isn't a problem, but we hadn't spotted the buoy & bang. I hopped in and cut away the thin tubeular line. It was wrapped around the shaft big time and took quite a while to cut it all off. I got back in fired it up and we went about our merry way. My son took it out the next day and said something was wrong with the engine. I took it out last night and he was right. It starts and runs fine but the tranny seemed to slip and there is no power, I went to full power and the boat didn't even get up on plane. Depending on the tide and waves it usually runs between 12 to 15 knots-I got 5 knots out of it. Any help would be greatly appreciated, it starts and runs fine, the prop spins freely, the blades are fine, but the engine power isn't getting to the prop-thank you in advance.

 

[grandpaclint]

you should remove the prop and look for more line

 

[Chris]

Sounded like fun time until the crab line showed up!

What year is this engine? Some older models of outboards had what was referred to as a "shear pin". Essentially what a shear pin did and was, was it was a sacraficial metal pin, then would break when your prop encountered an underwater object so that you didn't break a gear in your lower unit or break or bend your prop shaft.

Assuming your motor doesn't have a shear pin, I would pull the prop off and look to see if there is any more line on the prop shaft or inside the hub of the prop. Assuming there isn't, I would then look inside the prop to see if there is any indication that the prop hub is damaged or that it is now slipping. Unfortunately, with prop hubs, it's sometimes not really possible to totally tell whether or not it's slipping, but sometimes you can. Typically, the best backyard mechanic way to diagnose that issue, is to try a spare prop and see if that cures the problem. If it does, then it's a safe bet you're spun the prop hub loose on it. If it doesn't, then you're most likely looking at something broken or damaged in the lower unit somewhere.

Hope that helps a bit, if you have any more questions post 'em up.

Let us know how you make out.

-Chris

 

[fritzmerde]

Thanks Grandpa & Chris,
It's a B&S 08 model. Last night I pulled the prop thinking I had spun it and maybe had torn up the rubber coupler. There's a 1 inch gap between the metal coupler and the seal where the output shaft carrier exits. There had to be 10 yds, of 50lb line and some sort of spring partially intact and the rest pulled around the shaft attached to what looked like 550 chord. I can't believe that it spun at all. The only damage I can see is to the seal mentioned previously-I think the spring cut it up. Sadly my skills as a mechanic are nil. I just hope that I didn't add to the damage. I'll give the B&S folks a call and find out what needs to be done. I'm still kicking myself for not pulling it right away. I'm normally perfect so I'll put this down as the 2nd thing I've ever done wrong-it's hard to be humble,that's me a humble genius-do I need foot notes-my boys are watching under dog and I just stole that line-so SNAFU-thanks much for the input. I'm on the water almost everyday-there is nothing better. Thanks again, Fritz