I hit a dang log!

[HappyHillbilly]

Howdy,<br />I've got a '79 Johnson 140 on an '85 - 16ft. fish & ski Procraft.<br /><br />I hit a barely floating log the other day going about 35mph. I saw it at the last minute with no time to react other than keeping it straight but I'm not sure if I hit the log square or not because there was other debris around it. <br /><br />The motor now has a slightly stressed sound & instead of a rooster tail, the water kicked up by the motor is now more of a violent churning type that forms right behind the motor. The motor seemed to be a little hotter than normal when I cut it off but still had a strong pee stream.<br /><br />It didn't hurt the prop and there's no visible damage to the lower unit or anything else that I can see. I think there's damage because of the change in the way the motor sounds & the big churning of water in place of the rooster tail.<br /><br />Where do I begin? What are some possiblities?<br /><br />Thanks!<br />HH

 

[willamettejeff]

Re: I hit a dang log!

Three things come to mind. Are you sure that prop isn't damaged? Eventhough no edge damage one or more of the blades could have been bent slighly. Or you may have spun the prop hub or bent the propeller shaft. I mostly boat on a river and it seems hitting a log now and then is just a part of it. I sure have come to know that "stressed" sound as well. Fortunately, all I've managed to do is bend a few props.

 

[sycamore]

Re: I hit a dang log!

Is your boat at dock and not on trailer? If still in water, you might have damaged your boat and now the water is leaving the back of the boat different. You may of gone from a rocker to a hook, or vise versa.

 

[HappyHillbilly]

Re: I hit a dang log!

Hey!<br />Boat is on trailer here at the house. I can't see any damage, at all. Prop or anything else. <br /><br />With it in gear, I can make the prop hub slip less than 1/4 of a turn. The prop had some minor damage when I got the boat so I suppose it's possible that one or more fins are bent enough to throw it out of whack. <br /><br />I know I probably shouldn't have, but I put a flush on it, cranked it, and had my wife put it in gear for just a few seconds, at idle, to see if the prop spun out of balance but it seemed OK.<br /><br />I noticed water coming from somewhere behind the motor supports that connect just above the lower unit, on both sides, & I can't remember if it did before or not. Is it supposed to?<br /><br />I checked the lower unit oil & it was fine.<br /><br />A river is where I learned boating from my dad as a kid. I picked up listening to the motor at that time, too. We had a late '60s Chrysler 70hp, I believe, and that thing with hum such a pretty note at WOT.<br /><br />Thanks, fellas, for your help!<br /><br />Catch ya later!<br />HH

 

[R.Johnson]

Re: I hit a dang log!

This is a hard call, as what may have happened to your engine. A water soaked log can do a lot of damage, and not even scratch the paint.Take a close look at your transom mounting bolts, and see if they are still tight. Disconnect the steering cable, and see if the the engine will pivot freely. See if the engine still sit's square on the transom. I once hit a floating log with my 125 on a Ckeckmate. The only thing holding it on the transom was the trim cylinders, and steering cable. The engine was sprung from top to bottom when I took it apart. That log was maybe 6-8 inch's in diameter. If your engine does not sound right, and is no longer tracking correctly you probably have some damage. It will take some close inspection to determine that. One thing that will suffer damage from high impact is the pinion gear, and that seems to always show up after it is to late. Impact is simply bad news to these larger engines.

 

[HappyHillbilly]

Re: I hit a dang log!

OK, I'll check those things out tomorrow (Sat) and if I find anything worth tellin' I'll report back.<br /><br />I checked the transom's strength to make sure it didn't give way but didn't think to check to see if the motor had shifted. <br /><br />This thing needs a new prop anyway so I'll get one the next week or so.<br /><br />Thanks!<br />HH

 

[Joe Reeves]

Re: I hit a dang log!

Water exiting at the lower motor mount area is normal. There are water relief holes there, designed to prevent water from traveling up the driveshaft tube.

 

[HappyHillbilly]

Re: I hit a dang log!

Ahhh, thanks Joe. <br /><br />Thanks!<br />HH

 

[HappyHillbilly]

Re: I hit a dang log!

Looks like the prop might be the culprit. After everything else seemed to be OK I decided to measure the distance between the prop's blades and the back of the lower unit. Two of the three blades were 3/16" further. I suppose these two got bent back rather than the one getting bent forward. Either way, the prop's out of whack.<br /><br />I'll get a new one the next week or so and post back to let ya'll know whether or not it was the culprit.<br /><br />Any prop brand recommendations? What's on here now is a 12 3/4 x 21 tri-blade, aluminum, unknown brand.<br /><br />Thanks, again, to all of you! I appreciate ya! <br /><br />HH

 

[geekomatic]

Re: I hit a dang log!

Another good argument for switching to a JET DRIVE.<br />I boat on a river as well (the Chattahoochee)and my ultimate goal is to have a nice jet drive outboard on the back of an aluminum flat bottom.<br />You just kinda "bounce" off all the stuff hiding under the water.In my case,it's HUGE rocks.

 

[HappyHillbilly]

Re: I hit a dang log!

I took the prop off & noticed rubber shavings from where the hub had spun. I put it back on & tightened it more than it was & tested it.<br /><br />The water churning and stressed sound was gone so I assume the hub either needed tightening or needs to be replaced. No, I didn't torque the hub nut, I don't have a torque wrench, yet. <br /><br />I'm still gonna get a new prop but I was wondering if all props' hubs can be replaced. Stamped on the rubber part of this prop's hub is: 389512 and 12 3/4 X 21. It looks like this hub can't be replaced, as if it's all one unit, but maybe they're pressed in/out.<br /><br />I've decided to get 2 aluminum props, with different pitches, one for fishing/boating and the other for skiing. Can someone please give me some insight on what brand to get?<br /><br />Is the cavitation plate supposed to ride above or below water surface when planed out? This is just above surface.<br /><br />This motor has a Doel-fin on it & I took it off to see if it made a difference in planing. Boy! Did it ever! It took about 3 - 4 times longer to plane out without the Doel-fin. A huge difference. <br /><br />geekomatic,<br />Your jet-drive argument is a good one. If I ever run across a boat w/ trolling motor/motor/trailer that is jet-propelled, for $400, which is what I paid for this setup, I'll jump on it, too. <br /><br />Thanks, folks!<br />HH