Prop blade go bye-bye?

JC42

New Member
My pops was heading out in the straights today when he said the engine suddenly started making a horrible noise, said he shut it off right away and eventually found an entire blade of the prop was missing. I’ve never seen or heard of this happening, but I’m more concerned about the rest of the lower unit.

-will the ~5 seconds running two blades wreck the bearings in the lower unit?
-we have a spare prop that appears to be used (got it with the purchase of the boat a few years back) is it a good idea to use?
-any prop recommendations for us? Boat is a trophy 1802, 135hp merc 2stroke about 3400 lbs ready to fish
 
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Try the other prop. You will find out quite quickly if there’s any damage to the shaft and/or gears. I hit a rock and bent my stainless prop, put my spare alum. Prop on and all was good.
 
Where is the rest of the skeg? Had to have hit something pretty dam big or hard or both. You would think you would feel it.
 
Where is the rest of the skeg? Had to have hit something pretty dam big or hard or both. You would think you would feel it.

skag looks the same as far as I’ve seen. I don’t think they hit anything. I betcha there was a hairline crack prior to this that went unnoticed but I’m not sure
 
Well it sure looks like part of that skeg is missing. The taper stops too soon. He hit something either just before it snapped off or there was a hairline crack. have a look at the fracture point. You can often tell if there was a hairline crack. The metal will look different then the part where it actually separated.
 
I wonder if that's maybe just the angle of the photograph? It looks like that to me too but you can see the rounded lower forward edge so now I'm thinking maybe it's just on an angle where it appears really shortened.

My guess is that a few seconds of run time won't kill the lower but I wouldn't be too surprised if the shaft has a bit of wobble to it now...but they can be straightened pretty easily. If you have the ability to check shaft runout I would.
 
The angle of the picture is a little deceiving, the skeg is all there although there are some new scuffs, presumably from a blade flying off. After a closer look, I think there was old damage and 'x' amount of time and corrosion sent it out. I'll attach some pics for you all to look at as I could be wrong. Any resident prop-experts here have any tips for a replacement? reputable brands? Probably going to go stainless for our next one.

Edit***Current prop is 14.25 x 21P -- Mercury website suggests ~15 x 17/18/19P
Also, 3 or 4 blades for the next prop?
 
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Where is the rest of the skeg? Had to have hit something pretty dam big or hard or both. You would think you would feel it.

Ya looking like a good bit of the skeg is missing...? wow
 
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Ill be honest go spend the bucks and go get a brand new one take the spare in to be "retuned" to a prop guy looks that prop has seen better days anyways Solas makes some nice SS ones as well little bit more but worth it
 
Ya, I only keep an aluminum as a spare on the boat in case. Once you've gone SS you'll feel the diff right away.
 
There is nothing wrong with your skeg, I'll bet nothing wrong with your lower unit either. Put on a new prop and you'll be fine.
 
That prop sure looks like it has been suffering from corrosion, which may explain what happened. Is there corrosion elsewhere near the transom? You may have more than just a prop issue.
 
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Ya, I only keep an aluminum as a spare on the boat in case. Once you've gone SS you'll feel the diff right away.
I apologize for the hijack, but... I need to get a second prop for next season & I’m debating about going to SS. What is the difference “you’ll feel right away”? I don’t mind spending the extra if the performance improvement is really noticeable.
(The boat already performs nicely with the stock prop from Suzuki.)
 
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I apologize for the hijack, but... I need to get a second prop for next season & I’m debating about going to SS. What is the difference “you’ll feel right away”? I don’t mind spending the extra if the performance improvement is really noticeable.
(The boat already performs nicely with the stock prop from Suzuki.)
Better hole shot. Higher top end rpm/speed. SS doesn’t flex under strain. They’re stronger and generally thinner in design causing less hydrodynamic disturbance.
 
You need to decide how ''poor'' your craft performes with an aluminum prop....do you NEED a better hole shot and do you need more top end. / rpm.
compare a new S.S. prop to an aluminum prop ''cost wise''. as i often say,being on pension, i count my$$$$$$$$$.
AND i don't worry too much about my prop being ''borrowed'' while i'm having lunch at a restaurant.....when you see boats over in UKEE or PORT without props on at hotels,marinas you can bet the ''captains ''pulled those S.S props and ''hid '' them for the night...
just saying, deep pockets-no proplem. just something to think about.....
p.s. hit something hard with s.s. and you could damage more than the prop,. aluminum, well they break and are cheap......
aluminum props are like FORD-F150 Or DODGE Ram 1500 pickups.....not very spectular but they work just fine.....
just in defence of the lowley ,aluminum wheel !!!!!;)
 
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When you need a new prop by I may have one kicking around in my mess of a shop of my 1q5 hp mercury of my trophy. But I’m up moose hunting now. I can look if not in a hurry, I’m in Ladner when home
 
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