Can I get an ASAP opinion??

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Pale_Horse_Idaho

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So my brand new yamaha F25 with only 40hrs has a heavily rusted woodruff impeller key. Do they not use stainless on the shaft and key?
I am guessing these keys are made of soft steel for a reason. Fresh water use only. If this was a salt water motor that key would have been corroded out.
Why so bad after only 40hrs fresh water?

My question:

Do I need to order a new key (2 flippin weeks to get a key out here)?
Do I wire brush im place and install new impeller?
Do I spray with penetrating oil let soak and then tap one side to rock key back and forth and fall out? Then wire brush key and slot and marine grease it and use it again?

*** The steel screws hold the pump on and lower on bolt into aluminum. They have some white dried hard stuff on them. Is that silicone or dried white grease? I'm thinking its some kind of sealant. What do I use? Dissimilar metals kind of protectant?

I do a new impeller every winter no mater how many hours.


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Based on your picture only, it appears to be just surface rust, very common. Depends on the water where the motor is used. Some have higher mineral content or acids that can speed up surface rust. In my 60 years of boating, I always wipe a film of water proof grease on the shaft and key to make them easier to remove down the road. I don't see any eroded material, just surface rust. A smear of good waterproof grease will make it easier next time. I see no reason not to use the existing key after it is cleaned up and coated with grease.
Others may see something I don't see.....
 
Based on your picture only, it appears to be just surface rust, very common. Depends on the water where the motor is used. Some have higher mineral content or acids that can speed up surface rust. In my 60 years of boating, I always wipe a film of water proof grease on the shaft and key to make them easier to remove down the road. I don't see any eroded material, just surface rust. A smear of good waterproof grease will make it easier next time. I see no reason not to use the existing key after it is cleaned up and coated with grease.
Others may see something I don't see.....
Rodger that and thank you!
I just wire brushed it and it cleaned up great. Do I use silicone on the mounting bolts? Mine have a dried white substance that looks like it might have been some marine sealer like white silicone.

What would happen if the impeller fins were put in the opposite direction? By accident of course.
 
I never use silicone as it typically has a shorter life and then nothing else will stick there.. Never saw any sealant used on impeller housings in all my motors, but never owned a Yamaha so they could be different.. I always made sure my impellors were in correctly, so I can't say there. That white substance might be mineral deposits from the water. I have a well and see mineral deposit like that often around my fixtures. Water pumps are a common replacement item, being out in the country, you might consider having extra parts on hand so you have them when needed. I always keep extra stuff like that on hand, even though I am not far from a marina, I like having what I need on hand...piece of mind I guess...
 
I never use silicone as it typically has a shorter life and then nothing else will stick there.. Never saw any sealant used on impeller housings in all my motors, but never owned a Yamaha so they could be different.. I always made sure my impellors were in correctly, so I can't say there. That white substance might be mineral deposits from the water. I have a well and see mineral deposit like that often around my fixtures. Water pumps are a common replacement item, being out in the country, you might consider having extra parts on hand so you have them when needed. I always keep extra stuff like that on hand, even though I am not far from a marina, I like having what I need on hand...piece of mind I guess...
Its not minerals. It seems like a white flexible sealant. You can scrape it with a fingernail. Its on all 8 bolts of lower unit and pump.
 
Put a Thread sealant paste on the threads for reassembly. Loctite makes a good one for example. Great stuff for any thread below the waterline.
100% Same thing the mech. at Napa just said. He was a mech. for 30 years before going to napa. He said they use it on small block intake manifolds to keep oil from migrating where it shouldnt.

There are 2 types he said. A water based (NEGATIVE) and a chemical based. The chem based is the one you want. A simple smell test will tell you.
 

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Why are half your impeller fingers backwards?
I change mine every 25 or 30 years lol
SOB! Thats the way it came from the factory. Wow!
Its a brand new motor too. Should I contact yamaha and let them know and ask for an extended warranty or what?
 
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SOB! Thats the way it came from the factory. Wow!
Its a brand new motor too. Should I contact yamaha and let them know and ask for an extended warranty or what?
If local, I would take it or pics to the dealer...otherwise send pics and a formal note to the mfgr. File a warranty claim. Gotta document in case of a future issue.
 
SOB! Thats the way it came from the factory. Wow!
Its a brand new motor too. Should I contact yamaha and let them know and ask for an extended warranty or what?


On my current Honda and previous Merc what you see is very typical when removing the impeller housing from the shaft. The hole in the impeller housing/cup is slightly off center (eccentric?). You can see that in the pic below. Assuming Yamaha is similar, because of that, when the cup/impeller is removed it is easy for the impeller vanes to do what you show in your pic. When you install the impeller over the shaft keep them in the proper position.

Cup.jpg
 
SOB! Thats the way it came from the factory. Wow!
Its a brand new motor too. Should I contact yamaha and let them know and ask for an extended warranty or what?

As long as it was peeing good I don’t see an issue. I would definitely replace it since it has been stressed
The opposite way. I have never seen a 50/50 impeller so I don’t think that’s right lol.
BTW, I seriously have never replaced an impeller on any of my engines.
I would however touch base with pictures with the Yamaha dealer you are going to have work
done if poop hits the fan and corporate if necessary to CYA yourself.
 
Do that and, if needed, they might use your pic to show you installed the impeller incorrectly. :) Especially if you thought it was a manufacturer or factory assembly problem.
 
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Is the impeller made that way, for forward and reverse? It appears to be made by casting so I doubt they got it wrong. This is interesting to me as I know nothing about them.
NO. The engine only turns one way. The prop has gears to go in forward and reverse, but not the driveshaft that turns the impeller.

Every service manual I have ever seen says to rotate the driveshaft while installing the impeller so that the vanes all turn the same way. Hard to believe the factory didn't follow it's own advice. Maybe a new guy was working that day and didn't know better.
 
Why are half your impeller fingers backwards?
I change mine every 25 or 30 years lol
Why do you think it is backwards? From the view in the pic the impeller would be turning CCW to get those bends. The view we have is the BOTTOM so from the top that shaft would have to be turning clockwise, which is correct.
 

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