2005 f225TURD's

[99yam40]

the studs the nuts fit on are part of the problem,
corrosion has grabbed a hold of them.

I hate those things.

last resort, I usually thread the nuts back on flush with the top of studs and then wail away on them too to see if that helps any.
are the studs in the lower unit or in the middle housing
that will make a difference.
wailing on them if screwed into the middle housing may not do any good

[oldmako69]

6 nuts. 2 bolts.

The studs are in the center section. The bolts come up from below. I think there's enough room for me to get a second bolt on and wind them out. Will try this. And a much bigger hammer.

There is no corrosion evident on the studs. I'll get some Aerokroil on them and try and back them out.

[panasonic]

I am with Yam40 on this. If you have no gap whatsoever after all fasteners are out and some hammer love, then corrosion around the studs probably got it held tight.

Do you see any evidence of corrosion where the studs pass through the case?

LU should drop slightly if it is only being held by the driveshaft seized in the power head.

[99yam40]

seems like I remember Rodbolt mentioning that normal corrosion eater oils do not work on aluminum corrosion.
he said he used a solution with bleach .
but never saw him write exactly what it was

[99yam40]

6 nuts. 2 bolts.

The studs are in the center section. The bolts come up from below. I think there's enough room for me to get a second bolt on and wind them out. Will try this. And a much bigger hammer.

There is no corrosion evident on the studs. I'll get some Aerokroil on them and try and back them out.

looks to me the words bolts should have been nuts

[oldmako69]

You are correct. The NUTS come up from below onto the STUDS. I think there's enough room for me to get a second NUT on the effing corroded all to hell STUD and wind them out. I have a LOVE/HATE relationship with these engines. I had a great summer, prob put on 100 hours with zero issues. Oh well.........

On the road for a week. I'll try to pull the studs next and then bang from there. I cannot imagine enough corrosion on the shaft splines to hold these heavy gearcases this tight. I think the anti-corrosion paint on the parts failed and that the things have cemented themselves together. What type of paint or coating can I replace the YAM fact paint with when I finally get them apart?

[panasonic]

They certainly do get stuck with the driveshaft spline corrosion....sometimes they have to be cut off.

I would be very careful about trying to wind those studs out. They are in there tight. I am not sure if they put thread locker on them from the factory or not. I'd put some heat to them before trying. Last thing you need is broken off studs.

[pstephens46]

They certainly do get stuck with the driveshaft spline corrosion....sometimes they have to be cut off.

I would be very careful about trying to wind those studs out. They are in there tight. I am not sure if they put thread locker on them from the factory or not. I'd put some heat to them before trying. Last thing you need is broken off studs.

I think you are right on the studs potential to shear. At least try the running at ramp option first.

[marchmadness]

first things first doesn't it seem odd that both motors lower units are frozen. But anyway the nuts and studs are not what you call a tight tolerance. So not getting it to drop at all would leave me to believe its frozen into the block. I would let the motors hang verticle and spray as much wd40 I could any where it could work in . Hang some type of weights on the lower unit trying to use gravity. Use a dead blow hammer and start working it . Also you can try heat on the studs if you still thinks its corrosion.

[oldmako69]

OK. Got em off. The right mallet did the trick.

Both woodruff keys were a monumental PITA. Fortunately, I just bought a pneumatic hammer and that sumbitch paid for itself on its first job out of the box. Ingersoll Rand. 40 bucks on AMZN. I was getting nowhere with a simple hammer and chisel.

Question - Any thoughts to taking some emery cloth to the new key prior to insertion? I will for sure use A-seize on it. My thought is that almost nothing is going to move that key once it's in place. It's under a bit of load when the engine is running and that load is 90 degrees to the slot. So, if it were an RCH thinner I might not have to get cro-mag next time.

Problem - One engine is full of emulsified oil and I am unsure where the leak might be. The drive shaft bearing carrier is not fouled with emulsified oil, but the keeper spring is busted. Both engines' springs are broken in fact, so I am off for new springs. The shaft seal on the leaky engines doesn't look horrid, but I am going to replace it anyway as well as the O ring immediately below it.

Question - How tough is it to replace the prop bearing? I'm tempted to replace the drive shaft bearing seal, add new gear oil and run the boat a few times and then sample it. If the gear oil is emulsified again, then I'll go after the prop seal.

Question - What's the best way to remove the drive shafts upper bearing carrier seal? Bang it out from below?

[fairdeal]

The key can absolutely be ground down to a 'loose fit' -
allowing it to be 'swimming in grease' -
the only caveat, then, when sliding the impeller on,
don't push the key out ahead of it.

I'm not following the "I am off for new springs" ?
if you mean the 'garter spring' of the shaft seal -
by now you have found that is not a separate part...

To replace the driveshaft seals (two, stacked) -
you should be able to remove the bearing carrier without too much fuss
(although there was a recent thread here about a nightmare removal).

Replacing the propshaft seals is another thing altogether;
although 'the right way' is to remove that bearing carrier,
IMO, its not worth the battle or the expense of the tools
(slide hammer puller, oxyacetylene torch)

It is far faster and easier to use the "hack method"
although that requires extreme care and finesse,
to assure that the shaft surface is not scratched.

Some would advise replacing all the seals 'while you are at it'
driveshaft, propshaft, shiftshaft.

but you could instead start with a pressure test
and some soapy water to reveal the leak -
and let the others slide.

You are going to want to pressure test the units anyway,
before you put them back in service;
so you'll need to McGuyver a rig for that.

[oldmako69]

Thanks for all that.

I'll likely try and thin those keys a micron.

Off for new springs meant new driveshaft bushings and O rings below the water pump. I found that tapping the sides of the "plate" with a drift and a mallet it loosened it radially and made it much easier to remove.

I don't plan on messing with the prop shaft seals. I'll fix this and do a PSI check. If still leaking I'll cart them over the YAM guy. They're in my garage now, so it will be an easier matter to just let him change them out. Just watched a YouTube vid that dissuaded me from trying that job without the proper tools.

Off for parts.

[TownsendsFJR1300]

Plus one on pressure testing.. Address what IS leaking..

If that lower prop seal isn't leaking, I wouldn't open that can of worms.

Also, I strongly recommend using Yamaha's waterproof grease for the mid section bushing.. (Or similar OMC, etc grease)
Using regular (non marine) grease on that bearing WILL squeak down the road-Been there, done that.. I don't like "do overs"..

[panasonic]

Oldmako would you care to elaborate on how you got the LU off? Do you have to use wedges or just a bigger hammer?

[99yam40]

Oldmako would you care to elaborate on how you got the LU off? Do you have to use wedges or just a bigger hammer?

he wrote using the proper mallet and then whacking from the side also from what I read.

or maybe he was talking about something else here"

I found that tapping the sides of the "plate" with a drift and a mallet it loosened it radially and made it much easier to remove.

"