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Lower Unit Stuck, No Movement At All...

H

haydenfox

Member
I mean I'm getting no separation at all. Advice? I've tried to hammer it and started it with bolts slightly attached to catch it. There isn't even room for wedges.
 
As far as using chisels, wedges, etc. Wouldn't that cause the aluminum on the L/U to bend away from the housing? It looks like the previous owner may have done this before because there are what looks like little screwdriver pricks where the L/U and housing meet. I've noticed water coming out of them before while flushing but just thought it was normal seepage.

I ask mainly because if the splines are seized the motor is basically trash, although usable for now. Is it ok to crease the L/U if I try to pry/wedge it apart, or will that factor into whatever life the engine has left?
 
There are a number of things you can try before calling quits on the motor.Hang it upside down pouring plenty of PB blaster I think it's called in the 'States,let it hang for a few days.Drill a hole up at the top of the leg for access. Flip it back and have a couple of shots at starting,without the bolts or nuts tight,it may rattle lose.
It won't really look great but will be usable unless you crack the lower unit or break a water pump housing.
The fact that you have no gap at all makes me lean more towards the dowels,apply heat where they are located,have a look at the diagram,give it another go.Usually the crank shaft will give you 1/8"
I have no idea what it would cost to have a shop look at for you but I would guess a lot.But depending on the condition of the impeller,and judging by what you are saying,it hasn't been changed in quite a few years so when it goes,over heat and sudden sharp stop,sooner rather than later
 
haventaclue said:
There are a number of things you can try before calling quits on the motor.Hang it upside down pouring plenty of PB blaster I think it's called in the 'States,let it hang for a few days.Drill a hole up at the top of the leg for access. Flip it back and have a couple of shots at starting,without the bolts or nuts tight,it may rattle lose.
It won't really look great but will be usable unless you crack the lower unit or break a water pump housing.
The fact that you have no gap at all makes me lean more towards the dowels,apply heat where they are located,have a look at the diagram,give it another go.Usually the crank shaft will give you 1/8"
I have no idea what it would cost to have a shop look at for you but I would guess a lot.But depending on the condition of the impeller,and judging by what you are saying,it hasn't been changed in quite a few years so when it goes,over heat and sudden sharp stop,sooner rather than later
Click to expand...

Stupid question I know, but how do I hang it upside down? Also, if Im applying heat, where do I heat and with what ? Is one of those propane torches enough?
 
I have used an adapter on the crankshaft thread, and a hole drilled in the lower unit skeg. ----Then a hydraulic puller to seperate them.----------Not impossible to do if you know how it all works.
 
racerone said:
I have used an adapter on the crankshaft thread, and a hole drilled in the lower unit skeg. ----Then a hydraulic puller to seperate them.----------Not impossible to do if you know how it all works.
Click to expand...

I don't have access to crankshaft. I'm still getting no separation. I've been trying to figure out a way to use a hydraulic spreader , porto-power, etc. But like you said, I do not know how it all works....
 
racerone said:
????----The driveshaft may be stuck in the bottom of the crankshaft !
Click to expand...

I'm new to this, therefore there is a certain vagueness in your responses. Although I do greatly appreciate the help. Ok, so I remove the flywheel and connect an adapter, which I assume is a nut? Then what? Turn it with ratchet or drill? Which way is it safe to turn? Can I use an impact drill? I do not understand the puller suggestion at all. TIA
 
What racerone is saying is drill a hole in the skeg,the thin flat bit on the bottom of the outboard,to anchor it,and attach the adaptor,a threaded eye which screws to the top of the crankshaft. Something like this,BUT not this, http://www.ebay.com/itm/Mercury-Mar..._Accessories_Gear&hash=item3f383b7622&vxp=mtr .The threads are on the inside,like a nut,and screws directly on to the crankshaft.The tool in this link attaches to the flywheel to either lift the motor or pull the flywheel.
So,drill hole in skeg,anchor to something substantial with heavy duty chain,attach adapter hook on something like this, http://www.innovation-engineering.co.uk/h8p.htm ,also attached to something substantial.
Proceed with hydraulic winch to try and separate the drive shaft,which fits into the bottom of the crankshaft.
 
haventaclue said:
What racerone is saying is drill a hole in the skeg,the thin flat bit on the bottom of the outboard,to anchor it,and attach the adaptor,a threaded eye which screws to the top of the crankshaft. Something like this,BUT not this, http://www.ebay.com/itm/Mercury-Mar..._Accessories_Gear&hash=item3f383b7622&vxp=mtr .The threads are on the inside,like a nut,and screws directly on to the crankshaft.The tool in this link attaches to the flywheel to either lift the motor or pull the flywheel.
So,drill hole in skeg,anchor to something substantial with heavy duty chain,attach adapter hook on something like this, http://www.innovation-engineering.co.uk/h8p.htm ,also attached to something substantial.
Proceed with hydraulic winch to try and separate the drive shaft,which fits into the bottom of the crankshaft.
Click to expand...

Perfect! Thank you
 
Did you ever try cutting a hole at the top of the leg and applying heat directly to the drive shaft near where the shaft and crank meet? The hole can be repaired easily with epoxy filler.
 
I have a 9.8 hp Merc power head out back with the remains of a driveshaft still stuck in the crankshaft. Tried an acetylene torch and a bunch of other things--no good. That sucker might as well be welded in there!

Yours might be the same. Since that power head is very valuable, cutting the driveshaft off and removing the PH might be worthwhile (assuming the stub can finally be removed). The driveshaft housing and LU are of much lesser value.

Jeff
 
fastjeff said:
I have a 9.8 hp Merc power head out back with the remains of a driveshaft still stuck in the crankshaft. Tried an acetylene torch and a bunch of other things--no good. That sucker might as well be welded in there!

Yours might be the same. Since that power head is very valuable, cutting the driveshaft off and removing the PH might be worthwhile (assuming the stub can finally be removed). The driveshaft housing and LU are of much lesser value.

Jeff
Click to expand...

Thanks that may have to be a last resort, iv also here'd that heating the area were the locating dowels may be worth a try, also running the engine while bolts loose on lower unit,

but bit worried about trying that incase it damages the drive shaft splines ?

Cant my believe this is such a common fault with this motor! Shame as power head in really good condition !
 
..."...bit worried about trying that incase it damages the drive shaft splines ? "

So what? You're not likely to save the LU in any case. Salt water and a lack of lube during assembly causes ALL kinds of problems. Personally, I won't work on any more salt water specials (unless I charge double!)

Jeff
 
fastjeff said:
..."...bit worried about trying that incase it damages the drive shaft splines ? "

So what? You're not likely to save the LU in any case. Salt water and a lack of lube during assembly causes ALL kinds of problems. Personally, I won't work on any more salt water specials (unless I charge double!)

Jeff
Click to expand...

I see you point Jeff,

So got home and tried running the engine and noticed with the muffs on water comes out from were the anoids are and out of the splined hole were the gear link rod enters the gear casing, also from a little hole near the right rear mount bolt ~?

Is that normal to see water coming out from all these places not just the tell tail ?

If so i can see why things get siezed up :(
 
..."Is that normal to see water coming out from all these places not just the tell tail

More or less. Water comes out all kinds of places with the motor on muffs.

Jeff
 
You can try this as it works on sterndrives, take boat to ramp and back in and trim down so skeg is a couple of inches off bottom of ramp. Install a old aluminum prop with 2 ears bent/damaged. Start motor and put in gear and run till it vibarates off but be ready to pull kill tether. If water pump is not working you can use a bilge pump and hose to pump lake water thru engine thru flush port. I have removed several drives this way....
 
fastjeff said:
Agreed. Leave the nuts just barely on.

Jeff
Click to expand...


Ok that sounds extreme but i see how it might work!

Thanks for all your ideas,

I have to admit for what was supposed to be a five min job im now in two minds if to carry on trying to pull the motor now are wait till end of season,

Although i have no idea if the water pump is top notch as only just bought the boat but it does pump well out of the tell tail on muffs !

mmm maybe a engine temp gauge instead to get me through

Thanks again
 
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