I want to take a shotgun to my outboard

[Merc90HPnewbie]

I pulled out all the bolts and nuts that hold the lower unit on and the ^(*&@$# thing won't drop down. I put it in forward as the book says (tried neutral too in case the book was wrong again). I pulled the prop off just for the heck of it, I was thinking maybe there was a hidden fastener or I could peek in and see something. No dice. The prop did come off nice and easy so someone did the right thing at least with the prop.<br /><br />The boat ran a week ago so the drive shaft isn't rusted and fused to the running gear... (When I did a search on 'lower unit stuck' that was the most common post I found)<br /><br />What am I missing here(aside from weekends on the water ?!?!?!<br /><br />P.S. - two things. 1) I don't think there is a shift linkage on this motor to worry about. There was nothing in the book and I didn't see anything obvious up by the powerhead. 2)After removing one bolt and three nuts, and loosening two more nuts, there is a very very very small crack, about 1/64" or less all around... enough to make me think there's one thing yet holding it on. BUT there's no mechanical wiggle that I can feel nor can I seem to push the lower up to close the gap. It just isn't acting the way I would expect. However this is my first time doing this so I wouldn't know The shifter now wont go into reverse smoothly. Is this a clue?<br />Thanks for any help you can provide

 

[Xcusme]

Re: I want to take a shotgun to my outboard

Don't load the 12 gauge just yet.....<br /><br />The drive shaft would have a hard time rusting in the lower unit, it's sitting in 90 weight oil. The other posters are talking about the drive shaft rusting in the crank shank splines in the power head ( at the other end of the drive shaft) . Be sure your shift linkage is disconnected per the manual and try again. You could have a rust/binding issue with the drive shaft after all. If the shaft is rusted, lots of penetrating oil and even more patience usually wins the day.

 

[Merc90HPnewbie]

Re: I want to take a shotgun to my outboard

I didnt see anything in the manual about shift linkages. I just looked again now. In fact there's just one mention of (shift cable alignment) but nothing about a linkage. The chapter on dropping the lower unit just says to put it in forward and it shold drop. I see your point about the shaft rusting at the other end. From what I saw earlier today, there's a cable that pulls on a lever attached to a rod that goes down from the bottom of the power head. It doesn't look like something to disconnect but I could try it... I am at my wits end anyway <br /><br />Thanks

 

[alcan]

Re: I want to take a shotgun to my outboard

Hi merc<br />Take a pill, calm down. Sit down in the den and re-read your manual. Trust me these books are not ever wrong. They will tell you how the job is supposed to go step by step. After a calm, through re-reading, check, then double check to make sure you got all the fasteners out. Did you get the one under the trim tab? I will assume you have a 90hp Merc. please post your ser# so we can look up info for you. Once you have determined that you infact have all the bolts out we can direct you farther.

 

[Merc90HPnewbie]

Re: I want to take a shotgun to my outboard

Hi!<br />I have been trying to get the thing off for 2 weeks already, I took plenty of breaks to cool down!! <br /><br />It's an 1985 90 HP mercury 6 cyl L head SN 6624434.<br /><br />I reread the book several times, even had the wife look at it for a different perspective. In fact it is already provably wrong in at least one section. They do not mention the nut at the front (on the stud pointing up) and they call the two nuts up in the middle of the anti ventilation plate 'one nut'. That's two strikes against the Seloc book It's a pretty stupid mistake because in the picture showing the bolt under the trim tab you can atually see that there's two nuts under the antivntilation plate. It's no huge deal but it makes me lose confidence in the manual's accuracy. I did get the one under the trim tab. The other one commonly missed is all the way forward, pointing up. I removed a total of one bolt and five nuts.<br />Thanks

 

[dvchristoff]

Re: I want to take a shotgun to my outboard

Merc,<br /><br />If you do not have power trim on this motor you probably have a reverse lock shaft that I think needs to be disconnected before the lower unit will drop. Just a shot in the dark.

 

[Merc90HPnewbie]

Re: I want to take a shotgun to my outboard

macasylum: Thanks for the reply. I scoured the book for references to a shift linkage or something else that would need to be disconnected up top but there's nothing. From other posts I've read on the board, the shift shaft is splined and the lower unit should just fall out on this engine. PS I *do* have power trim on this motor- does that mean I should be doing something else?<br /><br />Thanks!

 

[Chinewalker]

Re: I want to take a shotgun to my outboard

Hi Merc,<br /> Find yourself some of those wooden wedges they use to shim door/window frames. Use them to put some pry-pressure between the lower unit housing and the exhaust housing. You've got all the connectors - don't worry about that any more (you've got enough to worry about!!!) The shift shaft is a slide-fit - all splines, nothing to disconnect.<br /> If the lower unit hasn't been off in a long while one of four things is likely holding it...<br /> - Driveshaft - stuck/rusted into crankshaft. The driveshaft is stainless steel, but the crankshaft is not. If it wasn't greased properly last time it was apart, it's possible the splines in the crank have worn/rusted and are wedged into the driveshaft splines. Try placing a block of wood between the prop and cavitation plate and turn the flywheel backwards - might free up the splines if they're wedged in place.<br /> - Water tube - it's copper and can sometimes become glued/stuck into the rubber grommet in the top of the pump housing. Gentle persuasion can free it up.<br /> - Shift rod - may have rusted into the coupling if improperly greased last time out.<br /> - Exhaust tuner - may have become stuck in the rubber gasket where it seats in the lower unit. <br /> Get yourself some PB-Blaster, CRC, Kroil or what-have-you and start spraying inside the housing. If the rubber parts have fused to the metal parts (water/exhaust tubes) it may loosen things up. If the driveshaft is stuck, you'll have to upend the motor and start spraying down the driveshaft. Same for shift rod...<br />- Scott

 

[SeaHorse]

Re: I want to take a shotgun to my outboard

If you decide on the shotgun approach be sure to get some pictures for us. This will be a classic!

 

[Merc90HPnewbie]

Re: I want to take a shotgun to my outboard

haha!<br /><br />Ok, good advice from Chinewalker. I will try that tonight. Since the crack is so small, I don't know what I could put in there that would give me much levering power. I would try a screwdriver but I know that would just bend up the housings. Maybe i can find some wide sheet metal to use.<br /><br />Where should I spray the lubricant? In the exhaust overflow holes (two square holes at the top of the midsection)?<br /><br />P.S. in the book and in one post I read here they specifically say NOT to lube the top of the driveshaft... I think the reason is it will push the shaft down slightly and cause it to mesh incorrectly with something (not sure if its up in the crankshaft or down in the lower unit)?<br /><br />PPS I think this motor is over 300 lbs... if this doesn't work I dont think I can manage flipping it over, it's gonna have to go to the shop :-(<br /><br />Thanks!

 

[Kenny Bush]

Re: I want to take a shotgun to my outboard

Do it...... Shoot it.... It will come off. Show it who's boss. Darn'd old black anchor.

 

[Merc90HPnewbie]

Re: I want to take a shotgun to my outboard

haha! I think tonight I will bring the 12 ga out with the tool box... get that mercury shaking in it's boots....

 

[paulgp6022]

Re: I want to take a shotgun to my outboard

Drop it off a cliff, it will come off!

 

[vista4u2]

Re: I want to take a shotgun to my outboard

Though i am no expert, I too had much trouble getting the lower unit off my 84' 6 cyl 115 Mariner. It wasn't till I got out a good size rubber mallet and hit downward all around lower unit gear area before mine budged. Upon inspection afterwards, it seemed mine was binded up mostly around the exhaust tuner. That's right - get a bigger hammer, just make sure it's rubber, and then still try to show a little restaint.

 

[BF]

Re: I want to take a shotgun to my outboard

If I read you right, you said you took off 1 bolt and 5 nuts. In order to loosen L.U. you have to take off 5 nuts (usually with 5 washers), trim tab and its retaining bolt, and the bolt that is underneigth the spot where the trim tab was. <br /><br />That makes 5 nuts, 2 bolts and a trim tab. You might want to check whether you REALLY took off the one under the tab.<br /><br />Brent

 

[Merc90HPnewbie]

Re: I want to take a shotgun to my outboard

Oh I see, yes I wasn't counting the bolt that was actually holding the trim tab on... You are right, if I looked down at the ground after doing this there would be two bolts, one trim tab, and five nuts with washers. (And a 00 buck 12ga shell )

 

[Merc90HPnewbie]

Re: I want to take a shotgun to my outboard

Vista4u2: I am having trouble finding a suitable surface to hammer on. There's no good horizontal places to hit it aside from taking the prop off and hammering downward on the prop shaft. Do I have to worry about hitting it off axis and bending something or breaking an oil seal or bearing somewhere?

 

[Kenny Bush]

Re: I want to take a shotgun to my outboard

Take a chisel or wedge and tap to seperate. I like using a wood chisel(flat on 1 side). I would tap a few times on the front, then a few times on rear, and keep alternating...... After the shotgun blast, use a cutting torch.

 

[vista4u2]

Re: I want to take a shotgun to my outboard

I don't recommend hitting in the prop shaft area. I pounded downward on the round tubular area that houses the gears, if you know what I mean. I know it's not a horizontal surface, but there is enough lip there for the hammer to get good bite.

 

[vista4u2]

Re: I want to take a shotgun to my outboard

I don't recommend hitting in the prop shaft area. I pounded downward on the round tubular area that houses the gears, if you know what I mean. I know it's not a horizontal surface, but there is enough lip there for the hammer to get good bite.