1988 Merc 45 hp inline upper and lower bearings

[MercNub]

How and what tool should I use to remove the upper and lower bearings to get access to the upper and lower bearing seals. The manual has a part number for a bearing puller, but I can not locate one. Also this is going to be a bigger problem for the lower bearing seals as they are located underneath the bearing, so the bearing will have to be removed to gain access to them. The top one is visible and the manual says to use a chisel to bang it out. Thanks for your help.

I am pretty sure the upper bearing seal is leaking on my outboard as the trigger was soaked with fuel/oil mixture and all the wires and trigger where soft, swollen and broken. I did find one of the upper end cap bolts loose and re-torqued it back down, but I am not sure one loose bold could cause the kind of leak I found.

 

[Faztbullet]

Re: 1988 Merc 45 hp inline upper and lower bearings

You should not have to remove the bearings off crankshaft to replace seals. The endcaps are just a friction fit over bearings,just lightly tap and rock them off side to side. Most of the time a good straight tug will pull them off.

 

[MercNub]

Re: 1988 Merc 45 hp inline upper and lower bearings

For the later eighties 45 / 50 engines you are right the lower seal is visible. I have another power head from 1980 and the lower end cap is pointed or extended. I think on this type of end cap you might have to remove the lower bearing to gain access to the seals. I haven't taken the 1980 power head apart yet since I want to compression test it first. The other power heads from 1984, 1985, and the 40 hp from 1992 all have the flush lower seal so it will be easy pop them out.

If you had to remove the lower bearing would you use a screw in press or just hammer it out with a bearing remover?

Thanks again for the help.

 

[CVX20SPRINT]

Re: 1988 Merc 45 hp inline upper and lower bearings

I think what Faztbullet is saying is that the brg's will stay on the crankshaft when you pull the cap off.The brg's are pressed onto the crank.

 

[MercNub]

Re: 1988 Merc 45 hp inline upper and lower bearings

I think the 1st owner of the power head I have used some loctite red to glue them in, because they are up in the end caps good.

The guy didn't do a good rebuild on it either since when I got it both piston 1 and piston 2 where rusted into the bore. I thought it must have been a cracked power head until I tried to get the cylinder cover off and found that every screw was rusted badly and the seal around spark plug 1 and spark plug 2 where bad. I think the cylinder cover plate is warped too. interestingly enough after I carefully removed the pistons, both cylinders look good and measure up within specs.

 

[Faztbullet]

Re: 1988 Merc 45 hp inline upper and lower bearings

If you have the crank out of engine, just tap the end caps off with rubber hammer. Use a bearing splitter and press to remove and install new bearings. You can mix and match end caps as long as they are for a ADI ignition system,just make sure when you reassemble that you measure crankshaft end play and shim correctly.