Trying to remove lower unit on merc 25HP

[Paul Welc]

Does anyone know how many bolts I need to remove lower unit to change water impeller? I have removed the 4 bolts holding the lower unit and one on the back but it doesn't want to come free. It is a mercury 25 HP 4-stroke Bigfoot.

 

[ND Bass]

Paul, hold up until one of these guys replies with thorough instructions but....I think you need to have it in gear before you remove it so things line up when you're putting back together.

 

[Paul Welc]

Thanks NDBass it looks like linkage from the lower end (small bar) goes up to the shift linkage on top where it shifts. I asked the guy were I bought the impeller kit and he said it won't matter about having it in gear as you have to remove the shift linkage. I have removed the cotter pin that goes from the carb to the shift linkage but there must be some trick I'm missing as it is not coming out of the front of the motor when I push it forward...

 

[Paul Welc]

NDbass I see on youtube were a guys has same issue "removing the lower unit and shift shaft coupler" but I can't figure out how to get to the shift shaft coupler...



http://www.youtube.com/watch?v=46RryAt1smY

 

[Bruce Freeman]

On my 150 there is a bolt hidden under the trim tab?



BF

 

[Mike Newman]

I just did mine for the first time this past spring. There is a 5th bolt hidden under the trim tab. Mark the position of the tab prior to removing. Also you must be in neutral prior to starting. First thing is to disconnect the gear shift linkage. You will find it on the front of the motor just above the lower main cowling. There is an overcam clip that you flip back and then slide to the driver side to dis-engage the shift linkage. if you do not do this you can do serious damage if you try and drop the lower unit which is connected to the other end. I had my wife come out and help pull it off and also to re-install later. You have to fish that linkage all the way back up into the housing and re-attached to linkage at top. This is the hardest part of the job.

 

[Berry Lindley]

I don't know if the 25 linkage requires neutral, but on the 90 is is recommended that you be in gear when droping the LU. If all the bolts are out, you may have to shake, bump, etc it free.....Do not overtighten the hardware on the impeller, and put some Merc lube on the impeller and gears.