lower unit seals

[spacecwboy]

finally got my motor running in a barrel out back and after running for a few minutes I stopped it and checked the lower unit oil. it is taking in water somewhere so I am going to replace the seals. is this a DIY job or should I pull the lower and take it to the shop? It is about a 74 model Merc 20hp. Model 200. Any ideas?

 

[Motor Boater Bill]

Re: lower unit seals

It can be a DIY if you're up to it--you'll need a manual and a special tool to pull the propshaft bearing carrier retaining nut, which can be fabricated. As a first step, you can pull the LU, put 10-15 psi in it, submerge it an look for bubbles. The drive shaft seal and shift shaft seal are easier to replace. However, be advised that you my not have a stainless steel drive shaft so look out for corrosion under the water pump that can eat seals. If so, you'll need to deal with that.

 

[Texasmark]

Re: lower unit seals

Hey Bill, I'll never forget the first time I saw a salt water Merc drive shaft before they went as OMC did years earlier, to a SS drive shaft. This was back in '65 ish time frame so the engine was like a '62. Couldn't believe they had been doing that. Don't know whey they came to their senses.<br /><br />Mark