50 hp Merc

I just had lots of water in the oil in my lower unit, before I tear this apart can anyone tell me if this is a job for the shop or is it a do-it yourself job. The drain plugs are new also.

How old is the motor? When was the last time you changed the lower unit oil? When you did, did you replace the little plug seals or use the old ones?

I would try to get new seals and change the oil. Take it out for a good long run, come back and drain it again to check for water. If not, it was the seals, easy enough, just fill her back up and put new seals on. If not, a LU teardown can be a bit daunting if you haven’t done it before.

Just my 0.02 on this.

Just to reduce confusion, I belive D means the drain plug seal not the shaft seal(s) which might require a special tool for that one, depending on year, to remove the externally threaded nut holding the LU gear cace togther.

Have you removed the prop to check for line wrapped around the shaft? It can sometimes just make a gap and hindr the seal but most times it has not been found before the shaft seals are cut up.

Everyone should regularly remove the prop a few times a year to check for line, is quick and easy. good luck -Mark

Sorry, those were exactly the seals I meant. Just a quick test you can do yourself before deciding to take it in or get involved in a much bigger job. Most of my experience is on older OMCs, and I have learned to check the little things before jumping into a bigger job!

All the above advice is good, If it comes to it prop shaft seals are fairly easy. I’ve found merc seals are more expensive by a bit but worth it. Good Luck