Lower unit fluid milky

[muddinmann67]

Ok guys I have recently changed the lower unit oil in my 1990 70hp johnson and it was milky I guess you would say so I changed it again a few weeks later and it was the same, what is the norm for used lower unit fluid to look like once it's used for a while? I put about a pint of the lower unit fluid in a mason jar to see if any water settles on the bottum, it's been setting for about 8 hours with no change in fluid and no water settling.....

Need your guys's input on the situation, do I need to replace seals or no?

 

[jimmbo]

The oil should look the same when you drain as it did when you put it in. Milky means water-oil emulsion. Water cooled gears are not good. You have a leaky seal. Might just be the gaskets on the fill/drain plugs, or the seals under the water pump are allowing water under pressure into the gearcase and forcing oil out the propshaft seal or shiftshaft seal. Perhaps fishing line wrapped around propshaft and damaged the seal. Get the gearcase pressure and vacuum tested

 

[64osby]

Change it one more time with new crush washers on the plug screws. If is leaks again rebuild all the seals. My .05.