milky lower unit oil

[digong]

Hi, I bought my boat couple of months ago with a 1975 50 hp evinrude, when drain and replace the LU oil, it looks old and dirty like black color and no sign of water as far as i can remember, replace the gear oil and also cleaned the prop, after several times running the engine (connecting flapper and water hose) not on the lake, checked the oil and now looks milky, any idea why? have read some comments that the two (drain and fill screws) should have washer on it, i did not see a washer, is it possible that i did not put back the prop properly?, appreciate your comments in advance.

 

[Crosbyman]

the washers could be stuck use a pick to nudge them out … in any event washer or not you need to put new ones in.


look for mono line around the prop shaft near the shaft seal

if after you install new washers and do a run or two and find contamination on the next inspection you will have no other options but to reseal the gearcase ...or change the oil a few times during the summer season

if you run it all year long well….reseal the gearcase

 

[racerone]

Yes there should be a washer at each screw.-----Often the washer stays in place.-----One of those check twice work situations..

 

[digong]

Appreciate the suggestion guys, I will do those things and report back, thank you.

 

[jakedaawg]

If it got milky while only running on the hose then I would suspect the seal on the vertical shaft under the water pump

 

[Mohawkmtrs]

Don't guess...perform a pressure test on the gearcase.

 

[boobie]

And vacuum test.

 

[digong]

How to perform vacuum test and pressure test, what tools do i need to have to complete the work. Still waiting for new plug and washers to come then can fill the gear oil and run the motor, thereafter i can provide feedback on the result.

 

[boobie]

Take the motor into a dlr and have him do the P&V tests if you don't have the tools.

 

[digong]

Thank you, will do that after couple of runs, the washers came yesterday and i have replaced the leg oil put the washers and a teflon on the plugs.

 

[digong]

After running several times with the new nut and washers, oil looks clean and no sign of water, finally weather was goid and lakes are opening soon, excited to try it, hopefully no issues, quite nervous as i never boat before

 

[Rick.]

Make sure you check for water prior to winter/freeze temperatures. Have a great summer with your boat. Best of luck. Rick.

 

[digong]

Thank you Rick, this is my first boat, while it is old, i am equally excited, enjoy your summer as well.