65hp Evinrude lower unit question

[magicnov]

While winteizing, I drained the lower unit fluid from my 1973 65hp evinrude this weekend and found that it was dark gray in color. I figure that this means that water got into the unit, but I'm not sure what to do or which seals to change, to prevent this from happening again. The fluid looked fine earlier in the season, but between then and now, I replaced the water pump and I'm wondering if this could be part of the problem. Any advice would be much appreciated.

David

 

[tashasdaddy]

Re: 65hp Evinrude lower unit question

i don't think you have a problem, usless water came out first. always replace the seals on the drain and vent screws, when changing.

 

[magicnov]

Re: 65hp Evinrude lower unit question

No water came out, but the oil was kind of a "battleship" gray in color when I drained it and I didn't think that was normal. I also replaced the nylon seals on the upper and lower drain plugs, but I'm not familiar with the vent screws that you mention.

David

 

[TN-25]

Re: 65hp Evinrude lower unit question

No water came out, but the oil was kind of a "battleship" gray in color when I drained it and I didn't think that was normal. I also replaced the nylon seals on the upper and lower drain plugs, but I'm not familiar with the vent screws that you mention.

David

I guess you could call the lower screw a drain plug and the upper one a vent screw.

Anyway, with new washers you have eliminated one source of water intrusion. You've changed the gear lube now, so I would simply check it periodically.

I was wondering, do you have an actual pump to force lube into the l.u. or are you using a squeeze bottle? What I'm thinking is possibly is that if you don't let the gear lube drain completely, then force fresh lube up from the drain plug until it runs clean out the vent hole, you may still have had some old residual lube in there. Just a thought. The pump method is superior for ensuring that fresh lube is forced in from below and the air bubbles are forced out. It doesn't hurt to pump more than necessary so that it flushes out some lube out the vent hole. Air bubbles could cause some degree of oil aeration and that might make the lube not appear clear (i.e. battleship grey).

If in the future you find the lube is getting milky, knowing that the plug washers were replaced I would look for another source of water intrusion. I'm thinking water tube grommet or a seal in the l.u. Anyway you should cross that bridge if and when you come to it.

NOTE: You have a 1973 model if it is a Powershift II model. If it is a 1972 model (50th anniversary series) it has a hydro-electic shift. Those all require the appropriate lower unit oil, so make absolutely certain it was the right stuff and the year is correct. If it is a 1973 it will likely be a model 65ELS73 (if a 20" shaft), or if a '72 model a 65ELS72 (see how easy it is to tell?)