Gear Oil for a 1968 Johnson 25 horse, pull rope engine

Ok I've dug and dug around the website and did a lot of reading and talking to people and now I'm doing my posting about gear oil. I drained the oil out of my
engine over the weekend and it came out brown milky consistency. I got Pennzoil Hi/Vis Marine 80/90 weight lower unit gear oil. Is this right? theidiot at the boat repair shop says that it is. I just want to double check
with you guys before I replace it. It is obvious that the weight of the oil is different. It's a shinny brown color and doesn’t look foamy to me. Is that they way it should be? Do they make that brown gear oil any more? Is it
ok to replace it with the 80/90 gear oil? Shouldn't I clean out all the brown oil before I replace it? (1968 Johnson 25 horse, pull rope engine). Thanks for all the help.

Roscoe

Re: Gear Oil for a 1968 Johnson 25 horse, pull rope engine

Are you sure about the year and HP?? Can you post the model number of your motor??

Re: Gear Oil for a 1968 Johnson 25 horse, pull rope engine

Well if the old lube comes out the consistency and color of vanilla milkshake you have water getting into the LU....a bad thing, may be time for new seals. New seals on my old 73 Merc 500 and a driveshaft resurfacing and new waterpump cost me about $125 3 years ago. If it's just brown and frothy it's probably just old lube and still needs to be changed. Your new Pennzoil LU lube should be okay, unless the label says its for a certain hp rating. But as a general rule of thumb, 80-90 wt. marine lube should do. It's a different color cause it's clean and fresh. Service the LU by pumping new lube into the LU, remove bottom drain plug...attach pump, remove top vent plug and pump the new lube in until it belches out the top vent hole...the old stuff will come out first, yuk. I put a coffee can below my LU when doing this. Be sure to check/change the washers for both the drain and vent plugs...if they're worn this could be where the water's getting in. You can get a pump for less than $5 at Wally World or other places.

Re: Gear Oil for a 1968 Johnson 25 horse, pull rope engine

Thanks a bunch puts my mind to rest. I don't have my model number on me but I will post it.

The drain plugs did'nt have washers. But I'll check again
and change them tonignt.

Re: Gear Oil for a 1968 Johnson 25 horse, pull rope engine

Roscoe_Floyd said:

Thanks a bunch puts my mind to rest. I don't have my model number on me but I will post it.

The drain plugs did'nt have washers. But I'll check again
and change them tonignt.

Click to expand...

Re: Gear Oil for a 1968 Johnson 25 horse, pull rope engine

Sorry about that it's a 1969 Johnson 25 horse model 25RL69D. Does this make a difference? I've not changed the gear oil yet. The oil is not like a vanilla shake. It's more like a light brown color. Am I worried about nothing? Any gear oil like the guy says will do fine. Thanks for your help, maybe I'm concerned about nothing.

Re: Gear Oil for a 1968 Johnson 25 horse, pull rope engine

90 or 80 weight hivis is the correct gearcase oil for that engine. Get fresh washers and see if the milkyness goes away. Coffee w/ cream colour indicates water intrusion, but not as bad as a milkshake.

Re: Gear Oil for a 1968 Johnson 25 horse, pull rope engine

Ditto. Put fresh lube in there and new washers on the vent/drain plugs. Then take it out on the water. If you're lucky, that'll do the trick. It's a good idea to change/refresh the lube at least once a year when you're doing your pre-season maintenance/prep for putting it on the water.

Re: Gear Oil for a 1968 Johnson 25 horse, pull rope engine

Thanks guys what a great group. Yes sir will do.