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Lower unit oil

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Ronniewhite

Regular Contributor
The creamy looking stuff on the left is after 4 days in the water trolling about 2hrs a day. The stuff on the right is new. Should the lower unit oil look like that? There wasn't any water drain out first. It just drained out slow. I hav a video but it wont let me load it.
Screenshot_20230518-204945_Chrome.jpg
 
I no when I changed the impeller last year the rubber housing with the 6 bolts was chewed up a bit on the inside of it. If you guys think that is water in the oil would that be the reason?
 
Bullet has a valid point..

it does look like water in there though. I have definitely seen worse...but this is after only 4 days of use....

Either way, this needs to be addressed. Use a quality-rated MARINE gear oil... and might be time to change the seals..
 
slimbo3006 said:
Bullet has a valid point..

it does look like water in there though. I have definitely seen worse...but this is after only 4 days of use....

Either way, this needs to be addressed. Use a quality-rated MARINE gear oil... and might be time to change the seals..
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Like change the water pump you mean? What lower unit oil should I use? It a 2000 25hp 3cylinder Johnson long shaft. J25TEL3SS.
 
Ronniewhite said:
Sorry I don't know what you mean by water falling out of the suspension?
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What he means by this is that as it sits, the oil and water will separate from each other, The oil will float on top of the oil. Albeit, it might take a little time...

Any quality marine grade gear lube that meats your motor's weight rating will work fine (probably 80W-90 or 75W-90) Quicksliver will probably be fine, I usually use Yamalube or Amsoil just because of availability where I am.
 
The oil will float on top of the water. **


The reason for the marine grade oil is that it is designed to still maintain its lubricating properties with a higher percentage of water intrusion. I believe they also have more anti-foaming and corrosion inhibitors in them as well.


But the fact still remains that if there is in fact water in the oil, you need to find the leaky seal(s) and replace them
 
slimbo3006 said:
The oil will float on top of the water. **


The reason for the marine grade oil is that it is designed to still maintain its lubricating properties with a higher percentage of water intrusion. I believe they also have more anti-foaming and corrosion inhibitors in them as well.


But the fact still remains that if there is in fact water in the oil, you need to find the leaky seal(s) and replace them
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There's just the water pump and prop seals right? I'm going to put a new water pump in it because when I changed the impeller last year I noticed that the housing was chewed up. It's probably the original one.
 
slimbo3006 said:
What he means by this is that as it sits, the oil and water will separate from each other, The oil will float on top of the oil. Albeit, it might take a little time...

Any quality marine grade gear lube that meats your motor's weight rating will work fine (probably 80W-90 or 75W-90) Quicksliver will probably be fine, I usually use Yamalube or Amsoil just because of availability where I am.
Click to expand...
I just went and looked and the oil in the cup still looks the same as it did on Thursday.
 
Ronniewhite said:
There's just the water pump and prop seals right? I'm going to put a new water pump in it because when I changed the impeller last year I noticed that the housing was chewed up. It's probably the original one.
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Well I dont know what model you are working on so..... but yes usually the seals under the impeller and on the prop shaft... also the gaskets on the drain and fill screws.

look can up your model here and find a diagram and all the parts you need

Evinrude - Outboard OEM Parts | Boats.net

Buy OEM Parts for Evinrude, Outboard
www.boats.net www.boats.net
 
Ronniewhite said:
I just went and looked and the oil in the cup still looks the same as it did on Thursday.
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Pour it into a clear glass jar. Let it sit for several days. If there’s water, you will see a definite line near the bottom of the jar.
letting it sit in that opaque cup won’t tell you anything. The water will separate out & sink to the bottom, it’s denser. The remaining oil on top will always look like oil. You can’t see through your container sides to see if anything seperated.
edit…I just looked at your last container photo, it will probably be visible in the measuring cup, I was looking at your margarine container.
 
Edchris177 said:
Pour it into a clear glass jar. Let it sit for several days. If there’s water, you will see a definite line near the bottom of the jar.
letting it sit in that opaque cup won’t tell you anything. The water will separate out & sink to the bottom, it’s denser. The remaining oil on top will always look like oil. You can’t see through your container sides to see if anything seperated.
edit…I just looked at your last container photo, it will probably be visible in the measuring cup, I was looking at your margarine container.
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Okay. It may not separate. Why? If the lubricant is extreme quality, then it has enough higher molecular weight glycols to bind with the water and this forms the emulsionary suspension. The high pressure additive is branched alkyl esters of phosphoric acid or the organophosphate which serves as the lube agent for industrial grade oils. This is why we use this kind of lubricant in lower units where we know there may be water intrusion to the gear case. Regular gear oil for axles and transmissions does not have the same properties when exposed to water or moisture.
 
timguy said:
Okay. It may not separate. Why? If the lubricant is extreme quality, then it has enough higher molecular weight glycols to bind with the water and this forms the emulsionary suspension. The high pressure additive is branched alkyl esters of phosphoric acid or the organophosphate which serves as the lube agent for industrial grade oils. This is why we use this kind of lubricant in lower units where we know there may be water intrusion to the gear case. Regular gear oil for axles and transmissions does not have the same properties when exposed to water or moisture.
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Ya I don't think it's going too it's been a week now and it's still the same. I have a new Johnson water pump kit here that I got today. Hopefully get it in tomorrow.
 
There are some high-tech fluids that will absorb and hold water but frankly, I don’t believe the lower gear oils you buy for outboards, especially in the lower horsepowers are in that category.
in the last several years, I’ve had a dozen outboards that I’ve draiNed into into a clear cup container and left sit for several weeks. Every one of them, with water in it, separates as per the pictures I posted.
The systems we’re talking about are not very high tech. It’s a pinion gear, driving another gear. Been around for about 100 years now.
 
Edchris177 said:
There are some high-tech fluids that will absorb and hold water but frankly, I don’t believe the lower gear oils you buy for outboards, especially in the lower horsepowers are in that category.
in the last several years, I’ve had a dozen outboards that I’ve draiNed into into a clear cup container and left sit for several weeks. Every one of them, with water in it, separates as per the pictures I posted.
The systems we’re talking about are not very high tech. It’s a pinion gear, driving another gear. Been around for about 100 years now.
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I'm going to leave it there to see if it does happen . Wife doesn't want her cup back now anyway.
 
High molecular weight glycols should be at least 40% by weight. So yes, it depends on how much is in the "recipe". I have a drum of Mobile fully synthetic propeller shaft lube used in the ore carriers on Lake Superior. It costs about $4500 per drum. A chief engineer good friend and neighbor arranged for me to grab it when the fleet went to Exxon products. This lube is extremely rich in high mol weight glycols. It will suspend water almost indefinitely and still provide full lubrication/protection, with no additional wear on components safely to nearly 25%. Yes, my friend....it all depends on quality of the lubricant. Ed, you are accurate and truthful. Thanks.
 
So it's been a month and the oil went back to the color of fresh out of the bottle with no water In the bottom of the cup. I've tried to show pictures but it won't let me.
 
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