Why is water in lower unit oil? ['84 Seahorse 15hp]

[MGodwin9]

Was surprised to find about a pint of water when I was changing my LU oil. Being new to servicing this myself, I was curious about the potential sources for water intrusion other than the upper/lower screw seals. Any coaching would be appreciated. BTW - which publisher of shop/repair manuals is the preferred by this audience. Thanks

 

[jonesg]

Re: Why is water in lower unit oil? ['84 Seahorse 15hp]

www.outboardbooks.com

always replace drain screw seals, 90% of water intrusion happens there.

 

[bktheking]

Re: Why is water in lower unit oil? ['84 Seahorse 15hp]

Seals could be leaking under the pump, bearing carrier assembly or behind the carrier assembly or the drain/fill plug seals as well. To determine a pressure test can be done underwater to tell where the leak is coming from or you could just bite the bullet.

 

[Lostfisher]

Re: Why is water in lower unit oil? ['84 Seahorse 15hp]

seals are bad... Take off the lower unit take all the oil out and submerge it under water where it bubbles is where the lesk it, Just be careful not to strip the threads while putting the lower unit back together.

 

[Rick.]

Re: Why is water in lower unit oil? ['84 Seahorse 15hp]

How long was it running since you last checked it for water contamination? Normally I would suggest changing the oil and the fill/vent gaskets and hope your good. If you got a pint of water from it you had no oil at all so I'm wondering what the general condition of your gears are if you follow my drift. Were there lots of filings that came out with the water? Are you having any shifting concerns? Best of luck. Rick.

 

[Mas]

Re: Why is water in lower unit oil? ['84 Seahorse 15hp]

Was it even filled with gear lube last time? It would be very rare for all the lube to be displaced by water. I could imagine no lube overheating the LU causing the seals to fail allowing water easy entry.

Mas

 

[WIMUSKY]

Re: Why is water in lower unit oil? ['84 Seahorse 15hp]

Was surprised to find about a pint of water when I was changing my LU oil. Being new to servicing this myself, I was curious about the potential sources for water intrusion other than the upper/lower screw seals. Any coaching would be appreciated. BTW - which publisher of shop/repair manuals is the preferred by this audience. Thanks

You need to reseal the lower unit. If you've never done it before, I would have a shop do it just for peace of mind. They too can check the condition of gears, etc. You might as well change the impeller while it's apart too....

 

[R.Johnson]

Re: Why is water in lower unit oil? ['84 Seahorse 15hp]

Drive shaft seal, repair as needed

Prop shaft sea, repair as needed

Shift rod seal, repair as needed

Repace all outer housing O- Ring's, Prop shaft, drive shaft,, shift shaft

Ckeck for leakage with pressure, vacuam guage.

 

[kenmyfam]

Re: Why is water in lower unit oil? ['84 Seahorse 15hp]

Any of the seals and any of the plug washers.
That's about all there is to it. If you are in there then replace them all. Check the nylon washers first though. Could be that simple.

 

[MGodwin9]

Re: Why is water in lower unit oil? ['84 Seahorse 15hp]

All, Thanks for the counsel/advice. I might have exagerated the amount of water, but it was at least 8oz. with plenty of lube coming out afterwards. I checked and see that there is no seal/ring on top fill/vent screw. Will review other seals when I replace impeller/water pump next week. Thanks again.

 

[kenmyfam]

Re: Why is water in lower unit oil? ['84 Seahorse 15hp]

I checked and see that there is no seal/ring on top fill/vent screw.

That will do it every time !!!!
Replace and try again. Cheap fix if that is all it is.

 

[MGodwin9]

Re: Why is water in lower unit oil? ['84 Seahorse 15hp]

Checked LU after full day out on water. Only a tablespoon of water in lube. After reading in SELCO manual about prop shaft seals being damaged by fish line [they say it is major source of LU water intrusion], I removed prop and found wad of mono wrapped around shaft and rubber chips missing out of prop hub. Will partially submerging emptied LU into water produce bubbles to indicate where water intrusion is coming from or does LU have to be pressurized to show bubbles. Sorry, I did not do well in physics.

 

[scrampbell]

Re: Why is water in lower unit oil? ['84 Seahorse 15hp]

Will partially submerging emptied LU into water produce bubbles to indicate where water intrusion is coming from or does LU have to be pressurized to show bubbles?

Putting it underwater essentially pressurizes it. I've never done it, but I think what you want to do is put all the plugs into the LU as if it were full of oil (but you'll have it empty). Then when you put it under water the bubbles will come out. You may have to rotate the LU underwater if the leak is at the VERY bottom of the LU (like at the prop), but I'm guessing you'll see it.

Someone please correct me if I'm wrong.

 

[Mas]

Re: Why is water in lower unit oil? ['84 Seahorse 15hp]

Pressurize the LU with about 3-5 psi and look for bubbles.

 

[WIMUSKY]

Re: Why is water in lower unit oil? ['84 Seahorse 15hp]

Checked LU after full day out on water. Only a tablespoon of water in lube. After reading in SELCO manual about prop shaft seals being damaged by fish line [they say it is major source of LU water intrusion], I removed prop and found wad of mono wrapped around shaft and rubber chips missing out of prop hub. Will partially submerging emptied LU into water produce bubbles to indicate where water intrusion is coming from or does LU have to be pressurized to show bubbles. Sorry, I did not do well in physics.

Only a tablespoon of water? That's alot with only a day on the water. Don't forget, the water will mix with oil first. When the oil is saturated you get straight water. I can guarantee you're getting more than a tablespoon of water in your LU. Again, have it resealed so you can have years of worry free performance.

 

[kaferhaus]

Re: Why is water in lower unit oil? ['84 Seahorse 15hp]

I searched to no avail...but has anyone posted a "how to" on re-sealing a lower unit? Mine may need it and I'd rather do it myself.

the oil was contaminated but still very slick and thick... did not get any straight water out of it at all.... but likely it didn't let it sit long enough to separate.

And please don't tell me to buy a manual.... I cannot find one for a 1987 40HP Evinrude other than the seloc or clymer and they both suck.

 

[bonzoscott]

Re: Why is water in lower unit oil? ['84 Seahorse 15hp]

I have a '73 9.9 bought new. It has water intrusion. About 15 years ago is when I discovered it. It leaks nothing out, just water in. I took to a good shop and explained. They rebuilt and I thought I was good, but no, it did the same thing. I asked the shop about it and they said they did everything except an obsolete seal (cowan). But they charged me $200 anyway and didn't notify me of the problem at all. Like I said 15 years and I just change oil once a season but can't go out when it's cold. It would be nice to fix it.

 

[OldJohnson6hp]

Re: Why is water in lower unit oil? ['84 Seahorse 15hp]

Water seep in lower unit?? Check the following:

http://www.duckworksmagazine.com/06/columns/max/index1.htm

 

[1946Zephyr]

Re: Why is water in lower unit oil? ['84 Seahorse 15hp]

yea, I had an old 18 hp Evinrude one time that only water came out, when I drained it. I resealed it plus I had to have a new upper bearing installed. What fun.....

 

[kaferhaus]

Re: Why is water in lower unit oil? ['84 Seahorse 15hp]

Question can the bearing carrier be removed without taking the lower unit apart? I see the three bolts that fasten it to the lower unit housing... so if that carrier can be removed without taking the lower unit apart I can easily change the prop shaft seals.....