Water in lower unit?

steplift20 · #1 03-26-2019, 02:31 PM

I think I'm getting water mixing with my lower unit, today and last year I noticed that when I drain my lower unit oil it comes out a little milky and a very light green and dark normal green if the seal is no good ,what and where are the seals? Are they the ones under the water impeller housing, I never did that before and don't know if I should bring it to my mechanic or try it myself ,it's a 1988 150 Mercury outboard, any help would be great thanks for any comebacks. I live in New Jersey I do have a mechanic but he is not as good as he used to be not his fault he go screwed really bad but that's ab other story

phatdaddy · #2 03-26-2019, 07:21 PM

If u think it s leaking, pull it and have it pressure tested, that should tell u if and where. I think u need special tools to remove the carrier bearing.
If it was mine, i would let a grown up do it

SkunkBoat · #3 03-26-2019, 07:47 PM

Sounds like you have water.
Could come from the top seal under the water pump or from the seal at the prop shaft.

Sometimes on some motors the top one can be changed with common tools ...if it is not stuck...
The bottom one needs tools and knowhow.

I would say drop the lower unit yourself and take it to a shop.
If a shop can't do that right I don't know what to say.
Do it ASAP because everyone is waking up and uncovering their boats....

It won't get better on its own.

An 88 Merc has given you a lot. If it runs good, a couple hundred is the price of a ticket to play.

phatdaddy · #4 03-26-2019, 08:04 PM

Forgot to ask, when u service, do you put fresh washers on screws, could be something that simple

oteps · #5 03-26-2019, 08:39 PM

I did one for a friend, but it was a little different. Had 2 nuts holding the carrier in. Didn't need any special tools. Yours will probably have a spanner type nut holding the carrier in. U should replace the carrier seal and o ring, plus the seal under the water pump and shifter too. If u r mechanically inclined I would try it. it needs new seals anyway. Look up the schematic for that motor and u will see the parts im talking about. Should be less than $40 for the seals.

Blue_Runner · #6 03-27-2019, 01:58 PM

Quote:

Originally Posted by phatdaddy

Forgot to ask, when u service, do you put fresh washers on screws, could be something that simple

CHECK THIS FIRST - one of my friends kept getting water in his LU. He would change the oil before he used it every time. Come to find out he did not have drain plug gaskets on either of the drain plug screws. So of course water was coming in.....

That is one thing - the other which Phatdaddy alluded to - those drain plug gaskets are cheap and should be replaced every time you change the oil. If you fail to do this they can wear out, get brittle, compressed, etc. over time, leading to water intrusion. Bottom line if you aren't already, spend $5 on the drain plug gaskets at every oil change. I've been doing this for 15 years and never a sign of water intrusion with over 1000 hours.

SkunkBoat · #7 03-27-2019, 04:47 PM

Quote:

Originally Posted by Blue_Runner

CHECK THIS FIRST - one of my friends kept getting water in his LU. He would change the oil before he used it every time. Come to find out he did not have drain plug gaskets on either of the drain plug screws. So of course water was coming in.....

That is one thing - the other which Phatdaddy alluded to - those drain plug gaskets are cheap and should be replaced every time you change the oil. If you fail to do this they can wear out, get brittle, compressed, etc. over time, leading to water intrusion. Bottom line if you aren't already, spend $5 on the drain plug gaskets at every oil change. I've been doing this for 15 years and never a sign of water intrusion with over 1000 hours.

I used to buy new gaskets and always had new screws if I chewed one up getting it off....or dropped it in the bucket of oil....

steplift20 · #8 03-27-2019, 05:00 PM

All you guys gave me good advice, first thing I'm going to do is replace the two o rinds on the screws then if I'm still getting water I'm giving it to my mechanic, I am ok at replacing things but I want it fixed right so I will let someone else who does that , I will let you know what happens after the gaskets are changed

steplift20 · #9 04-17-2019, 09:59 AM

Ok I didn't get it fixed yet but I changed the lower unit oil and ran the motor with ear muffs and didn't lower the motor in water, I changed the oil again and it was discollered again , I think it might be the seals below the water impeller housing, what do you think? I got a price to reseal the lower unit and was told about 600 dollars. That seems high to me what do you guys think? Thanks

SkunkBoat · #10 04-17-2019, 05:21 PM

it could be either or both...or a crack....

remove lower unit. take it to an outboard service shop. tell them what you you said here. Tell them to change the upper and lower seals, pressure test it, fill it up and charge you accordingly.
There is just no getting around it.

If you drop it off now you might be fishing when fluke season opens.