View Full Version : Lower Unit Fluid
gberg41
04-02-2009, 05:37 AM
Lower unit fluid milkey colored. What are possible reasons for this problem?
southerncomfort1
04-02-2009, 05:44 AM
Lower unit seal leak....
stinkycat
04-02-2009, 06:29 AM
I believe when ever water gets in with the lower unit gear oil it will mix and turn milky.... as mentioned by southerncomfort1 your lower unit seal probably needs replacement.
jokerjim
04-02-2009, 06:46 AM
Could be the gaskets are leaking or missing on the lower unit fill and drain plugs.
cast_and_blast
04-02-2009, 07:49 AM
Could be fishing line around the prop seal too.
Scott
MarkG
04-02-2009, 12:17 PM
If you had just run the motor ,the oil could be frothed up.Sometimes that can make it look milky. If for sure it is water,(water and oil don't mix so you should be able to tell ) Then it could be something as simple as bad or missing drain plug O-rings. Do you replace them every time?
Could also be a bad propshaft or some other seal within the lower unit. If you are sure it is water,and not just "discolored" oil, (normal wear can discolor some oils ) and the O-rings were known to be good,then you may want to have a service shop pressure test the lower unit. If fails,then time for a lower unit seal kit.
LIKEWALLEYE
04-02-2009, 05:14 PM
Had the same excact thing happen to my buddys yamaha, i told him to replace the drain plug seals. He did and the next fall we drained it to find water. He took it in and had the inner and outer seals replaced. Cost was around 500.00 or so. Keep an eye on it so you dont completely hach the lower unit. Good luck and sorry for the bad news.
Jack G
04-05-2009, 10:00 PM
First things first. Jokerjim said it first but lets make sure you know just what he is saying. The two plugs that you remove to refill and/or drain your lower unit have small washer like seals on each of them. These seals are easily lost when changing lower unit oil if you are not careful. Check each plug to see if the seal is on the plug or possibly the seal came off the plug but stayed stuck around the hole left by the plug when you removed it.
Jack
yarcraft91
04-06-2009, 05:22 AM
More on the drain plug seals...
It's possible that part of a seal or some foreign object remained on the sealing surface, preventing a new seal from fully seating. I use a strong light to inspect the sealing surface for each drain plug before re-filling with new fluid. If part of the old seal or whatever are present, carefully remove it (i.e., don't scratch the sealing surface!).
I keep a ziploc bag with a dozen new seals in my lower unit fluid change kit, so I have no reason to re-use the old seals.