Association Forum - Lower unit oil color change

Assn Members Area · Join

Home.

Association Forum

Ships Store

Cruising

Racing

Technical Tips

Photo Gallery - New

Boat Search - Updated

Manuals & Brochures

Swap Meet

Links

Officer Flag Line & Staff

Bylaws & Constitution

Members Area

Join the Association

Notice:
The advice given on this site is based upon individual or quoted experience, yours may differ.
The Officers, Staff and members of this site only provide information based upon the concept that anyone utilizing this information does so at their own risk and holds harmless all contributors to this site.

Association Forum

Username:	Password:
Save Password
Forgot your Password?

All Forums

Catalina/Capri 25/250 Sailor's Forums

General Sailing Forum

Lower unit oil color change

New Topic

Topic Locked

Printer Friendly

Author

Topic

mrhistory
Deckhand

Member Avatar

2 Posts

Initially Posted - 08/30/2003 : 17:43:27

Hello, I changed my 8 h.p. Evenrude longshaft lower untiy oil about 60 hours of running time ago, and when I went to replace it today, it came out deep brown/black. The Evenrude manufacture's oil was am amber/golden yellow when I put it in 2 months ago. Is this salt water intrusion or is it aging to perfection (me being optimistic)?

Thanks for any help you can provide.

Edited by - on

mrhistory
Deckhand

Members Avatar

2 Posts

Response Posted - 08/30/2003 : 18:00:11

by the way...it's a 1992 edition, and this was only my 2nd time to change the oil (I bought it recently).

Edited by - on

Dave Bristle
Master Marine Consultant

Members Avatar

Djibouti
10005 Posts

Response Posted - 08/30/2003 : 19:05:13

Welcome, mr... In my experience, water in the lower unit oil turns it milky, not darker in color. But I'm not sure what would make it that much darker. In a 2-cycle, some of the partially combusted oil lubricates the drive shaft bearings, and some may be seeping down into the lower unit.

Dave Bristle - 1985 C-25 #5032 SR-FK-Dinette-Honda "Passage" in SW CT

Edited by - on

Douglas
Master Marine Consultant

Members Avatar

1595 Posts

Response Posted - 09/01/2003 : 12:10:21

My first thought is what type of oil was in there first and that if it mixed with the new oil perhaps that changed the color. My next thought was where does your engine exaust from and could some of the exaust or carbon from same be getting past a seal and into the lower unit. My last thought is for some reason its getting hot down there I mean realy hot like a bearing failure and the oil is cooked.

Doug&Ruth
Triska (Alberg 29)
Tacoma Wa.

Edited by - on

JimB517
Past Commodore

Members Avatar

USA
3285 Posts

Response Posted - 09/02/2003 : 20:14:11

Oil gets black when it gets hot. Change it again and monitor it. If it is milky THAT is a sign of water intrusion (looks like coffee with lots of milk in it - the way my wife drinks it). Water also causes some bubbles. Water is bad, means you need new lower seals. If it's just dark I say don't worry, just change it and make sure you are using the correct grade.

<img src="http://www.indiscipline.org/cat25/pictures/icon.jpg" border=0>Indiscipline 1978 FK #398

Edited by - on

atgep
Master Marine Consultant

Members Avatar

1009 Posts

Response Posted - 09/02/2003 : 23:31:06

Don't forget to check for metal. bearings,gears, etc going bad almost always shed some metal before they go BOOM! Look for shiny flakes in the oil when you change it. If you have metal in the recently changed fluid then you have internal issues. after you catch the fluid runa magnet through it to see what it picks up. bearings amd gears are almost aways made of steel. Good luck.

Edited by - on

deastburn
Captain

Members Avatar

USA
334 Posts

Response Posted - 09/03/2003 : 16:46:40

Jim is right: oil turns black from carbon, which is a biproduct of burning or overheating. Milkiness is from water intrusion, though a very small amount of milkiness is no cause for concern (but change the oil before you put her away for the winter).

Before panic sets in, I would change the lubricant to the recommended marine grade lower unit lubricant (I think usually an SAE 90 weight special purpose oil) and monitor closely. There are two possibilities: the wrong oil (maybe motor oil?)was put in by a PO and it carbonized; the motor was run at some point in time without any lubricant or with very low lubricant, and the carbon from the overheating remained in the gears. Doubtless a real mechanic (I am not) would come up with more possibilities. If everything seems to be working OK, just dump in some lube, run the motor for a couple weeks and then flush the lube out and check its color and consistency.

I have low memory (like my old computer) so I always change engine oil and lower unit lubricant at the end of the season and put a pot-it on the motor housing saying I did it when I store the motor!

Dave on "Wood Duck" (#2616)

Edited by - on

deastburn
Captain

Members Avatar

USA
334 Posts

Response Posted - 09/03/2003 : 16:49:28

Sorry, just re-read your post. Isn't 60 hours a long time without a change of lubricant? I forget what Honda recommends, but I think it is more frequent than that... Maybe the lubricant just got tired...

Dave on "Wood Duck" (#2616)

Edited by - on

Topic

New Topic

Topic Locked

Printer Friendly

Jump To:

Association Forum

Notice: The advice given on this site is based upon individual or quoted experience, yours may differ.
The Officers, Staff and members of this site only provide information based upon the concept that anyone utilizing this information does so at their own risk and holds harmless all contributors to this site.