Grey Sludge out of prop

Joined
Aug 31, 2012
Messages
27
I just got done running the motor on muffs to ensure it would start up after a carb rebuild. after fixing a small fuel leak everything is working great. When I was getting ready to put it away I saw this grey sludge coming from the prop. it is smooth and not gritty. Could it be un-burned fuel from having to prime the system twice because of the leak? Or is it something more serious like a blown prop seal. Am I good to water test my hard work or do I need to hold off?IMG_20120930_182314.jpgIMG_20120930_182352.jpg
 

kfa4303

Banned
Joined
Sep 17, 2010
Messages
6,094
Re: Grey Sludge out of prop

Hi Ballistic. If it's a 2-stroke motor, then it's probably just unburnt fuel/oil/water/exhaust gasses mixed together.
 

hooterville

Seaman
Joined
Feb 18, 2007
Messages
74
Re: Grey Sludge out of prop

Hi Ballistic. If it's a 2-stroke motor, then it's probably just unburnt fuel/oil/water/exhaust gasses mixed together.

what he said......I have noticed this on my Johnson in the past ....you only notice it in the driveway because its on muffs and motor is tilted down.....on the lake it cleans it out and if you use a transom saver it most likely dries out and you never would notice it unless you run it on muffs again.......at least this is what I have noticed on mine.......


If you are really worried check you lower unit oil to make sure it doesn't have water in it...
 
Joined
Aug 31, 2012
Messages
27
Re: Grey Sludge out of prop

Well I put a zip tie into the top plug of the lower unit and it is less than 1/4 in from the top. it is a greenish grey color and does not look foamy at all. I do not think it is leaking or have water on it. We are going with the unburnt fuel option and taking it out for a test of the rebuilt carb. Wish me luck.
 
Joined
Feb 17, 2012
Messages
2,906
Re: Grey Sludge out of prop

i asked the same question about mine months ago and they said to smell the oil. sounded wierd but it did smell of gas. the lower unit oil has a diffrent smell. the pics look the same as mine was which was unburnt gas and oil especially as i had been running on ears. like me you will proberly check the lower oil every trip until you are satisfied that you do not have a leak.
 

pdgs

Petty Officer 3rd Class
Joined
Sep 22, 2012
Messages
77
Re: Grey Sludge out of prop

It's just exhaust carbon mixed with a litle premixed fuel. It's comming from the insides of the exhaust tube inside the mid section. It's not a problem and may continue for a bit. Eventually it will all drain out.
 

emoney

Commander
Joined
Jul 19, 2010
Messages
2,551
Re: Grey Sludge out of prop

The smell test is the easiest. If it's "gassy" smelling, then all is well. If, however, it smells like gear oil, you need to drain that LU and have a real look.
 
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