Guests - If You want access to member only forums on FM. You will gain access only when you Sign-in or Sign-Up on Fishing Minnesota.

It's easy - LOOK UPPER right menu.

Sign in to follow this  
Followers 0
mudslinger64

lower unit leaking lube

5 posts in this topic

after being on the lake today i was putting the boat away and i noticed lube was leaking from a hole by the upper plug hole on the lower unit.it was slightly higher than the plug and to the rear of it a little,is this a frost plug that popped?when i drained the lower unit this spring there was some water in it.i can't see any cracks anywhere it is only coming out of that little hole.the motor is a 1979 johnson 25 hp.

Share this post


Link to post
Share on other sites

smell it and verify it is lower unit oil. If it smells like gas it is unburned gas oil mix which is common when you trim your motor for the road. If you are sure it is lower unit oil likely places are drain and vent plug gaskets, Prop shaft seal, drive shaft seal and shift seal. The prop shaft is the most common cause fishing line can get wrapped there and will damage the seal. If motor is from 79 it is probably due to have a new seal kit installed. Wait till later in the season when the marinas get caught up. Just keep monitoring it and add more oil as needed till you get it fixed.

Share this post


Link to post
Share on other sites

i think your right about the unburnt gas and oil,i just went and looked at it again it looks greyish black and there is a little coming out of the exhaust hole also.i cracked open the drain for the lower unit and the lube that came out had a brownish yellow color to it not even close to the color of what is leaking out the side thanks i was getting worried.

Share this post


Link to post
Share on other sites

When you trim your motor the float in the carb has a tough time fighting the new gravity and a lot of times will loose causing the needle valve to open. Because when you shut your motor down your fuel lines were pressurized fuel will free flow out the carb and down the motor leg. When it mixes with water it tends to get a puss look and frothy. The best way to tell is to smell it. Nothing stinks like lower unit oil. If it smells like gas dont worry about it

Share this post


Link to post
Share on other sites

Quote:

when i drained the lower unit this spring there was some water in it.


You may have dodged a bullet here... you really should be draining and re-filling your lower unit lub in fall. The reasoning behind it is if you have water in your lower unit and let it sit outside over the winter the water will freeze and either damage a seal or crack the lower unit.

Keep an eye on it and check your lower unit lube periodically to see if your lube turns milky.

marine_man

Share this post


Link to post
Share on other sites
Guest
This topic is now closed to further replies.
Sign in to follow this  
Followers 0



  • Posts

    • ZachD
      Send me a pm for some ideas in the area. I plan on hunting Dayton and Monticello mainly but if those don't work out I need some backup plans.    
    • ZachD
      I sent you a private message.
    • Stick in Mud
      I am with you, net_man.  I *hate* that I can't C&R walleyes in the fall.  I mean, what's hooking mortality at 6-12 ft deep with artificial lures in October and November?  I've never had a fish not swim away, and I can't remember one that didn't do it in a hurry.  Drives me crazy, as fall trolling on Mille Lacs is one of my favorite ways to catch fish.  This year, thanks to the weather, we did get out in December...and the fishing was nuts.  If only we had been able to be out all fall...   I wonder if the night ban in the fall (even if we haven't hit our quote) has more to do with enforcement than anything else.  I have no idea what's said at meeting I ain't invited to. 
    • ZachD
      The big one in Sherburne I hunt a lot and even during firearm season I never see anyone close to me as I like to get back as well. During archery it is even easier usually I only see a truck here and there but the place is huge so you never see them.   You living in Andover there is a 200 acre public place like 10 mins away from you that doesn't get hardly any archery pressure I sometimes go there after work for a quick hunt and there is only a couple trucks there usually.   There is also a very small one on the way up to the big one in Sherburne that on spur of the moment I went to on gun opener and I was the absolutely only person there.   But really most every one for archery is going to have minimal pressure. 
    • ZachD
      Don't forget the flea and tick guard too my buddy found a tick on his lab when him and my dog where playing in my backyard last week.