Procedure for Changing Gear Oil

imported_rick

Petty Officer 2nd Class
Joined
Jul 12, 2006
Messages
113
When changing the gear oil in the lower unit, the Seloc manual I have says to have the "drive train" in the verticle position.

Does that mean the the engine should be tilted up all the way, making the prop shaft near verticle?

The manual also says to open the vent screw. This lower unit has two screws just below the cavitation plate towards the front, one forward of the other about three inches apart.

Which one of the two screws would be the vent screw?

Thanks in advance for your help.
 

milehighboater

Petty Officer 1st Class
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Jul 28, 2009
Messages
235
Re: Procedure for Changing Gear Oil

I don't know for sure without knowing the motor you have, more often than not the vent is going to be slightly higher than the fill screw. To have the "Drive train vertical" means to have the motor trimmed all the way down (prop shaft horizontal). Now you should have a drain screw all the way on the bottom near the nose of the lower unit. Make sure you can remove the fill screw before draining the lower unit, and have a set of replacement gaskets for all three plugs and you should be set.
 

imported_rick

Petty Officer 2nd Class
Joined
Jul 12, 2006
Messages
113
Re: Procedure for Changing Gear Oil

Thanks milehighboater

The motor is a 1980 115hp Chrysler

Here's a picture of the lower unit with the two screws I mentioned. Do you know which one is the vent screw or should I just remove both?

lowerunit.jpg


Thanks again,
Rick
 

foodfisher

Captain
Joined
Feb 18, 2009
Messages
3,756
Re: Procedure for Changing Gear Oil

Yes, one is fill the other is vent (should be marked accordingly). Drain is way under, near the skeg.
 

imported_rick

Petty Officer 2nd Class
Joined
Jul 12, 2006
Messages
113
Re: Procedure for Changing Gear Oil

Thanks foodfisher

I found the drain it was just the two "mystery" screws that easily baffled me. Unfortunatley they're not marked accordingly.

Would you be able to tell me which is the fill and which is the vent?

Reading general fill instructions from various sources, they mentioned filling into the drain hole, using a tube I guess, to push the air out through the vent. I assume that would be for LU's with one vent screw above the drain hole?

Thanks all, for helping a newbie, it's my first boat and I just want to be sure I don't fubar anything.

Rick
 

foodfisher

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Joined
Feb 18, 2009
Messages
3,756
Re: Procedure for Changing Gear Oil

They are just two holes into the same cavity. Your intension is to fill it as full as possible. Use the lower one to fill until the oil comes out the vent, then be quick to replace the screw. If they are even it won't matter which one is which. Let settle for a while to allow air bubbles to work their way out. Refill.
 

imported_rick

Petty Officer 2nd Class
Joined
Jul 12, 2006
Messages
113
Re: Procedure for Changing Gear Oil

Thanks again foodfisher for the instruction and patience. I just tend to get a little panicky when things are not completely intuitive. Plus, the Seloc manual is not very thorough or detailed enough for me to fully understand at times.

Rick
 
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