Mercruiser 1 oil change help

[pickled]

I have a 1969 mercuriser outdrive and need to what the flusher hole in the lower unit is for, and if I fill the oil in the lower unit from the bottom till the oil comes out of the top vent hole? <br />Also I think the upper drive has its own oil fill and vent hole. <br />Thanks <br />Lloyd

 

[ASI Imperial]

Re: Mercruiser 1 oil change help

Hello Lloyd,<br /><br />Wellthe little hole in the bottom of the drive on the right sid is a watter outlet to flush the drive of dirt and debris. Remember there should not be and gear oil comming out of this hole.<br /><br />There is an oil passage that connects the top and bottom drives so the oil can flow.<br /><br />Yes fill the drive from the bottom there is a pump you can get at your local marine store that screwes into the lower gear oil plug. The reason to fill from the bottom is to eliminat air in the drive. Fill untill it comes out the top you should be fine.<br /><br />Happy boating<br /><br />Brian-ASI

 

[JB]

Re: Mercruiser 1 oil change help

Moving to I/O

 

[hoot]

Re: Mercruiser 1 oil change help

you may be correct in that you have seperate upper and lower cases also. i have seen in some post that this is true on some units.