flushing lower unit and oil change??

[kaboominator]

Hi i want to change the lower unit oil and flush it afterwards before i put new oil in. What product should i use to flush or is this recommended or possible? I would like to be able to do this all through drain plaug and vent hole. It s on a 1988 15 hp merc. Basically everything seems gummed up and tight with stretched throttle cables so i am going to clean up all the throttle linkage and install new cables, so i would liek to also have nice new gear oil in there. any suggestions?

 

[Mike722]

Re: flushing lower unit and oil change??

What about SeaFoam. Maybe a half and half mixture. Warming the lower unit up, running unit in forward / reverse at low idle. You may have to do 2-3 times depending on how gummed up it is.

If it is really bad you may have to take it apart.

I maybe nuts, but I would try it. What does anyone else think?

Mike

 

[emckelvy]

Re: flushing lower unit and oil change??

Probably the easiest thing to do would be to get a manual pump that goes in a quart bottle of hi-vis gear lube. With the hose connected to the drain hole on the lower unit, pump fluid out the vent hole until the discharge runs clean.

If it's really nasty in there, you may want to run the motor then do another drain/refill cycle.

That should clean it up pretty good. If your oil should become contaminated again, you might take a good look at your driveshaft/propshaft/shiftshaft oil seals for leakage.

BTW Wal-Mart has good deals on HI-Vis Marine Grade gear oil. Last time I was in there I saw a kit which included bottle of lube plus the pump. Or pick up a Sta-Lube pump at your local auto parts store.

HTH...........ed

 

[holbs]

Re: flushing lower unit and oil change??

Probably the easiest thing to do would be to get a manual pump that goes in a quart bottle of hi-vis gear lube. With the hose connected to the drain hole on the lower unit, pump fluid out the vent hole until the discharge runs clean.

If it's really nasty in there, you may want to run the motor then do another drain/refill cycle.

That should clean it up pretty good. If your oil should become contaminated again, you might take a good look at your driveshaft/propshaft/shiftshaft oil seals for leakage.

BTW Wal-Mart has good deals on HI-Vis Marine Grade gear oil. Last time I was in there I saw a kit which included bottle of lube plus the pump. Or pick up a Sta-Lube pump at your local auto parts store.

HTH...........ed

How hard is it to replace those seals? I have oil leaking out of where the water is sucked in.