1968 20 hp "200" mercury

[Nicola]

Engine runs great and no problem on starting it up,
my question is there is a round hole right above bottom split section on lower unit where some lube comes out from it but no water on lower unit what is it that for??
TY Nicola

 

[usskydvr]

Re: 1968 20 hp "200" mercury

Ther should be two holes both with screw plugs in the lower unit. The one that is just below the propshaft line and about 1-2 inched from the front edge is the filler hole. The other is above the cavitation plate about 1 inch and about 3-4 inches from the front edge is the filler vent hole. You remove the lower plug, shove in the lube tube, hold it there, remove the upper vent screw, squeeze the lube tube until lube just comes out the vent. Hold the lube tube steady ( don't let it suck any lube back in) put the vent plug in ( this provides a vacuum to help keep the lube from coming out so fast) then you remove the lube tube and quickly put the filler plug back in.

 

[Nicola]

Re: 1968 20 hp "200" mercury

there is one more tiny little hole above those 2 front left side of lwer unit right above split line of bottom lower part it is mybe 1/16 of inch no drain plug or over fill plug I dont know if it make sense??

 

[usskydvr]

Re: 1968 20 hp "200" mercury

Hmm, got me. Can you post a pic?

 

[charly1954]

Engine runs great and no problem on starting it up,
my question is there is a round hole right above bottom split section on lower unit where some lube comes out from it but no water on lower unit what is it that for??
TY Nicola

I also have a 1968 Merc 200 20hp.(serial #2298982)
The top big screw is not the gearlub vent the small one just left of it is. There are 2 big screws(head about 1/2" dia.) and one very small screw just left of the top big screw. On mine just right of the top big screw it says FLUSH, no matter how hard you push the tube of oil it will not come out the big one. You add lub thru the bottom hole until it runs out the tiny hole. Make sure the orings are present and not chewed up or it can leak oil out or let water in.