Lower unit fluid amount 70 hp 1974

Hi Guys, I am going to change the fluid in the lower gear case of a 3 cyl 70 hp 1974 evinrude mechanical shift motor. I need to know how much 80 - 90 weight marine lube I need to pump in from the bottom drain screw .Also, should the motor be straight up and down or is it ok to have the motor tilted up/forward on the boat while I am filling up lower unit with the lube ? Thanks in advance, Vinny

Re: Lower unit fluid amount 70 hp 1974

Pump till it comes out the top hole....then close the top hole first....make sure you put new seals in the plugs..they are not reusable...better than getting water in the gear case


also straight is the best way....

Al

Re: Lower unit fluid amount 70 hp 1974

Thanks Al. here's the problem. I had the motor tilted forward yesterday when I squirted the gear lube up from the drain hole . I could hear the air coming out of the top hole and then the lube started to come out. I put the top stud in and then took the 24 oz. lube container away from the bottom drain screw and put the drain screw back in with a new crush washer installed. After looking everything over I started to think that maybe I could of got more lube in the lower end if the motor was straight up and down instead of slanted forward, I took note that I used about 12 oz. of lube from the new 24 oz. container. So , that is why I am asking does anyone know the correct amount of gear lube this motors lower unit should take ? If I am only a couple of oz.'s short I can probaly take my time and finish filling from the top. If I am off by a lot I will take the drain plug out and finish filling from the bottom. Hope I have explained myself well. Thanks

Re: Lower unit fluid amount 70 hp 1974

Lower it down and take out the top screw, if it doesnt flow out then you don't have enough.

Re: Lower unit fluid amount 70 hp 1974

you should be fine....there will always be a space in there...as you take the oil pump from bottom you loose some any ways....the gears are at the bottom an they are covered....

I change my oil at the end of the season since I live in the North East..in case any water got in it will not freeze......so if you live where it freezes for the winter..change before putting boat to bed for winter also for a secure feeling it will not freeze if any water got in....I never had water...but i stil do it...never now....better than a new unit,....

Al

Re: Lower unit fluid amount 70 hp 1974

According to a gearcase capacity chart, it should take 22...you are quite a ways off. I would remove the bottom plug, screw in you pump, remove the vent screw, top it up in the vertical position. Its ok if you are a little short, but 12 oz is not enough.

Re: Lower unit fluid amount 70 hp 1974

OK sorry..I re-read the post..I though you used 24oz..and seen you used 12...you can open the bottom...screw in the tube and then open the top...and fill....put engine straight....to get a level fill....

sorry for first post....

Al