loower unit oil

hey guy and girls here is my question im getting ready to put a impeller in my 1976 johnson seahorse 70 hp and what i am wanting to know is what is the right type of lower unit oil for this motor i want to make sure i put in exactly what goes in it i had the cowling off the motor the other day and this motor looks brand new so i want to keep it like that the compression on the motor was 118 to 120 on all cylenders any help will be helpful im sortta new to boating but not a newbie im new as far as working on them

Re: loower unit oil

I'm fairly new to boating and boat motors. The motor may not be new as I thought my powerhead was but it was actually kept fairly clean and the motor gaskets were in good shape. I removed the plugs and shoved my in wall camera inside and saw surface rust so I used the sea foam lubricant and fuel additive in my fuel as a double dose initially not knowing the history. Just found my compression tester yesterday so hopefully sometime this coming week I can get a test ran on the cylinders, fingers crossed of course. I wonder if they have a newbie, I bought my first boat with a outboard guide somewhere on this site as it could be helpful for all of us newbies who get boats with motors we Don know history on. I'm sure there's Carb stuff and air intake stuff I need to do but I still have yet to figure out what all I need to do.

Re: loower unit oil

Well you don't need to drain the lower unit oil to do the impeller change but it should be changed regularly and the drained oil inspected for condition and debris. I use the mercury brand myself.

Re: loower unit oil

dtnel said:

I wonder if they have a newbie, I bought my first boat with a outboard guide somewhere on this site as it could be helpful for all of us newbies who get boats with motors we Don know history on.

Click to expand...

See the Top Secret Files. Everything you need is in there.

Yankee-rose, the lower unit lube is usually marked as Hypoid 90W Gear Oil. Be sure to get one that is meant for lower units, as I think there is an automotive 90W gear oil that would not have the same protection against water intrusion. I've used West Marine brand, Whatever brand they sell at wal-mart (Mastertech, I think it is called), and Mercury brand. They have all performed just as well. As Kenmyfam states, you won't need to drain the gearcase to change out the impeller, but you should change that oil every year, and especially if you don't know the condition or history of the motor, including the last time the LU gear was changed out.

Rgds

Rgds

rgds

Re: loower unit oil

why not get the correct gear lube at your local Johnson-Evinrude dealer?