I have searched

R

reward_1000

Cadet
Joined
May 16, 2010
Messages
8
I have a 1978 mercruiser 470 that I am doing an impeller change on. It is not that hard of a job, but I am trying to figure out how to fill the lower unit. I have found the fill for the top unit but can not find any fill or vents for the lower unit. There was very little oil in the lower unit when I took it apart. My dad is working with me and he can not find any of the service holes either. I have down loaded the factory manuals and bought a clymers manual and can not match any of them up to my lower unit. I will try and get pictures this week just checking to see if anyone has any ideas.
 
Bondo

Bondo

Moderator
Staff member
Joined
Apr 17, 2002
Messages
70,525
Re: I have searched

Ayuh,... The Fill/ drain hole should be on the leading edge, portside of the bullet...
 
Don S

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: I have searched

I have found the fill for the top unit but can not find any fill or vents for the lower unit.
Click to expand...

That is NOT how it's done. You use a gear lube pump and pump gear lube in from the drain screw at the bottom of the drive, until it comes out the vent screw at the top of the drive.

You might want to head up to the adults only sticky (1st thread in this forum) and download the OEM service manuals for your engine and drive.
 
R

reward_1000

Cadet
Joined
May 16, 2010
Messages
8
Re: I have searched

I have downloaded the manuals like I said it does not match up. I know to fill it from the bottom to the top. I have purchased the pump to help with this, still trying to find the fill hole though.
 
Don S

Don S

Honorary Moderator Emeritus
Joined
Aug 31, 2004
Messages
62,321
Re: I have searched

You do not fill the upper and lower seperately. You fill from the bottom of the lower unit till it comes out the vent in the upper.

attachment.php
 

Attachments

  • fill.JPG
    fill.JPG
    107.2 KB · Views: 0
R

reward_1000

Cadet
Joined
May 16, 2010
Messages
8
Re: I have searched

I forgot step 1: remove head from rear end and look harder. My dad and I have looked at this thing a dozen times each and missed it every time. Until today, somebody must have came over last night and put it in the lower unit. So now we know where it is, thanks for the insight guys.
 
You must log in or register to reply here.
Top