Oil system on mercruiser preAlpha

[alesk565]

Hi Everyone,

I've have a question regarding my outdrive. I cannot figure out how the oil possibly would transport between the lower and the upper unit. Can it be two separate systems, one for the lower and one for the upper? When I tried to order a new gasket to to my impeller house, I got the answer that my impeller house was installed before 1970 since it was maid of aluminium(so it's quite old imo).

I will provide you with som pictures. On the lower unit I know, one is fill/drain bolt and one is to hold the lower impeller housing? In the upper unit from the outside, no 1 look like an damaged bolt. My conlusion from this pictures is that i have one fill/drain in every unit and that they are seperate.




Thanks for your time, pardon my english and best regards.
Alexander Skoglund

 

[04fxdwgi]

Top plug is the vent for when filling oil from the bottom plug. There is a passage, although quite small, that passes between the upper and lower sections and has an o-ring on it for a seal,seen on the 3rd picture.

It is a single oil system for the drive.

 

[Bt Doctur]

in the second pic 1 drain/fill plug, 2 vent plug usually not used , 3 flushing adaptor plug, usually not used.(does not hold in the waterpump assembly)
If someone drilled and plugged the oil passage, they were idiots

 

[alesk565]

Thanks for the replys.

04fxdwgi - I'm feeling a bit stupid now but can you please mark the hole you are talking about in my picture?

The holes I can see is for the driveshaft, waterpipe and two for the bolts between the upper and lower unit.

 

[smokeonthewater]

It's already marked in your picture... In pic 3 the oil hole is marked with a 1 and then the passage is marked with a 2...

 

[smokeonthewater]

Actually looking closer it does look like maybe it's plugged.... If so it shouldn't be.

 

[alesk565]

I'm getting a bit confused but I'm following along with your thoughts. The passage is plugged, in that case, as you say. By the way, the bearings at the driveshaft were stuck, due to hard rust.

 

[alesk565]

To update a bit, and maybe help some other with an antique outdrive...

contacted my dealer who said that he?d seen atleast one really old outdrive with separate oilsystems in the lower and upper unit. So now I will just apply some pressure in the fill hole to determine the overflow hole in the lower unit.

And then just hope that it will work to fill the upper unit through the ventplug without getting airpockets at critical places..

Thanks for your input guys, appreciate it!