Lower Unit Oil Leak?

boat4fun83

Seaman Apprentice
Joined
Oct 19, 2008
Messages
45
First of all I have a 5.7 L mercruiser 1996 and alpha one gen 2 lower unit with an oil reservoir.

Over the summer I have slowly been losing oil in the reservoir. I have put maybe 15 hours on the boat this summer. It went from the full line nearly to the fill line following the four or five outings this summer.

Is this normal for the lower unit to use oil like this or do I likely have a leak somewhere? I have never seen oil in the engine compartment or on the floor.

Any suggestions?
 

Rocky_Road

Lieutenant Commander
Joined
Oct 8, 2008
Messages
1,798
Re: Lower Unit Oil Leak?

The proper thing to do is to drain the leg...and pressure test it.

But, that is way too complicated for the average boat owner. I would at least 'crack' the drain screw, and check for any signs of water intrusion.

Keep us posted!
 

boat4fun83

Seaman Apprentice
Joined
Oct 19, 2008
Messages
45
Re: Lower Unit Oil Leak?

do you think I could make a pressure tester using a blood pressure cuff and parts from the oil pump for refilling lower unit oil? Could I just connect the screw part from the oil pump to the pressure cuff and pump it up to where it should be? Or does the pressure have to be applied through oil reservoir?
 

Rocky_Road

Lieutenant Commander
Joined
Oct 8, 2008
Messages
1,798
Re: Lower Unit Oil Leak?

do you think I could make a pressure tester using a blood pressure cuff and parts from the oil pump for refilling lower unit oil? Could I just connect the screw part from the oil pump to the pressure cuff and pump it up to where it should be? Or does the pressure have to be applied through oil reservoir?

You need to clamp the reservoir line shut. The test is done with the lube drained from the outdrive, and done from the vent (top) screw.

Here are a couple of links to look at:


http://forums.iboats.com/showthread.php?t=44377

http://cgi.ebay.com/ebaymotors/Outd...emQQimsxZ20090727?IMSfp=TL0907271710004r24717
 
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