496Mag, Dissapearing drive fluid
#1
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From: Huntsville, AL
Ok, i have twin 496 Mags, closed cooling, bravo ones.
the starboard motor, looses drive fluid, like 1/3 of the resivor a week. running or not.
I have pulled the resevior, checked for leaks, chases teh tube running from it, to the fitting on the back side of the gible going to the drive. no leaks, or drips stains...... BUT it leaks in the bildge. not out side.
WTF, i am not the only one looking, and not the type people that dont know how to work on a motor. but its like a damn mistory where the fliud is leaking out. SIO much so I am ashamed to ask. But after going though MANY MANY bottles of fliud to make sure its always has some, (dont want to hurt a drive).. I want this fixed.
The port motor looses some but nothing like this........
what am i missing.
the starboard motor, looses drive fluid, like 1/3 of the resivor a week. running or not.
I have pulled the resevior, checked for leaks, chases teh tube running from it, to the fitting on the back side of the gible going to the drive. no leaks, or drips stains...... BUT it leaks in the bildge. not out side.
WTF, i am not the only one looking, and not the type people that dont know how to work on a motor. but its like a damn mistory where the fliud is leaking out. SIO much so I am ashamed to ask. But after going though MANY MANY bottles of fliud to make sure its always has some, (dont want to hurt a drive).. I want this fixed.
The port motor looses some but nothing like this........
what am i missing.
#2
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Joined: Nov 2010
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For starters, you'll want to pull the stern drive off the back of the boat to see if you have any drive oil sitting inside the u joint bellows. Pretty common for the yoke & seal area to wear out and leak and causing this type of complaint.
http://www.mercruiserparts.com/Show_...ift+Components
Good luck.
http://www.mercruiserparts.com/Show_...ift+Components
Good luck.
Last edited by lakematdude; 02-21-2013 at 02:37 PM.
#3
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From: Huntsville, AL
It is leaking in the bilge. not in the drive. I literally have put about 5 quarts though the system, int he past season, and its always in the bilge.
#4
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For example,
http://www.sterndrive.com/board/show...646&TopicID=42
Last edited by lakematdude; 02-21-2013 at 03:20 PM.
#5
Check the sensor on the bottle, I had one leaking & couldnt find it til I put a piece of paper under the bottle & it got wet. The fluid was running down the front of the engine was why it was so tough to find the leak.
#6
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From: Huntsville, AL
I have checked the sensor at tha bottom of the tank,. and SWORE i felt some slimyness to it, but then never figure it out.
will investigate further.
I have removed a Bravo before, but am not an expert, is this seal lakematdue is talking about replaceable by just removing the drive?
will investigate further.
I have removed a Bravo before, but am not an expert, is this seal lakematdue is talking about replaceable by just removing the drive?
#7
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#8
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Joined: Aug 2004
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From: Baton Rouge La.
correct, the oil that is sitting in the u joint bellows is leaking past the gimbal bearing & dust/grease seal and spilling into the bilge area. Unfortunately this is common, $$$.
For example,
http://www.sterndrive.com/board/show...646&topicid=42
For example,
http://www.sterndrive.com/board/show...646&topicid=42
#9
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From: Slidell, LA
I had the same problem. It was the yoke seal on the drive. Common problem on bravos. Leaked into the bellows until it spilled over into the bilge. Drained the drive oil and checked for metal shavings.Pulled the drive- drive fluid everywhere. Sent it to the shop. $300 later I had a leak free drive. Don't let it go. Good luck!



