Mercuriser lower unitwater leaks

"I have a Pre-Alpha or “R”

"I have a Pre-Alpha or “R” outdrive on my 1977 Mark Twain 180VBR boat that is leaking water into the engine compartment. Over time it has increased in the amount of water that leaks in. So far the bilge pump has been able to handle it, but now I want to sell the boat and need to fix this leaking problem. Besides, I am increasingly nervous about the bilge pump being always available or able to handle the inflow.

Here’s what I have done:

Removed the stern drive.

1. The exhaust bellows clamp was loose, I tightened it, but I understand this isn't a required bellows really anyway.

2. I cannot find a crack or leak in the U-Joint Bellows or the shift cable bellows, but if these are cracked can water leak into the engine compartment thru them?
I probably need to look a lot more carefully. The bellows tubes are in very good condition and appear to be newer.

3. The exhaust bellows and u-joint bellows have some water inside them(?).

Any suggestions? Thanks."

Water can definitely leak thro

Water can definitely leak through cracks in the rubber on the upper bellow or shift cable. Also check all rubber hoses and rubber connections on manifolds inside the engine compartment. I had a leak on one once upon a time and anytime the engine was running water poured down from the leaky 3inch manifold rubber joint. I tightened the clamp and it stopped!!

"Water can get into the boat i

"Water can get into the boat if the ujoint bellows leaks, but not the outside exhaust bellows. If the ujoint has water in it, then it is either dry rotted or torn(sometimes the hose clamp can wear a hole in it, if it's not installed in the correct location). Also, the large rubber ring leading into the bellows can leak if it's damaged or not glued in well.Dryrot splits tend to be on the bottom of the bellows where they're hard to see."

"Thank you very much, Ken and

"Thank you very much, Ken and Sam for the excellent advice. I will use it and continue pressing forward with my repair. I will try to let you know what happens and what I finally end up doing to get the leak stopped - just to keep the knowledge base growing!

Gary"