intermittent outdrive leak

Hi
I'm new here and new to owning a boat . I have a 1984 mercruiser 3.0 and it leaks water into the boat around the outdrive but ONLY when its trimmed up . When I drop the trim all the way the leak stops . I have done some research and bought a manual and I am preparing to change the belows if nescessary .however speaking as someone who knows nothing about sterndrives it seems to me that if it is the belows it would leak constantly . I am going to put water inside the boat (staying well under the starter of corse ) today when i get home and see if I can detect just where its leaking .
Any thoughts on the matter would be appreciated
Thanks

Re: intermittent outdrive leak

Don't bother with the water-in-the-hull thing. Leaking when trimmed up expands the bellows, opening the crack.

Stern drives require periodic maintenance \ replacement of bellows, impellers, and a few other items. Read up on this forum and you'll learn a ton. U-Joints, gimbal bearing, upper or lower seal kits, ignition wires & associated parts, steering \ shift cables, interrupter switch, and the list goes on. Cost of boating. They're NOT like cars.

If you're not POSITIVE that bellows (all of them, not just one) were replaced in the recent past then get them done. You should also replace the water impeller and housing while there, plus anything else your trusted, certified, Mercruiser mechanic recommends upon careful inspection.

Just my $.02.

Oh, and download the manuals from this site -- the one you bought (if Clymer or other generic type) will only be useful as a knee pad.

Re: intermittent outdrive leak

Grand Larsony said:

Don't bother with the water-in-the-hull thing. Leaking when trimmed up expands the bellows, opening the crack.

Stern drives require periodic maintenance \ replacement of bellows, impellers, and a few other items. Read up on this forum and you'll learn a ton. U-Joints, gimbal bearing, upper or lower seal kits, ignition wires & associated parts, steering \ shift cables, interrupter switch, and the list goes on. Cost of boating. They're NOT like cars.

If you're not POSITIVE that bellows (all of them, not just one) were replaced in the recent past then get them done. You should also replace the water impeller and housing while there, plus anything else your trusted, certified, Mercruiser mechanic recommends upon careful inspection.

Just my $.02.

Oh, and download the manuals from this site -- the one you bought (if Clymer or other generic type) will only be useful as a knee pad.

Click to expand...

so do you recommend the seloc manual? thas all I see on this site