oil leaking from trim cylinder

I have a 1995 fresh water Merc 4.3LX I purchased new. I am noticing a little of oil on the water when I tilt the outdrive all the way up and sitting still in the water. It appears only to come from around the starboard trim cylinder piston. It is not enough to feel any oil when tilting the drive up while on the trailer (and dry). Do the seals not wipe the piston as well with age? I asked my dealer and they said they never heard of this. I must admit, it is very slight, only is visible for a few seconds, and most people wouldn't even notice it! The trim oil in the resivor looks fine as far as color and the level goes. I am hoping an experience Merc technician out there will know as this might sound familiar to you. homelite55@aol.com

Re: oil leaking from trim cylinder

If there is oil (or even a sheen on the water) it is because a seal is leaking. It may just be starting and it could be for any number of reasons that I won't even guess about. But if it's starting to leak, it will not heal itself and will eventually get worse.<br />The options are:<br />1 Don't mess with it.<br />2 Have the cylinder inspected and resealed.<br />3 Replace the offending cylinder with a new one.

Re: oil leaking from trim cylinder

The oil can also come from a bad seal in the drive.The ram shouldnt leak unless its been scratched or damaged.It contains "O" ring seals in the end of the ram.Can also be a hyd. line,or the diverter block on the bottom of the drive.

Re: oil leaking from trim cylinder

I changed the oil in the drive and it was just as blue and clean as possible. I removed the drive and pressure/vacuum checked it and it was fine. I do have one question. What is a diverter block in the bottom of the drive?

Re: oil leaking from trim cylinder

All the diverter block does is gives you a place to connect the inside trim/tilt hoses to the outside hoses.

Re: oil leaking from trim cylinder

Its a 'double acting cylinder'. It uses pressure to move both up & down. If it only leaks when the hyd. pressure is on it, you won't get water back into the system while its at rest. The outdrive may lower itself from the pressure of FWD thrust while the boat is moving due to the leak, but you shouldn't get water back into it then either.<br /><br />I'm not sure about the new ones, but on my old lift system, the rebuild kit is pretty cheap and easy to install. Make sure the rams are good and slick, you may have a bur, or some crud that is cutting or gouging the 'O' rings as the ram travels.

Re: oil leaking from trim cylinder

i would work a littel harder at being sure were the leak is from if it is from the cylinder it will milk out the system oil over time and be a big job to clean out<br /><br />you could be seeing a litel fuel or motor oil from the prop exaust on the water which will also leave a sheen thats why i recomend you check very carefully<br /><br />tommays

Re: oil leaking from trim cylinder

I noticed the same thing with my Alpha 1 - and it did in fact get worse. My problem turned out to be the hose and not the trim cylinder however. Just something to check. The good news with the hose is that they are relatively easy to replace.