Dripless shaft seal question

Raider Ronnie

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captainlarry84

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Not sure which one you have. Can you post a picture? Dripless stuffing boxes start to drip for two reasons. One is they are out of adjustment. The second reason is that the water feed is blocked and the unit is not getting the water it needs to lubricate the mating surfaces. I would check the feed. Unusually if it has been run dry a while it is done.
 

Brooksie

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Sounds like you have the std, old fashion, stuffing box, with 3 or 4 rings of square flax/tallow packing material. If you haven't even adjusted it in 12 years, how could you ever beat that for service?? My advice, tighten it slightly (until 1-2 drops per minute) using a hammer and punch if wrenches won't fit in your keel; for the rest of the season. Repack it per easly found instructions when you haul, and don't bother with the new dripless stuffing boxes. They have problems of their own.

PS: If you decide to remove it and the shaft when you are hauled, replace the 12 year old hose and clamps with the best & proper stuff and if your wrench space is real tight, grind some notches in the nut & locknut for your punch & hammer method.
 
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Toolate

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Its usually an o Ring or 2 inside the donut with the allen set screws that holds the water out though if I am not mistaken. Just loosen them and slide the donut closer to the bellows to compress them a little more and retighten.

The older ones had 2 metallic faces that would wear into eachother creating the seal (I think). Not sure about anything newer than 12 years or so....
 

eyschulman

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Some of these units need new bellows and repair kit every seven years. Mine on a 440hp barely made five years. The rubber loses its spring and oil and bilge chemicals can hasten the decay. you may also have to dress the ring surfaces with wet sand paper. contact the manufacturer and get specifics.
 

captainlarry84

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Sounds like you have the std, old fashion, stuffing box, with 3 or 4 rings of square flax/tallow packing material. If you haven't even adjusted it in 12 years, how could you ever beat that for service?? My advice, tighten it slightly (until one drip per minute) using a hammer and punch if wrenches won't fit in your keel; for the rest of the season. Repack it per easly found instructions when you haul, and don't bother with the new dripless stuffing boxes. They have problems of their own.

PS: If you decide to remove it and the shaft when you are hauled, replace the 12 year old hose and champs with the best & proper stuff and if your wrench space is real tight, grind some notches in the nut & locknut for your punch & hammer method.

He sounds correct the box you are describing maybe a standard flax packed box. In either case I would check the water feed. I have seen on some Yanmars that they remove a zinc pencil to tap in the water, which is never good. I have seen some where they used the zinc pencil from the transmission oil cooler to feed the stuffing box. Very bad. It leaves the cooler unprotected plus with the water feed so low they clog easily with debris leaving your stuffing box to run dry.
If you have a flax stuffing box. First I would repack it with three loops. next the box gets tightened until it drips one drop every five seconds. Next run the boat and see if you are slighting water. If so gently tighten the nut until it almost stop. With the boat running at speed place your hand on the stuffing box it should be just a little warm, but not hot. It may take several adjustments to get it correctly. Lastly if you decide to go dripless it may not work, as the old shaft may be worn from the flax packing. Dripless boxes need a perfectly smooth surface to work correctly.
 

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