Plastic packing box

Sep 8, 2009
19
Hunter 335 Lake Guntersville
The packing box on my 1999 Hunter 335 is made out of some sort of plastic material. There is no lock locking nut. The packing nut is held in place with a piece of wire running through a hole in the adjustable packing nut and the fixed nut. Where these standard on this Hunter model? When I adjust the packing nut, do I need to align to the existing holes so I can put the wire back in place? This does not appear to allow me to fine tune the packing nut. Any advice would be greatly appreciated.
 
Jan 4, 2006
6,444
Hunter 310 West Vancouver, B.C.
Wow ! Just what have you there ?

Mine is a 1999 Hunter and it came with the standard brass packing gland. As you say, with a wire for keeping the nut in place, there's no way for fine adjustment. I know the nylon packing gland does have a locking nut in a feeble attempt to keep the nut in place.

Hate to say it, but you may be forced to replace it with a proper packing gland ................ and all the effort that goes with it. My condolences.

Any chance you could send a few close up photos of this little marvel ?
 
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Likes: ggrizzard
Jan 22, 2008
68
Hunter 30_88-94 Ipswich, Ma MA
We had a plastic bushing type shaft seal on our 1992 Hunter 30. You’re correct on both questions, there is no fine adjustment and you need to line up the holes in the flanges to put a wire or cotter pin thru to hold it in place. I bought a large pair of channel locks to help with then adjustments, which is trial and error till you get the drip right.
About five years ago, I put in a PYI, PSS drip less shaft seal. No more scrapped knuckles, baling water out from under the engine, or running down below while motoring underway to check the drip. Now it’s just check the set screw periodically. It’s an expensive installation for sure, but we’ll worth it.
 
Jul 7, 2004
8,402
Hunter 30T Cheney, KS
Likewise on my '91 H30. I replaced my plastic stuffing box with a LasDrop Gen II dripless seal.
 
Jan 19, 2010
12,362
Hobie 16 & Rhodes 22 Skeeter Charleston
Six posts ... six different terms to describe the same system.. you got to love the sailing lingo ...<evil grin>
 
Jul 7, 2004
8,402
Hunter 30T Cheney, KS
WIKI -
Components
A stuffing box of a sailing boat will have a stern tube that is slightly bigger than the prop shaft. It will also have packing nut threads or a gland nut. The packing is inside the gland nut and creates the seal. The shaft is wrapped by the packing and put in the gland nut. Through tightening it onto the stern tube, the packing is compressed, creating a seal against the shaft.[2] Creating a proper plunger alignment is critical for correct flow and a long wear life. Stuffing box components are of stainless steel, brass or other application-specific materials.

Gland
A gland is a general type of stuffing box, used to seal a rotating or reciprocating shaft against a fluid. The most common example is in the head of a tap (faucet) where the gland is usually packed with string which has been soaked in tallow or similar grease. The gland nut allows the packing material to be compressed to form a watertight seal and prevent water leaking up the shaft when the tap is turned on. The gland at the rotating shaft of a centrifugal pump may be packed in a similar way and graphite grease used to accommodate continuous operation. The linear seal around the piston rod of a double acting steam piston is also known as a gland, particularly in marine applications. Likewise the shaft of a handpump or wind pump is sealed with a gland where the shaft exits the borehole.
 
Sep 8, 2009
19
Hunter 335 Lake Guntersville
I really appreciate all the comments I have received. Very helpful. I now have another questions: I have come across a used brass packing box from another Hunter/Yanmar. I'm almost certain the shaft size is the same as mine, but will confirm tomorrow. I can buy the brass packing box for a fraction of the cost of a new dripless coupling. Does anyone know how difficult it will be to swap out the plastic for brass?
 
Jul 7, 2004
8,402
Hunter 30T Cheney, KS
I really appreciate all the comments I have received. Very helpful. I now have another questions: I have come across a used brass packing box from another Hunter/Yanmar. I'm almost certain the shaft size is the same as mine, but will confirm tomorrow. I can buy the brass packing box for a fraction of the cost of a new dripless coupling. Does anyone know how difficult it will be to swap out the plastic for brass?
It ain't easy. You probably will have to drop the rudder to be able to slide the propshaft aft far enough to get the old seal off and new one on. But wait, there's more! The hard part is usually getting the transmission coupling off of the shaft end. Just don't beat it ! Same if you were going dripless.
Good time to replace the cutlass bearing if it needs it
 
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Rick D

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Jun 14, 2008
7,131
Hunter Legend 40.5 Shoreline Marina Long Beach CA
We had a plastic bushing type shaft seal on our 1992 Hunter 30. You’re correct on both questions, there is no fine adjustment and you need to line up the holes in the flanges to put a wire or cotter pin thru to hold it in place. I bought a large pair of channel locks to help with then adjustments, which is trial and error till you get the drip right.
About five years ago, I put in a PYI, PSS drip less shaft seal. No more scrapped knuckles, baling water out from under the engine, or running down below while motoring underway to check the drip. Now it’s just check the set screw periodically. It’s an expensive installation for sure, but we’ll worth it.
+1 Art. I did the same on my 32 Vision.
 
Sep 8, 2009
19
Hunter 335 Lake Guntersville
Wow ! Just what have you there ?

Mine is a 1999 Hunter and it came with the standard brass packing gland. As you say, with a wire for keeping the nut in place, there's no way for fine adjustment. I know the nylon packing gland does have a locking nut in a feeble attempt to keep the nut in place.

Hate to say it, but you may be forced to replace it with a proper packing gland ................ and all the effort that goes with it. My condolences.

Any chance you could send a few close up photos of this little marvel ?Photo attached
 

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Sep 8, 2009
19
Hunter 335 Lake Guntersville
Thanks again to everyone who responded. After much consideration (and a couple of glasses of wine) I've decided to take the easy way out for now and do nothing. I'll revisit the issue when I next haul the boat. One thing I may try in the meantime is to drill an additional whole, if necessary, after adjusting the packing. If I can't line it up to existing holes, I'm fairly sure I can get my right angle drill in a position to drill a new hole and then wire it. Not an elegant solution, but one that may be able to serve me for a while.
 
Sep 8, 2009
19
Hunter 335 Lake Guntersville
Only 1 clamp :yikes:
Good catch - I was so focused on the packing box issue I didn't notice the single clamp. This entire episode, including the single clamp, makes me wonder about other "economy" measures Hunter took - many of which may not be readily visible.
 
Jul 7, 2004
8,402
Hunter 30T Cheney, KS
Good catch - I was so focused on the packing box issue I didn't notice the single clamp. This entire episode, including the single clamp, makes me wonder about other "economy" measures Hunter took - many of which may not be readily visible.
Not all Hunters are like that. Mine wasn't, but I replaced it anyway with a dripless. You could still double clamp it without taking it apart.
 
Jan 4, 2006
6,444
Hunter 310 West Vancouver, B.C.
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That is so wrong in so many ways. I've never heard of Hunter using a bronze prop shaft in 1999 models. Are you sure the boat's not a forgery :biggrin: ? Maybe check your hull ID and see if it conforms to normal numbers.

Given your situation, I'd probably do the same until next fall. If you do try to tighten the packing nut (tighten 1/2 a flat at a time), be careful nothing happens while you have the wire out when the shaft is running for testing purposes. It doesn't look like you have much clearance left on the packing.

You can make it as good as new next fall with a new SS shaft, new shaft coupling, and a proper gland seal.

Best of luck.
 

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