Rudder Stuffing Box

[HeatherAlyssa]

Hello Trawler friends!

OK, I give up. I have yet to find any clear instructions on how to replace the stuffing box on my 1999 Mainship 350/390 rudder post. Which one of these unscrews? I’m assuming the one on the bottom since I see some threads. I know the green patina looks terrible. That will definitely be taken care of. Thank you in advance. Alex

Heather Alyssa
Mainship 350/390
Solomons, MD

 

[O C Diver]

With the boat out of the water, remove the tiller arm on the top of the shaft. Then loosen the set screw(s) in the top brass ring. With 2 wrenchs (one on each hex) unscrew the top hex while keeping the bottom one stationary. Once completely unscrewed, the top hex piece should slide (with effort) off the top of the rudder shaft. Inside will be the packing waxed rope which I would replace. Clean the rest of it up and reassemble. No need to pull the bottom piece out of the hull.

That's how it appears to me anyway...

Ted

 

[Comodave]

+1 on that.

 

[angus99]

I think you’ve gotten good advice but I’d go a step further and drop the rudder shaft to check for crevice corrosion—especially if the boat ever sat unused for long periods in warm salt water (maybe before you bought it?). Inside a stern tube is a perfect low-oxygen place for it to happen. Both of my stainless rudder shafts were eaten up with it. I had them inspected and recoated with Inconel, which is more resistant to crevice corrosion.

 

[HeatherAlyssa]

Wow!!! Thank you for the replies everyone.

 

[Comodave]

Those shafts look like new after rework.

 

[angus99]

Those shafts look like new after rework.

I was really pleased with the outcome. Had the work done by a PA firm that specializes in stainless industrial and agricultural pump shafts. Still not cheap but less costly than some company with “Marine” in their name.

 

[angus99]

FWIW to the OP, my steering gear was a mess. There had been leaks in the past and evidence of some half-assed repairs at some point in her life. Nothing was bonded properly so the stainless bolts were wasting and the corrosion and verdigris were extensive. The steering gear on a Defever was more than I wanted to take on so I had the yard pull and clean everything and install new bearings and mounting hardware. I went back with Duramax packing as extra insurance against leaks. Finally, I reworked the entire bonding system in the boat with new, tinned wire, proper lugs and threaded connections. When I did the silver/silver chloride test on the steering gear, everything was protected.

 

[HeatherAlyssa]

That’s First Class right there. Beautiful!!!

 

[kapnd]

I like to have a grease nipple just under the packing. If the boat is to be unused for a while, I give it a few strokes of grease, while working the steering lock to lock to displace the water that will otherwise sit in the lower "bushing" area.

 

[Alaskan Sea-Duction]

What do you use to get the "green' off the metal housing? I want to clean my thru hulls, rudder and shaft housings.

 

[Comodave]

Angus, what was the approximate cost and do you have the contact info for the company that did the work?

 

[O C Diver]

What do you use to get the "green' off the metal housing? I want to clean my thru hulls, rudder and shaft housings.

Wire brush and elbow grease. The parts that can be removed from the boat can be cleaned on a wire wheel on a bench grinder or put in a cabinet sand blaster.

Ted

 

[angus99]

Angus, what was the approximate cost and do you have the contact info for the company that did the work?

Have to check my recipts and get back to you on the costs, I had the work done at Worton Creek Marina on the eastern shore of the Chesapeake. Great folks and prices are reasonable, but a fair distance from your neighborhood .

Wire brush and elbow grease. The parts that can be removed from the boat can be cleaned on a wire wheel on a bench grinder or put in a cabinet sand blaster.

Ted

Exactly! The verdigris isn’t harmful, but my gear was so covered in it and other stuff, I wanted it all cleaned up to verify that it was still intact.

 

[Comodave]

Oops, I meant to ask you about the cost of refurbishing the rudder shafts and who did the work.

 

[angus99]

Angus, what was the approximate cost and do you have the contact info for the company that did the work?

Dave, this is the outfit I used. Industrial Coatings Thermal Spray - Reneuxit

Out in the boonies but they do first-class work.

I paid about a boat unit ($1K) for both shafts, IIRC.

 

[Comodave]

Thanks for the info Angus. They really look nice.

 

[HeatherAlyssa]

Yeah, those look great. I think I’m going to keep it simple this year, and just repack the stuffing box and knock off some of that green patina. I have about 40 other boat projects to do, and since this one will prevent me from splashing this spring, I need to go the easy route. It’s good to know there are people out there that can perform that service though.

 

[FF]

"I wanted it all cleaned up to verify that it was still intact."

Hit it with a small hammer or wrench.

 

[HeatherAlyssa]

**Update** So I loosened the set screws and used a packing wrench, I attempted to unscrew the nut on top in a counter clockwise fashion. That sucker didn’t budge.

 

[O C Diver]

Have someone move the rudder while you are looking at the stuffing box. Does the ring with the set screws turn with the rudder shaft or remain stationary with the stuffing box? Can you post a picture of your packing wrench with a tape measure along side?

Ted

 

[HeatherAlyssa]

Sure. Once I leave IHOP!

 

[HeatherAlyssa]

O C, the ring with the set screw moves.

 

[Island Cessna]

You need to turn the bottom nut clockwise first. It is a jam nut and the upper packing retainer will not turn until it is loosened. The light plumber’s wrench may be too weak to break the nut loose. Judicious use of a pipe wrench, perhaps softened with cardboard to lessen chewing up the nut, may work better.
Be careful..... I have not seen a Mainship rudder in real life but internet photo of one shows that there is no shoe supporting the bottom of the rudder. I suspect the set screw collar above the parking gland may be holding the rudder from dropping. Depending on what is above for a bearing, it could just be there to prevent the rudder dropping out whole changing the upper bearing, in which case no worries.

 

[HeatherAlyssa]

Yeah. You’re right. No shoe. I’ll get back at it tomorrow. I bought one of these hoping it would also work. Thanks for the help guys.

 

[O C Diver]

As crude as this sounds, you will probably need a pair of big pipe wrenches. As corroded together as that mess is, a pair of 20 to 24" wrenches is what you need to give you enough leverage. The purpose of two identical wrenches is to be able to pull one against the other. Take a trip to Harbor Freight or one of the other Chinese tool sellers and buy a pair of aluminum handle pipe wrenches.

Ted

 

[FF]

"I attempted to unscrew the nut on top in a counter clockwise fashion. That sucker didn’t budge."

With green growing it takes a bunch of force to loosen the nut.

A cold chisel and 2-3 lb hammer should get the nut started and then a wrench might get it looser. Hit the nut on one of the corners in the right direction.

Spray with PB Blaster or your favorite goop a few days in advance.

 

[Island Cessna]

"I attempted to unscrew the nut on top in a counter clockwise fashion. That sucker didn’t budge."

Two large pipe or open end wrenches as OC Diver suggests, but if only one, turn the narrower lower jam nut. The vice grip is probably too short. Perhaps tap the lower nut with a hammer to loosen the threads, but I’d be careful with a chisel as the soft bronze will cut without transferring much force to the threads.

The purpose of the lower nut is to apply pressure to “jam” the threads so that the upper packing nut won’t budge! It is narrower, and hence easier un-jam.

 

[FF]

When using a chisel on the jam nut the chisel is kept parallel to the corner of the nut.

This might bang a grove in it but not cut the corner off.

 

[HeatherAlyssa]

I thought I would update you guys. I finally got the jam nut and stuffing box nut loose. I used PB blaster and a pipe wrench. I appreciate all of your help.