Proper Wrench for Stuffing Box Maintenance

May 28, 2015
280
Catalina 385 Atlantic Highlands, NJ
What is the proper wrench/tool to loosen both the lock nut and tighten the packing nut for a stuffing box. I’ve seen adjustable wrenches, channel locks, pipe wrenches, and chain wrenches. I’ve also heard the refrain “much easier with the proper tool” but no reference to the proper tool.
 
Oct 24, 2010
2,405
Hunter 30 Everett, WA
I've used the same as you mention. Then I changed to a PSS. It was a pain getting the flange off to do this, but my stuffing box had to be replaced anyway. A dripless shaft seal was almost the same cost.
 
Jan 4, 2013
279
Catalina 270 Rochester, NY
I purchased an open end wrench 1 7/8" from Amazon that fits my box perfectly and use a small pipe wrench also to hold the main nut while using the box wrench to tighten the lock nut.
 

jssailem

SBO Weather and Forecasting Forum Jim & John
Oct 22, 2014
22,217
CAL 35 Cruiser #21 moored EVERETT WA
I’ve also heard the refrain “much easier with the proper tool” but no reference to the proper tool.
Perhaps because we all have different configurations of the same stuffing box system. How your boat is designed, the access (room to work), influences the best tool for you.

I use the above tools. Most helpful in my boat is the plumbers straight wrench.
1625322625895.png
 
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Feb 10, 2004
4,069
Hunter 40.5 Warwick, RI
Two fixed size wrenches (I can't recall the proper name) are best. Nothing to adjust and large flat surfaces that will engage the nuts without slipping.
Having said that, I use two 24" adjustable wrenches from Harbor Freight. The 24" length gives lots of leverage. I always had leverage issues with the straight wrench that is pictured above.
2016_0614_134102.JPG
 
Dec 25, 2000
5,863
Hunter Passage 42 Shelter Bay, WA
What works best on our boat is this Service Wrench of the proper size: https://www.amazon.com/Wright-Tool-...words=service+wrenches&qid=1625326703&sr=8-44

I've tried all the others mentioned so far and they have not worked. I use a piece of SS tubing crimped on one end to slide over the handle to provide additional leverage when needed. Our stuffing box requires two different sizes; one size for the box, a separate size for the lock nut. Also, I add some anti seize compound to the threads and lock nut face in order to prevent them from seizing up over time.
 
Jan 7, 2011
5,250
Oday 322 East Chicago, IN
It depends on your stuffing box…flat sided nuts can easily be adjusted with the plumbers wrench that @jssailem referenced.

but my stuffing box does not have a flat sided nut…
0B5A32EA-CFE2-46CD-A992-820D121D3123.jpeg
so that wrench is pretty useless to me.

I use a small pipe wrench or a pair of channel locks.
So, yes size matters, but also the right tool for the job, which in this case means for the specific stuffing box nut you have.


Greg
 
Dec 25, 2000
5,863
Hunter Passage 42 Shelter Bay, WA
Here's the bible on stuffing box maintenance include wrenches
Not my bible when it comes to wrenches. The two referenced, pipe and adjustable, which I have tried and they failed, have to be the poorest choice when it comes to tools. Over time, pipe wrenches round off the flats and the adjustable ones tend to flex. A Service Wrench of the correct size is your better choice. There is an upside to having the better tools for your boat.
 
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May 28, 2015
280
Catalina 385 Atlantic Highlands, NJ
Does 2.25” make sense as a standard size for a 2016 Yanmar 3JH5E on a Catalina 385 and if so can you buy open wrenches at that size?

I’ve succeeded with the adjustable wrenches but I want to get the right size open wrench. I just measured the inside of the adjustable set to fit.
 
Feb 26, 2004
22,901
Catalina 34 224 Maple Bay, BC, Canada
After too long suffering with the tools Terry mentioned, I went to a tool shop, bought the right size for my lock nut and had the tools shop cut it in half. Works great. I still use the adjustable on the box itself which turns easily once the lock nut is backed off. Photo shows the cut long combo wrench and the old fixed jaw which never seemed to fit the lock nut.

IMG_20180613_124743 (Small).jpg
 
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Jul 19, 2013
387
Pearson 31-2 Boston
Not my bible when it comes to wrenches. The two referenced, pipe and adjustable, which I have tried and they failed, have to be the poorest choice when it comes tools. Over time, pipe wrenches round off the flats and the adjustable ones tend to flex. A Service Wrench of the correct size is your better choice. There is an upside to having the better tools for your boat.
From the referenced article:
"TIP: While I show these wrenches as wrenches you can use I would urge you to purchase as set of proper stuffing box wrenches for your particular box. Buck Algonquin and others sell packing box wrenches and they can be purchased from vendors such as Hamilton Marine."
 
Jun 11, 2004
1,700
Oday 31 Redondo Beach
It depends on your stuffing box…flat sided nuts can easily be adjusted with the plumbers wrench that @jssailem referenced.

but my stuffing box does not have a flat sided nut…
View attachment 195830
so that wrench is pretty useless to me.

I use a small pipe wrench or a pair of channel locks.
So, yes size matters, but also the right tool for the job, which in this case means for the specific stuffing box nut you have.


Greg
It will certainly depend on your access and type of nuts. Mine are like Tally Ho's and packing gland wrenches, plumbers wrenches and regular open end wrenches don't work well for me. I use two small pipe wrenches.
 
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Nov 22, 2011
1,227
Ericson 26-2 San Pedro, CA
After too long suffering with the tools Terry mentioned, I went to a tool shop, bought the right size for my lock nut and had the tools shop cut it in half. Works great. I still use the adjustable on the box itself which turns easily once the lock nut is backed off. Photo shows the cut long combo wrench and the old fixed jaw which never seemed to fit the lock nut.

View attachment 195836
Stu is 100% correct. Having the correctly sized open end wrenches is the only way to go. Those adjustable plumbers' wrenches that you get from places like Home Depot are especially useless.
 

Sailm8

.
Feb 21, 2008
1,747
Hunter 29.5 Punta Gorda
I always end up soaking the lock nut with bp blaster for a few days and then placing a big screw driver against the nut and wacking it to get it loose enough to turn. THEN I start rotating through my collection of wrenches to make the adjustment.
 
May 28, 2015
280
Catalina 385 Atlantic Highlands, NJ
I always end up soaking the lock nut with bp blaster for a few days and then placing a big screw driver against the nut and wacking it to get it loose enough to turn. THEN I start rotating through my collection of wrenches to make the adjustment.
This sounds very familiar (except the banging on screwdriver), hence why I asked about the 2.25” wrenches. After this latest episode, I want to have the right tools onboard and exercise and lubricate the lock nut when I exercise my thru-hulls
 
Jun 25, 2004
479
Hunter 306 Pasadena MD
I bought the following from Amazon last year: it's great if you have limited room:
ares_wrench.jpg
It's the ARES 70303 - 53mm Stubby Adjustable Wrench:
This is a really nicely machined adjustable that I use on the thin lock nut. I hated the cheap pot-metal plumber's wrenches. Still need a really big one for the large (non-lock) nut: that's on my to-buy list.
 
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