Leak around propeller shaft

[Mike Everett]

Our new 1978 CD 28 "Dr. Pepper" is our very first inboard engine, and therefore our first through-hull propeller shaft. We lauched late this year, about a month ago. I've noticed that the leak through the stuffing box is a (estimated) half-gallon per hour after the engine has been running, and about a drip per second after the boat has been moored for a week. So far the automatic pump plus solar panel has been able to keep up with the problem when we leave the boat.
The previous owner told me that the stuffing box is locked with two nuts, and can be adjusted, so armed with this advice I crawled into the cockpit locker and found what I assume is a stuffing box, which is the through-hull fitting perhaps 1 and 1/2 inches thick around the propeller shaft. Am I right about this?
Next problem was that my two 3/4 inch crescent wrenches wouldn't fit on the (presumed) stuffing box for two reasons: 1 -- It's thicker than 3/4 inch and -- 2 -- the the V-shaped space in which the fitting sits is too narrow to accomodate any wrench I've ever seen.
So questions are -- How serious is the leak? Is there some nifty tool I can obtain to fix it? Do I need professional help? Any ideas will be gratefully appreciated.
By the way, we had a great sailing day yesterday: while on a tack east of Seguin Island, we were overtaken first by a CD 30 (Chinook out of Bath), and then by a CD 36 (didn't see the transom), so we had 3 CD's sailing the same tack together. Beautiful sailing craft. It was pretty impressive.



everett@megalink.net

[Matt Cawthorne]

Mike,
If you have the same stuffing box as most other CD's then Spartan marine makes special wrenches for the stuffing box and sells them at a special price. Some people use a drift punch to loosen the nuts, but I prefer to buy the wrenches. You will find many opinions about how much a stuffing box should leak. I am on the side of not letting it leak very much. Try using the search button on this web page. There are many discussions on the subject. Adjusting the stuffing box is a simple job that can be mastered by anyone who is willing to ask questions when something doesn't seem right and crawl into a cockpit locker. Don't overtighten the stuffing box. The major point of discussion is what each of us considers tight.
Enjoy your boat.
Matt

Our new 1978 CD 28 "Dr. Pepper" is our very first inboard engine, and therefore our first through-hull propeller shaft. We lauched late this year, about a month ago. I've noticed that the leak through the stuffing box is a (estimated) half-gallon per hour after the engine has been running, and about a drip per second after the boat has been moored for a week. So far the automatic pump plus solar panel has been able to keep up with the problem when we leave the boat.
The previous owner told me that the stuffing box is locked with two nuts, and can be adjusted, so armed with this advice I crawled into the cockpit locker and found what I assume is a stuffing box, which is the through-hull fitting perhaps 1 and 1/2 inches thick around the propeller shaft. Am I right about this?
Next problem was that my two 3/4 inch crescent wrenches wouldn't fit on the (presumed) stuffing box for two reasons: 1 -- It's thicker than 3/4 inch and -- 2 -- the the V-shaped space in which the fitting sits is too narrow to accomodate any wrench I've ever seen.
So questions are -- How serious is the leak? Is there some nifty tool I can obtain to fix it? Do I need professional help? Any ideas will be gratefully appreciated.
By the way, we had a great sailing day yesterday: while on a tack east of Seguin Island, we were overtaken first by a CD 30 (Chinook out of Bath), and then by a CD 36 (didn't see the transom), so we had 3 CD's sailing the same tack together. Beautiful sailing craft. It was pretty impressive.

mcawthor@bellatlantic.net

[Mike Everett]

Thanks for the information. I've copied the previous posts on the subject (including yours) and I feel better educated now.
Lucky me, I can drive to Spartan Marine on my lunch hour!



everett@megalink.net

[Duncan Maio]

Lucky me, I can drive to Spartan Marine on my lunch hour!

Your local hardware store sells adjustable wrenches (they look like big, two-tined forks) for about nine bucks that will do the job. Of course, you need two - one for the lock nut, and the other for the stuffing box nut.

I adjusted the stuffing box on my CD27 last week in about 15 minutes - a little WD-40 on the box for several minutes before you start will help.

Much has been said about adjustment, drips per minute, etc. My feeling is that if the stuffing box is not warm after running for a while, it is not too tight. A drip or two a minute when running is a good sign.

-Duncan Maio
s/v Remedy



dmaio@worldnet.att.net

[denny]

I can't imagine getting any wrench around the packing nut and/or lock nut on the CD28. The space is much to limited. I always use and have used a heavy screw driver and small hammer to adjust the spined nuts. However, I've freed up the threads so that I can turn the nuts freely by hand and then well lubricated the threads with silicone or teflon grease. To free up your corroded threads apply medium grit water based valve lapping compound to the threads and work the nuts back and forth until the nuts glide freely. Then wash off all the compound thoroughly with water and lube up the threads. You can get lapping compound at an auto parts store.
You should leak about 5 to 10 drops per minute on the perfect packed gland with good shaft alignment. About half that when the engine is stopped and then 0 drops in a few hours as the packing swells up.
You will never get good packing performance unless the prop shaft coupling is aligned satisfactory with the transmission coupling. The problem you describe is classic shaft misalignment.



denny@nations.net

[denny]

I can't imagine getting any wrench around the packing nut and/or lock nut on the CD28. The space is much to limited. I always use and have used a heavy screw driver and small hammer to adjust the spined nuts. However, I've freed up the threads so that I can turn the nuts freely by hand and then well lubricated the threads with silicone or teflon grease. To free up your corroded threads apply medium grit water based valve lapping compound to the threads and work the nuts back and forth until the nuts glide freely. Then wash off all the compound thoroughly with water and lube up the threads. You can get the lapping compound at the auto parts store.
You should leak about 5 to 10 drops per minute on the perfect packed gland with good shaft alignment. About half that when the engine is stopped and then 0 drops in a few hours as the packing swells up.
You will never get good packing performance unless the prop shaft coupling is aligned satisfactory with the transmission coupling. The problem you describe is classic shaft misalignment.

Our new 1978 CD 28 "Dr. Pepper" is our very first inboard engine, and therefore our first through-hull propeller shaft. We lauched late this year, about a month ago. I've noticed that the leak through the stuffing box is a (estimated) half-gallon per hour after the engine has been running, and about a drip per second after the boat has been moored for a week. So far the automatic pump plus solar panel has been able to keep up with the problem when we leave the boat.
The previous owner told me that the stuffing box is locked with two nuts, and can be adjusted, so armed with this advice I crawled into the cockpit locker and found what I assume is a stuffing box, which is the through-hull fitting perhaps 1 and 1/2 inches thick around the propeller shaft. Am I right about this?
Next problem was that my two 3/4 inch crescent wrenches wouldn't fit on the (presumed) stuffing box for two reasons: 1 -- It's thicker than 3/4 inch and -- 2 -- the the V-shaped space in which the fitting sits is too narrow to accomodate any wrench I've ever seen.
So questions are -- How serious is the leak? Is there some nifty tool I can obtain to fix it? Do I need professional help? Any ideas will be gratefully appreciated.
By the way, we had a great sailing day yesterday: while on a tack east of Seguin Island, we were overtaken first by a CD 30 (Chinook out of Bath), and then by a CD 36 (didn't see the transom), so we had 3 CD's sailing the same tack together. Beautiful sailing craft. It was pretty impressive.

denny@nations.net

[Paul Grecay]

I also have a CD 28 and this year I tightened the stuffing box. To answer your questions, yes, the two thin hexagonal nuts are the place to tighten up the stuffing. First you need to back off the one which is most forward (the one which holds the other in place). This will require turning it counterclockwise (as viewed head on from the front) Then turn the most aft nut clockwise to tighten it. Don't tighten too much...a little goes a long way...probably about a quarter to a half turn will be sufficient. The shaft should drip about one drop per minute with the shaft turning ... in other words, the shaft just needs to be wet. After tightening, check it by hand...make sure you can easily turn the shaft with your hand. If you have clamped down on the shaft, the thing will heat up, wear the shaft, and/or eat up the flax stuffing. You need to get the right wrenches...you need two of them and they are thinner and shaped differently than crescent style wrenches. The correct wrenches will work just fine. After several years of no adjustment, mine was a cinch to turn and adjust...took all of 10 minutes. I think I bought the wrenches at boat/us or west marine...can't remember, but they were cheap and I didn't have to special order them from spartan. My bilge pump is much less stressed since adjusting the stuffing box. Hope this helps.

Paul



rfurman@dmv.com

[Mike Everett]

Thanks to everyone who took the time to reply to my beginner's questions about my leaky stuffing box. I've learned a lot, both about theory and practice! You've earned the gratitude of the crew of s/v Dr. Pepper.
It's amazing to me how a good bulletin board like this one can contribute to the confidence and economy of a dubber such as I; imagine how much I could have spent - and how much less I would have learned - by taking my problem to a boatyard.
Thanks again.



everett@megalink.net

[RLMeigel]

So is the problem cleared up?



rlmeigel@aol.com

[Mike Everett]

So is the problem cleared up?

Hmmm, is that a loaded question?
If the problem is "Do I think I know what I'm doing and have I found the right tools to do the job?" the answer is Yes.
If the problem is "Have I returned to Dr. Pepper and fixed the leak yet?" the answer is No.
Here's what I'll do. Whether I'm successful or not this week-end, I'll report back. Watch this space!



everett@megalink.net

[Mike Everett]

So is the problem cleared up?

Hmmm, is that a loaded question?
If the problem is "Do I think I know what I'm doing and have I found the right tools to do the job?" the answer is Yes.
If the problem is "Have I returned to Dr. Pepper and fixed the leak yet?" the answer is No.
Here's what I'll do. Whether I'm successful or not this week-end, I'll report back. Watch this space!



everett@megalink.net

[Mike Everett]

I said I'd report back and here I am. So I'm back from Christmas Cove and I'm happy to say that Dr. Pepper's stuffing box is no longer leaking.
It took me longer than a few minutes, but then, a little adversity is a good thing.
My first problem was that the two adjustable stuffing box wrenches I got from West Marine were useless. The tines just wouldn't fit between the stuffing box nuts and the hull. Of course, it took me a while to figure this out.
So for the benefit of those rare souls who are even more ignorant of Cape Dory maintenance than I (hard to imagine, I know) not every wrench that's advertised as a suitable stuffing box wrench will work.
As you read this, those adjustable wrenches are on their way back to West Marine.
Having discovered that my tools just didn't work, I did what any guy hates to do -- I asked for help. I rowed over to the tool shed of Coveside Marine (where Dr. Pepper is moored) and by a fortuitous chain of events received the advice



everett@megalink.net

[Mike Everett]

of an experienced stuffing box tightener, who claimed, as proof, to have a bad back as the result of fixing up a Catalina 25, which he said has a stuffing box set in one of the higher levels of Hell. He lent me an offset adjustable wrench, the tine of which was hook-shaped and which fit -- just barely -- around the packing nut. With just a nudge, the packing nut came free of the locking nut, which I could then turn by hand. And so I adjusted as per advice, stopping the drip while ensuring that the prop shaft could rotate freely.
The Atlantic is no longer pouring into Dr. Pepper's bilge, and her crew can worry about other things.
A few things I've learned: One, the wrenches and stuffing boxes presently manufactured by Spartan Marine are quite different from the one on my 1978 Cape Dory. Specifically, the newer nuts are circular and have lugs, as opposed to the older flat-side octagonal nuts. It seems that the new Spartan wrenches wouldn't fit the older stuffing box nuts. Second, using



everett@megalink.net