Stuffing Box Bolts

[ThirdHatt]

Well after a nice weekend on the boat only a short couple of hours (total) of cruising behind me I have found an interesting problem. Once I was back at the dock I did my post-cruise engine room checks and noticed a pretty good stream of water coming from both shaft logs. No problem I thought, I'd just grab my 15/16" and snug them up. Although I have done this a few times on the port, I had never had to on the stbd until now. Well, the port stopped it's stream quickly, as anticipated with just a 1/4-1/2 turn of each nut.

I then went to the stbd and noticed that there were two nuts on each side, one regular size and a smaller, lock nut. Hmm, different but no problem, right? I loosen the inboard lock nut and proceed to tighten the larger nut a couple of 1/4 turns. Then to keep proper alignment I move to the other side. I loosen the lock nut and begin to tighten the main nut and although fairly tight at first, it gets easier, then REAL EASY! Oh no, I know that feeling! I stopped immediately to re-acess. SOMETHING was letting go. I wondered if the bolt was letting go from the back side that I cannot see and pulling out. I swapped my deep socket for a wrench and nope, bolt not turning. Hmmm. Loosen nut several turns and it comes back fine, tighten up and it gets to the plate and looses torque. Finally I decide to loosen the nut considerably and low and behold the threads are STRIPPED for about the width of the larger nut! OH NO! Now I take a look back at the port side only to realize that the port has STAINLESS bolts and nuts, whereas the stbd side that is giving me trouble is BRONZE! Okay, so the port must have experienced this problem in the past and was upgraded to SS, but I guess it's my turn to to the stbd!

So, how the heck do you get to the backside of these bolts? They are right under the massive raw water strainer and I cannot see behind the plate. I called my local wrench (great guy that I don't hire NEARLY enough to learn from b/c I always try to do it all myself ) and he suggested that they are not bolts, but studs and that I should be able to back them out and replace with SS studs. WOW, sure sounds easy, but we all know that chances are it won't quite happen that way.

Anyone run into this problem before? Any suggestions before I marr the threads on the end trying to back the stud out (if it IS a stud)?

Thanks in advance to any suggestions.

 

[SKYCHENEY]

If you have alot of thread left above the stripped section, you could just add a spacer of some sort so that the nut rides on the good threads. This would at least get you by until a permanent solution is found.

 

[MikeP]

Although I can't say for sure, they are probably studs. You should look carefully at this before proceeding.

In theory it's simple enough - double nut the stud and unscrew it. Double-nutting allows you to turn the stud without damaging the threads (any worse than they are) HOWEVER - it is not at all uncommon to break a stud trying to remove it. Since you are in the water, this is probably not the best time to fool with that particular stud. If you break it, you have a real operational problem instead of an annoyance.

If I properly understand the description of the situation, you could continue to use it as is - just put another spacer under the nut to keep the nut in the threaded area. This would be a lot safer until the boat is out of the water.

If you elect to fool with it, BE CAREFUL - since it is brass/bronze, it will shear very easily compared with a steel bolt. And think about the worst case - if you shear it off, can you get a drill into position to drill the stud out WHILE water is dribbling (or worse) all over the place? If the answer is "no," I wouldn't try to pull it with the boat in the water. Also, after you drill it out, you would need a helicoil kit to rethread the fitting for a new stud.

But hopefully the stud will twist right out with little effort.

Good Luck!

 

[Genesis]

They're studs, and bronze, and they erode over time due to vibration - they're not stripping per-se.

If you can put a couple of washers under the nut, you can continue to tighten it down for a bit, which will handle it for now.

Double nut it if you want it out and use a lot of PB and Patience. If it won't come, don't get greedy - hit it AGAIN and wait.

If you break off one of the studs in the water you're in trouble - so you may want to wait for the next haul to actually fix this. You can washer this easily enough until then. The studs themselves are cheap.

BTW, if you have SS on the other side, you should remove them and replace with Bronze. You don't want the stuffing box parts getting eaten - and SS is the more noble.

 

[Pascal]

yep... got a few stripped threads on the port box. I added an extra nut so that the one that compress is on good thread. not taking chance with that in water, just in case....

 

[ThirdHatt]

Wow. Decisions, decisions. I agree that the spacer thing may be the best way to go for the time being. I hate putting stuff like this off, although I do tend to err on the side of safety. I may try to get some PB on the back side of the stud if I can reach it, let it sit overnight and then try to apply a little torque to the double-nut and see if it comes out easily (HA!). If not, I'll just snug it as best I can until the next haul-out which should be in about 6 months.

Pascal, you are making me feel better knowing that I am not the only one!

Karl, Thank you for confirming that they are studs. Now I know that I can get them out from the front. unfortunately, now you are telling me to remove the nice, strong-looking SS ones on the port! OH NO! I know it's the right thing to do, I guess I just needed to hear it. BUMMER!

Thank you to all who responded. This forum has done it again!