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Old 05-08-2013
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Re: Hot stuffing box...

Thanks for all the replies so far. I'll try and provide more useful information....


I didn't stand over them when they packed it, but I DID interrogate the yard worker personally who did the work. He told me that he was able to get all the stuffing of differing diameters out of there easily when the prop shaft was out. He was able to see that the portion you pack, which is where the bronze packing gland and nut are threaded to a stainless tube (instead of the usual hose) there was a LOT of room for packing.

He told me that the packing was 1/4" diameter, and that he thought long and hard about 11 or 12 strands but decided I'd probably need the extra adjustment and went for 12. He tells me that these things almost always take 3 or 4 strands and he's never seen one quite like mine. Off the top of his head he remembered that the strands were each 5 3/4" each and that he used about 70" of packing total.

These guys, by the way, are the former yard mechanics of Bayliner/Maridian. When Bayliner went out of business they all followed their old yard boss to the new yard in Anacortes. They really do seem like a competent bunch, and this isn't my first time in the yard.

So I take them at their word that there's 12 strands in there. I was CONSTANTLY adding more and more strands to my ever-leaking nut wondering where they heck they were going.

I was surprised (and a little skeptical) of their choice of flax. They said that they've seen the graphite get hot and gouge the deepest grooves in shafts. They said the PTFE/Teflon stuff was what they used for a while but it got really really hard after a while and stopped working. They found that in the end flax was the most forgiving.

Now, with all that, how hot is too hot? I agree about using the thermal IR gun. I can borrow a crappy one, and have been needing an excuse to buy one. What temp is okay?

Also, I feel that all bets are off for the "standard rules of thumb" for how many drips per second/minute. If "X" number of drips keeps 4 strands cool, how many does it take to keep 12 cool?

Another piece of info, is that the stuffing box has never been hot before. I apparently had all kinds of crap mashed in there, (all the stuff I put in was teflon) and the shaft was wobbling around so much that maybe it never built up friction because it never fit, but it's never ever been hot before.

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