Stuffing Box Always Hot

[Chief Engineer]

Originally Posted by Beausoleil

FWIW - invest in an IR laser thermometer - they're as cheap as $US30 or even less. I've verified that my stuffing box, after running for hours, is a cool 89.8°F when the water temp is about 68°F. And virtually no drips, even without Teflon or Goretex packing...

Thos IR thermometers can be used for a number of things...I have a small Raytek........wonderful diagnostic tool

[shakey doug]

A well set up gland will run between 100f - 150f oil filled gyler gear to 165f ,greasy hemp or teflon bedded slowly over a 1-2 hr period will give the best service. A stern gland -tube over greased will cause over heating a mistake a lot make.If burning ocurrs remove immediately otherwise you have a lathe tool .If gland --bearing has a lanturn ring fitted angle cut packing--shaft dia + packing thickness x 3.14 = length then lightly flattern with hammer before stagger fitting.

[TOM]

Thanks for all the advice .This has been a very frustrating and stressful problem especially after spending so much money on a repower . The problem was simply that after repacking the stuffing box {with the shaft disconnected from the v drive hense loose} i replaced the flange of the stuffing box UPSIDE DOWN! .The reason i was able to do so was because the shaft was loose .

We have basically run in our new Yanmar at between 2700rpm and 3200rpm {as per manuel} for 50 hours with an upside down stuffing box . Inspection shows that we have incurred some shaft damage but very minor.The only reason i found the problem was because i thought i had put too much grease in th SB so i pulled it out to scoop the excess grease out . Then i found i could not push it in again except if i turned it upside down.

Now before you all think iam completely stupid i want to say that the flange looks almost identical either way up.

What is most embarassing is that at the start of this problem my wife said "Honey do you think it might be upside down ? . I said no thats impossible .

NEW RULE .... Nothing gets touched on this boat until it gets photographed first {thank god for digital}

And i need to start listening to the 2ic.

[karlhead]

Don't feel bad. How many years of experience are represented here trying to fix your problem? Seems we all try to make things too complicated.

[Cheechako]

"i replaced the flange of the stuffing box UPSIDE DOWN!" I dont get it... your stuffing box doesnt clamp to a rubber tube? I've never heard of an orientation for a stuffing box, and cant visualize why one would matter... even one with a two bolt flange could go 180 degrees out without an issue couldnt it? I'd like to learn from this but... can get it in my head....

[karlhead]

I don't understand either but he said it's fixed. I would like to see some pics. Perhaps an old dog can learn new tricks.

[shakey doug]

IF you pour to much grease into gland-tube you will get over heating ,packed glands should not run any hotter than 150f greasy hemp or teflon best packing do not use
graphite on s/s shafts use angle cut packing unless gland is fitted with a lantern ring. Shaft dia + packing thickness x 3.14 = length, lightely flatten packing before installation .

[gettinthere]

I have an IR temp gun. The packing gland only gets 2 degrees hotter than the nearby hull after a long day of running. 150d seems HOT.

[lorenzo b]

My stuffing box was running to hot to leave my hand on and I was told that the only cause could be metal on metal contact. The yard sent over a mechanic since they had just installed it and indeed the box was improperly aligned.

[nhschneider]

One statement that I noticed was that the prop shaft was running without vibration and therefore it was presumed to be in proper alignment. Coupling alignment is best completed by using a set of feeler gauges. Many consider .004" to be the maximum for a coupling to be out of alignment. A prop shaft could have more than that and visually appear to be running true.

[delmarrey]

Originally Posted by nhschneider

One statement that I noticed was that the prop shaft was running without vibration and therefore it was presumed to be in proper alignment. Coupling alignment is best completed by using a set of feeler gauges. Many consider .004" to be the maximum for a coupling to be out of alignment. A prop shaft could have more than that and visually appear to be running true.

In response to this, boats flex as they go through seaways, or even weather changes can cause alignment problems. This is why it's a good reason the use up-to-date flexable shaft couplers. Especially with diesels that tend to viberate & shake a lot. No matter how close you get it in port, once you start up the motor and moving around it'll change. And the smaller the boat the worse it is.

R and D MARINE : Flexible Shaft Couplings