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Capital Newport Mk ii
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Discussion Starter · #1 ·
Noticed excessive stuffing box leak. Old flax, so decided to change it vs tighten. Never did it before. Seemed straight forward. Read all old posts everywhere including MaineSail's regarding this subject. Newport 30ii, 1977. 7/8" shaft. 1/4"+ space between shaft and gland nut. Old flax was in bad shape and appeared to be 3/16". Replaced flax with 1/4" while in the slip. Was unable to get drips correct. Could get lots of drips or no drips. At one point I had 5-8 drops per minute, in slip, engine in forward, so i did a 30 min test run out of slip. Appeared to have 0 drips and gland nut got HOT to touch. Back in slip, i disconnected the gland nut and had zero water intrusion for a couple of hours; then the water started trickleing in! What would cause temporary water stoppage? Started over from scratch. New, same 1/4" size flax, but with SynTef. Bought cheap IR temp instrument. Made extremely small (3-5mm) nut adjustments until I got close to suggested drip. Began with 1-2 drops per second with engine off. Made static adjustment to yield one drop per 45 seconds. Let it sit for 2 hours. Did short test run out of slip. Static and in-gear drip was excessive (did not record). Made small adjustments. Nut temp 75. Started engine, 800 rpm, neutral, drip was 1 drop per 4-6 seconds and the same when in forward which seemed reasonable; IR temp was 110-118 (warm to touch). Made no nut adjustment. Increased rpm to 1600 in forward (tied in slip). Had no drips for next two minutes and IR temp rose to 145 (hot to touch). At idle rpm drip returned to one drop per 3-5 seconds and IR was 118. In reverse at idle, drip increased to one drop per second and the IR was 125. Still in reverse, rpm at 1600, drip was 1-2 per second, IR 145 (hot to touch). During the next 20 minutes, without making any nut adjustments, at idle power, in neutral and forward, the drips remained in the one drop per 3-5 second range with IR 125-130. Increasing rpm to 1200 in forward yielded zero drip and IR went to 150 (hot to touch). What could cause the higher rpm to cause the loss of dripping water and higher nut temperature? I did not see evidence of water being spun off the shaft. I am considering loosening the nut to let in more water to hopefully get lower IR temps at normal operating rpm; also considering having the shaft, motor mounts and engine alignment checked, but the maintenance facilities are pretty busy now. Am I missing something? Suggestions?
 

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Craig.

Strange symptoms indeed.
With shaft spinning, I would loosen it until it ran wet, and let it run wet on a long (dockside) run in gear.
Make sure that the boat is well tied to more than one bollard aft.
Then slowly tighten the packing nut until it just runs wet with shaft spinning.

I trust that you packed the shaft with the standard idea of using multiple horse-shoe elements?

Don't let it run hot for long. It will murder the shaft.
 

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Discussion Starter · #3 ·
Rockter, Thank you for the suggestion. I did use the standard horseshoe with three elements. Your idea sounds reasonable, but risky. I will try loosening today, but i am not willing to make an adjustment to the spinning shaft, if that was your meaning. With the lock nut unlocked, the spinning shaft can cause the gland nut to spin to full loose and loosening both nuts with the shaft spinning puts my fingers at risk. I will loosen both nuts while engine is running (in neutral) to increase the static leak, then check it while spinning with fingers clear. I have had some initial success doing that until the rpm is advanced above idle which causes the water drip to stop and the temperature to increase. Unfortunately, at that point, i will be repeating what has not yet been successful. The big question seems to be: how/why does the increased rpm stop the water flow out of the gland nut? I welcome all ideas.
 

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Is the flax sitting flush and are the diagonal cuts in each of the layers offset from all other layers? Was the stuffing box cleaned of all old flax? Are you using the teflon flax? was replacing the flax a tight fit?It sounds like it may be moving about in there…
 

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Discussion Starter · #6 ·
Itsaguything. Good questions. Offset yes. Flax cut at 45 degree angle and placed 120 degrees apart. Fit seemed good. Space between shaft and gland nut is just a hair over 1/4”; used 1/4” non-teflon flax and seemed a snug fit. I believe i got all old flax out.

Today: Loosened gland nut completely, but not off the threads. Had steady 2-3 drips per second. Tightened gland nut incrementally by flats to achieve 1-1.5 drips per second. “Locked” lock nut. Started engine. At idle neutral had fast 3-4 drips per second. In forward had no drip until my lock nut loosened sending the gland nut forwand and spraying water sideways. Retightened gland nut to the locknut position plus additional flats and locked it. Engine off, 2 drops per second. Engine on, idle and forward 2-3 drops per second IR temp 90F. Tightened gland 3 flats. With engine on, idle, neutral, 1drop per 2-3 seconds. IR 90F. Increased rpm to 1200, forward, had 1drop per 3 seconds; IR went to 114,127, 138F; but could hold finger on hot gland nut. Drip slowed to 1 per 6 seconds but IR went to 153F, but despite being rather hot I could still hold my finger on the nut.

Three hours have passed. Engine cool. Gland nut 69-77F. Static drip engine off is 1drop per 8-9 seconds. Engine on, idle, neutral, 1drp 6-9 seconds, IR 87. Engine at1400 rpm, 1 drop per 6 seconds, IR 128, nut warm to touch. Two minutes later, same drip, IR 137F hot to touch. Two more minutes IR 145F hot to touch, but can keep finger on nut. One more minute IR at 160 Hot (probably can’t keep finger on nut). Back to idle. Drip stayed at 1 drip per 5-6 seconds which should have kept the shaft cool. Over the next 15 minutes with engine idle and forward, drip slowed to 1 drip per 2-3 seconds and IR lowered to 130F. Ten more minutes IR 98F, 1 drip per 6 seconds.

I wonder what the highest temperature a finger can take without burning! Today i have drippage that should cool the gland nut, but doesn’t! Should i be measuring the exposed shaft temperature instead of the gland nut?

Please excuse the length of this post.
 

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Craig.

Strange symptoms indeed.
With shaft spinning, I would loosen it until it ran wet, and let it run wet on a long (dockside) run in gear.
Make sure that the boat is well tied to more than one bollard aft.
Then slowly tighten the packing nut until it just runs wet with shaft spinning.

I trust that you packed the shaft with the standard idea of using multiple horse-shoe elements?
 

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Yep, its getting too hot. I suspect the metal housing is expanding with the temperature increase.

So, replace with a smaller flax. The idea is to keep the box wet. The water acts as a lubricant and a coolant. There should not be so much friction that she gets hot.
 

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Discussion Starter · #10 ·
Thanks for continued input. I will replace the 1/4 with 3/16. I bought both when i started. Chose the 1/4 due to the shaft and ‘head’ space measurements, and the poor condition of the prior flax that appeared to be 3/16.

Any thoughts regarding using Syn Tef on the flax as suggested on the flax package? Used it on the current flax which appeared to generate a large amount of messy black crud within the drips coming from the gland nut.
 

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I get 10+ years out of Graphtex Utlra Packing BUT every year as part of spring commissioning, I back the packing nut off, clean the exposed part of the shaft and then apply about a tablespoon's worth of Teflon Grease. I have been using Finish Line Teflon Grease for years for this. I then tighten the packing nut just hand tight. After a few weeks in the water, I adjust it so it only drips one or two drops occasionally when motoring. When not motoring, it never drips. Pay attention to your shaft log and make sure it is not cracked. If so, replace with proper shaft log hose which is different and much stronger than standard hose.
 

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Discussion Starter · #12 ·
Thank you for the input.

Yesterday I removed the 3 rings of 1/4” flax that was installed 2 weeks ago. Took 9 hours to dig it out. Was very tight, solid, and actually hard to “find”. This morning I installed 3 rings of 3/16” of standard flax shaft packing. Since i seemed to have additional room, i added a 4th ring. Used Syn Tef on the packing per package instructions. Have tightened gland nut about 2-3 turns. Drip is currently about 2 per second. Have not started the engine. Not sure if i should let it drip like this for awhile, or tighten it more to slow the drip. Seems there are varying opinions regarding tightening. Not in a hurry.
 

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Thank you for the input.

Yesterday I removed the 3 rings of 1/4” flax that was installed 2 weeks ago. Took 9 hours to dig it out. Was very tight, solid, and actually hard to “find”. This morning I installed 3 rings of 3/16” of standard flax shaft packing. Since i seemed to have additional room, i added a 4th ring. Used Syn Tef on the packing per package instructions. Have tightened gland nut about 2-3 turns. Drip is currently about 2 per second. Have not started the engine. Not sure if i should let it drip like this for awhile, or tighten it more to slow the drip. Seems there are varying opinions regarding tightening. Not in a hurry.
Yes, many have many opinions. She should “swell” on her own. It would be interesting to know if she settles down on her own, too. Give it a couple of days. I let mine drip 2-3 times a minute while underway... there is no drip otherwise. No overheating and no wet mess.
 

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Discussion Starter · #14 ·
I let it rest about 3 hours. Static, about 1-3 drops per second. Started it. Let it run for 90 minutes, at idle in neutral, and in forward at idle, 1200, 1500, 1800 rpm. Temperature never got above 100. There were no drops; just a small waterfall of cooling water bathing the shaft and nut. I made no nut adjustments. Just put it to bed for the night. Three weeks ago i thought this was going to be a “by the numbers” event, but it appears to be more of a “teething” development. I hope that as i reduce the water flow, the temperature will remain cool. Since i have an abundance of water flow, I am inclined to tighten the nut a couple of flats incrementally and then go motor around for an hour or two to watch it.

My biggest surprise so far, is that the hype for not doing this in the water was overblown, at least for my setup. I had only a slow trickle that made it easy to work slowly.
 

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Discussion Starter · #16 ·
Today: engine off static drip 1drip per second. Shaft/nut 73 degrees F. Hand tightened gland nut 4 flats. Drip increased to 3 per second. (This is not an error.) Started engine and ran for an hour in slip.

Experimented with numerous settings. Set idle, 1500, 1800, 2000, 2400 rpm in forward. Temperature never exceeded 110 for nut or 106 for shaft. Had excessive water drip.

At idle, forward, drips were fast at 3-5 per second. At 1500-2400 drips slowed, but cycled between fast to slow to zero and repeated. For example : 3-5 per second, then 8 per minute, then gradually back to 3-5 per second. Could there be air in the system that affects the water flow?

Shut down engine. Static drip steadied at 40 per minute. I tightened the nut 1/2 flat. Ran engine for 35 minutes with about the same results. Cool temps and cycling water flow.

I will run it again tomorrow and will expect to tighten the nut some more.
 

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Today: engine off static drip 1drip per second. Shaft/nut 73 degrees F. Hand tightened gland nut 4 flats. Drip increased to 3 per second. (This is not an error.) Started engine and ran for an hour in slip.

Experimented with numerous settings. Set idle, 1500, 1800, 2000, 2400 rpm in forward. Temperature never exceeded 110 for nut or 106 for shaft. Had excessive water drip.

At idle, forward, drips were fast at 3-5 per second. At 1500-2400 drips slowed, but cycled between fast to slow to zero and repeated. For example : 3-5 per second, then 8 per minute, then gradually back to 3-5 per second. Could there be air in the system that affects the water flow?

Shut down engine. Static drip steadied at 40 per minute. I tightened the nut 1/2 flat. Ran engine for 35 minutes with about the same results. Cool temps and cycling water flow.

I will run it again tomorrow and will expect to tighten the nut some more.
@craigarey, Hope the threads are clean. Give a shot of WD-40 or lithium grease to lubricate the threads. Then, tighten it until you feel the packing on the nut. Lets get that rate of drip down.
 

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Discussion Starter · #18 · (Edited)
Today: engine off static drip 1drip per second. Shaft/nut 73 degrees F. Tightened gland nut 4 flats. Drip increased to 3 per second. Started engine and ran for an hour in slip.

Experimented with numerous settings. Set idle, 1500, 1800, 2000, 2400 rpm in forward. Temperature never exceeded 110 for nut or 106 for shaft. Had excessive water drip.

At idle, forward, drips were fast at 3-5 per second. At 1500-2400 drips slowed, but cycled between fast to slow to zero and repeated. For example : 3-5 per second, then 8 per minute, then gradually back to 3-5 per second. Could there be air in the system that affects the water flow.

Shut down engine. Static drip steadied at 40 per minute. I tightened the nut 1/2 flat. Ran engine for 35 minutes with about the same results. That is, in forward at idle rpm, the drip is fast and steady. At operating higher rpm the drip rate slowly decreases to zero, remains there for a couple of minutes, then slowly climbs to a higher rate. What can cause such a cyclical change?

I will run it again tomorrow and will expect to tighten the nut some more.
 

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Discussion Starter · #20 ·
Itsaguything. After the first 2-3 turns of the packing nut yesterday, i could feel it contacting the flax. That’s why i have not tightened it much further. I thought i pushed the 4 flax rings all the way in. Perhaps I didn’t push them in completely. If they weren’t completely in, it seems like the spinning shaft could have dislodged the flax from their desired positioning. Would it be appropriate to disconnect the nut, inspect the flax and try to repush it forward?
 
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