Page 1 of 1

Shaft Packing

Posted: June 5th, 2020, 6:44 am
by Coastie78
Good morning, I am in the process of learning all about shaft packing. I was in the bilges of my 1985 3227 tightening my packing nut. I realized as I was wedged between the engines that this should have been something I looked at out of the water, lesson learned. I managed to get the flow of water cut in half. But I think I need to repack it correctly. I was wondering, before I went and bought a micrometer or some type of measuring gauge if any one knows the right size of packing for the 3227 with 1 1/4 shafts? Thanks in advance and for the many knowledgeable posts on this site.

Re: Shaft Packing

Posted: June 5th, 2020, 7:24 am
by Viper
Here are the standard sizes by shaft diameter

1" shaft = 1/4" packing
1 1/8" shaft = 3/16" packing
1 1/4" shaft = 1/4" packing
1 3/8" shaft = 5/16" packing
1 1/2" shaft = 1/4" packing
1 3/4" shaft = 1/2" packing
2" shaft = 3/8" packing
2 1/4" shaft = 7/16" packing
2 1/2" shaft = 5/16" packing
3" shaft = 9/16" packing

You can do this in the water, just cut your 3 pieces per shaft prior to removing the packing nut. To do this, cut one end of your new packing at a 45 degree angle, wrap the packing around an exposed area of shaft, and cut the packing at 45 degrees ensuring it butts up tight against the first end you cut. Make three of these per shaft. Make sure you use a new blade and let it do the work or you'll fray the ends, try to make as clean a cut as possible.

Have pick with little hook hook on the end, remove the nut and pick out all the old packing inside. You will get some water coming in but it'll be manageable. I like wrapping a rag around the shaft at the tube. Take each piece you cut and install them with the cuts offset from the previous one. I like putting them at 12, 4 and 8 o'clock then thread the nut back on.

Tighten the nut just enough until you get a steady drip, not stream. DO NOT over tighten. I like walking away for a day and allow the packing to get wet and expand. Then tighten the packing until you get a drip every couple of minutes. Then you need to revisit after a good run on the water. Dripping while running is normal.

Having a drip is normal with this type of system, it's what lubricates the contact area between the shaft and packing. If you tighten too much, this area will heat up and damage the shaft.

Wax impregnated flax packing has been around for ever and still a standard when this type of system is used. There are other newer tech packing such as GFO that have become popular over the years as they offer better heat dissipation allowing for a tighter fit and less lubrication which reduces the drip but I'd still be careful. The best way to go of course is to retrofit with a dripless shaft seal system.

Re: Shaft Packing

Posted: June 6th, 2020, 9:14 am
by km1125
Viper wrote:Source of the post
....
Have pick with little hook hook on the end, remove the nut and pick out all the old packing inside. You will get some water coming in but it'll be manageable. I like wrapping a rag around the shaft at the tube.
...


If you cut up a old bike inner tube and make a strip of thin rubber about 2" wide by a couple feet long you can wrap this over the joint where the shaft goes through the threaded part and it will completely seal the joint while you work. Tie off the loose end to anything convenient to keep tension on the rubber strip. This gives you all the time you want (or need) to pick out all that old packing out of the nut and get the new packing in place. On my boat, I can only back the nut off about two inches so there's not a lot of room to work with getting the pick in there.

Re: Shaft Packing

Posted: June 11th, 2020, 6:58 pm
by Coastie78
Thanks for the reply Viper and KM1125. The information that you provided is extremely helpful, and eases my mind about the task of repacking.

Re: Shaft Packing

Posted: July 4th, 2021, 11:22 pm
by Outlaw
There is more than a drip happening on my port v drive shaft. Is this normal or serious? Looking for help and have a video to share. Thank y’all

Re: Shaft Packing

Posted: July 5th, 2021, 12:55 pm
by km1125
Outlaw wrote:Source of the post There is more than a drip happening on my port v drive shaft. Is this normal or serious? Looking for help and have a video to share. Thank y’all

Have you tried to do any adjustments? Likely all you need is to loosen the locknut and tighten down the main nut just a little, then tighten back up the locknut. Don't get it TOO tight... it should always drip just a little.

Re: Shaft Packing

Posted: July 5th, 2021, 6:32 pm
by Viper
Welcome aboard.

I agree with km. Be prepared though that given its age and limited accessibility, this may be original packing and that you may not be able to tighten any further or enough to make a difference. If that's the case, you may have to add a new strand of packing or better yet, remove all the old stuff and replace it. If you get away with tightening it a bit and it slows the leak, you must check it again after taking her out for a spin and readjust if needed.