stuffing box

[wjs]

I have a 1981 9.2A. with a yanmar 2gm. Last summer I was told that I needed to repack the stuffing box as it had excessive drip and the "packing nut" was tighten as far as it could go. I want to repack now before spring launch.
West Marine sells the "flax shaft packing" but is comes in various diameters from 1/8 inch to 5/8 inch in 1/16 inch increments.
Anyone know what diameter size is required?

My marina wants to charge $535. to do this work and afterwards they want to check the shaft for alingment....if realignment is needed more work will be necessary and more $$$$. I am not convinced that checking shaft alignment is a necessary part of the repacking process.
Anyone have experience with this????

 

[woodster]

there is a good artical by Mainesail in Compass marine that may help you ....measure the inside dia. of the packing nut and the ouside dia. of the shaft ...subtract the two dimentions and divide by 2 and you will know what size packing you need ......wate a min i will go measure mine now......it5 measure 1" shaft od / 1 1/2" nut id so that figuers out to 1/2" dif divided by 2 =1/4" packing....buy at least 18" long just in case you miss cut the first attempt......hope this helps....

regards

woody

you can buy this packing from the SBO store

 

[wjs]

Woody
thank you for your quick response.

 

[Bob McKee]

I repacked mine several years ago, it took two layers of 1/4" packing, I cut the ends at about a 45 degree angle and offset the cut ends 180 degrees. If the shaft isn't out of alignment before you start it shouldn't need to be realigned after. My opinion.

 

[wjs]

thanks Bob.
The packing nut looks larger than any of the open-end wrenches I have....did you happen to remenber what size wrench you used?
thanks again for your help.
wjs

 

[Bergovoy]

i was told a ptfe packing material can be tightened more and will leak less.. or maybe not at all...

not sure if that is truly reccomended or not...

 

[BobM]

wjs - be sure that you "burp" your packing gland if you repack on dry land and launch. I had a ringing sound that I later attributed to failure to do this. I had overtightened the packing and what I thought was water dripping out was actually melted WAX! I ended up backing the nut off entirely while in the water accidentally (long story) and the amount of incoming water is nothing to fear. You could even repack while in the water as others have done. The biggest problem is limited access (I pulled the prop, shaft, coupling, etc... on my 9.2A) and the small amount of room to move the nut back on the drive shaft.

Note that 1/4 may be a bit big. I had mine packed by a professional marine machine shop and if I recall correctly he used 3/16. Not a big difference though.