Stuffing Box Grease

[billwa]

Hi all,
I have a "new" boat that I need to repack the propellor shaft stuffing box on.

The internet has advice on repacking, but none of the sites seem to dealing with greasing the stuffing box.

My stuffing box has a grease nipple fitted on the water side of the stuffing.

How much grease, how often should I be greasing the stuffing box?

Also, adjusting the stuffing box immediately after greasing seems to give a poor adjustment.

What do other do, adjust then grease or grease then adjust?

Any advice?

[Laidback]

Originally Posted by billwa

Hi all,
I have a "new" boat that I need to repack the propellor shaft stuffing box on.

The internet has advice on repacking, but none of the sites seem to dealing with greasing the stuffing box.

My stuffing box has a grease nipple fitted on the water side of the stuffing.

How much grease, how often should I be greasing the stuffing box?

Also, adjusting the stuffing box immediately after greasing seems to give a poor adjustment.

What do other do, adjust then grease or grease then adjust?

Any advice?

If not more important than when to grease, is to know what type of grease should be used and what type should not. Remember stainless steel in salt water.

[daddle]

Grease? I thought ya just used the teflon impregnated flax. But I'm a sailor, what would I know? Gord?

[Pete7]

Originally Posted by billwa

Hi all, I have a "new" boat that I need to repack the propellor shaft stuffing box on. The internet has advice on repacking, but none of the sites seem to dealing with greasing the stuffing box.

My stuffing box has a grease nipple fitted on the water side of the stuffing. How much grease, how often should I be greasing the stuffing box?

Also, adjusting the stuffing box immediately after greasing seems to give a poor adjustment. What do other do, adjust then grease or grease then adjust? Any advice?

You are mixing two thing up here. Repack the stuffing box and adjust etc in accordance with the instructions on the net. Then in daily use we put a small amount of grease into the stuffing box before starting the engine. Actually we had a grease pump permanently connected and just gave a turn on the plunger each day.

However it the whole thing was a disaster. Requires a regular drip of water to keep cool when the shaft is turning so wet bilges and finally sprayed grease all over the place, Yuk

Replaced the whole thing with a Volvo seal. No more leaks, once a year grease job, clean and simple. Now have dry dusty bilges Does require a squeeze if you dry out to remove any air trapped inside, but thats it. Cost about $75 and a couple of hours work, good for at least 5 years and many have done more.

Pete

[Blue Stocking]

It somewhat depends on the type of assembly your boat has. If yours is of the type that has in internal, adjustable packing gland, fitted into a shaft log tube, and then to a cutless bearing (or not), the nipple injects the grease between the packing and the ocean. The water pressure helps to seal against intrusion of water.
Many older boats, and even some newly built "traditional" boats still use this set-up with a remote McCoy-type screw cap grease reservior. BTW, thats where the saying "its the real McCoy" originated, but from use on steam engines.

[GordMay]

What make & model of stuffing gland?

[FSMike]

Originally Posted by Blue Stocking

--- a remote McCoy-type screw cap grease reservior. BTW, thats where the saying "its the real McCoy" originated, but from use on steam engines.

I thought the term "the real McCoy" came from a US prohibition era bootlegger named McCoy?

[GordMay]

There's numereous etymologies claimed for "the real McCoy".
See ➥ The Real McCoy

[Blue Stocking]

Gord,

If I may be allowed to thread drift a bit, at the NW corner of St. Georges harbour, Bermuda, is the remains of a 1 thousand ton marine railway. Taken out of service about 3 years back, with hauling records back to 1870, the original steam engine which powered it is still there, and yep, you guessed it, is fitted with McCoy screw type grease cups.

[GordMay]

Originally Posted by Blue Stocking

... the original steam engine which powered it is still there, and yep, you guessed it, is fitted with McCoy screw type grease cups.

Elijah McCoy, the Canadian inventor, made a successful machine for lubricating engines which spawned many copies, all inferior to the original. He patented the design in 1872 (Patent #129,843).

This is one of many plausible suggested origins for the phrase.

[svpresent]

@Pete7,

Can you tell me what length I need for installing a Volvo seal counting from the end of the propshaft-tube ?
I couldn't fit in a PPS-seal on my 40 mm shaft but maybe a Volvo would fit.
TIA!
Cheers, Len.

[Pete7]

Len, our shaft is 1" so the volvo seal is about 3" of which 1" sits on the stern tube. Suggest you pop down to the nearest Volvo dealer with your shaft diameter, stern tube diameter and length etc.

Photo is rubbish but gives you the idea. Don't forget though you will now need a vacumn cleaner to hoover out the bilges before polishing them :-)


Pete

[MitchM]

remember you cannot change the PSS seals in-water, the boat must be hauled. most long distance cruisers find taht a disadvantage of the PSS seals.
i have the mc coy grease gun on my boat a nauticat as original equipment. feed lithium white marine grease in once each month using the handle then check that the water lubrication is 1 to 2 drips per minute as this water drip is necessary to lube the prop shaft. if you run out of grease in the tube, when you turn the mccoy shaft to add more grease, the handle will be full in.

[svpresent]

Thanks a lot Pete7, also for the picture
I'll defenitely look for a Volvo dealer and get me a pair (yes, we have a twin engine... double maintenance!)

[billwa]

Originally Posted by GordMay

What make & model of stuffing gland?

Dont know, so heres a picture....

Repacked it this weekend. Seems to work OK. I bought some picks and they were brilliant.

Changed it in the water, had maybe 1/4 a cup of water come in while I worked on the box for 30 mins.

This is the first repack I have ever done... first since I bought the boat.

Interestingly, the previous owner had double looped the middle ring, which was a total bitch to get out of the box. So when I put new ones in I didnt double loop. the middle ring.

Thanks to all for the advice. Will move on to project 2 this week.