Stern gland stuffing

[wee_niall]

Just following on from my worn shaft thread and cutless bearing saga, i've been having a look at the inboard end of the stern gear and thought i'd have a look at the stuffing box and either repack it or replace with a lip seal.

Firstly, i can't see how this stern gland (is it a stuart?) could be modified to accept a maintenance free seal so i guess i'm stuck with it unless i change it which might be tricky since i'd imagine that current fittings won't be compatible with the stuart tube threads. Also, does this gland have a bearing within it? I had a feel and it doesn't seem like there is anything after the seal but i guess that doesn't mean there shouldn't be

The other question i've got is the actual seal - i was expecting to pull out rings of standard stuffing material but it seems to be a single piece thing....can this be replaced with another single piece or can it be swapped for rings (3?) of normal stuffing?

 

[NormanS]

Why would you want to change from the excellent simplicity of a conventional, and properly attached stuffing box? Just repack it with teflon packing, as many rings of the correct size that it will comfortably take. If you try pulling apart the stuff that came out, you may well find that it is rings all stuck together with grease.

 

[vyv_cox]

Why would you want to change from the excellent simplicity of a conventional, and properly attached stuffing box? Just repack it with teflon packing, as many rings of the correct size that it will comfortably take. If you try pulling apart the stuff that came out, you may well find that it is rings all stuck together with grease.

+1 on all counts. Just replace the packing following the usual instructions and all will be well.

 

[GHA]

Why would you want to change from the excellent simplicity of a conventional, and properly attached stuffing box? Just repack it with teflon packing, as many rings of the correct size that it will comfortably take. .

+ another 1
ASAP do Ptfe packing, great stuff.
http://www.asap-supplies.com/marine/ptfe-flax-gland-packing

 

[Tranona]

That inner bearing housing can be machined down to take a Volvo seal, but if the white metal bearing inside is OK would not disturb it, but do as suggested and just repack the stuffing box. When I did mine the white metal was gone, so I had it bored out to take a cutless which then makes a water cooled Volvo seal a better solution.

 

[wee_niall]

excellent stuff guys - i guess that makes sense as it's probably decades old that stuffing and has just formed into a single mass. I was thinking about the dripless seal as getting to the stern gland with the engine in place is pretty much impossible but i think even with a "maintenance free" one that's not a good idea so i'm going to put a wee access hatch from under the quarter berth into the engine compartment so that it can be inspected/adjusted.

 

[wee_niall]

That inner bearing housing can be machined down to take a Volvo seal, but if the white metal bearing inside is OK would not disturb it, but do as suggested and just repack the stuffing box. When I did mine the white metal was gone, so I had it bored out to take a cutless which then makes a water cooled Volvo seal a better solution.

I'll need to have another look but i couldn't see any evidence of a bearing after the seal area - it just appeared to widen out to the stern tube immediately aft of the seal. Speaking of the packing - what width of packing should i go for and how many rings are advisable?

 

[VicS]

I'll need to have another look but i couldn't see any evidence of a bearing after the seal area - it just appeared to widen out to the stern tube immediately aft of the seal. Speaking of the packing - what width of packing should i go for and how many rings are advisable?

Measure the shaft diameter and the id of the housing to determine the size of packing required. Fit as many rings as possible. There does not look as though there is room for many and there does not look as though there is going to be much scope for adjustment so it will probably be obvious how many will be required .

When you refit the engine be sure to line it up properly. The prop shaft, centred in the gland, and the gear box output shaft must be in in line with each other with no angle between them and no displacement vertically or laterally.
If necessary take some time to find out how to do this properly.

 

[RivalRedwing]

If you did want to go to a Volvo or similar you will find Lake Engineering in Poole to be very helpful - they did just that job for me, all I supplied was the compression fitting to give them the stud locations. A very reasonable price too as I recall. No affiliation etc