Shaft seals and shaft alignment

[Seastoke]

Can these be done in the water and how to do ,cheers roy

 

[superheat6k]

Can these be done in the water and how to do ,cheers roy

What is the engine shaft arrangement ?

What shaft seals do you have ?

 

[MapisM]

Does that matter? Unless I misunderstood the OP question, the answer is clearly NO regardless, in my books...

 

[rotrax]

It is possible to do the alignment in the water, and it is possible to change the stuffing material in the water. I doubt I would attempt to change a complete stuffing box in the water though. Others might have a go, but not me!

 

[Bandit]

Its a bit difficult not knowing the type of sternseal, but out of the water is best for stern seal work or replacement.

You can align the shaft in the water however it is often better to draw the shaft do stern seals, cutless bearings, check the shaft for truth, check taper and key, shaft alignment and then line up the engine then check it again in the water.

If you are replacing a stern seal and want a good dry seal with no water in the engine room, look at Tides Marine seals.

 

[volvopaul]

Can these be done in the water and how to do ,cheers roy

From memory of the engine survey you have standard packing type glands .
The book says always set engine alignment with the boat is the water as there is no hull flex and the boats hull is equally supported .
I question why you think you need to do this ?

I will possibly be competing next February on the Cambrian rally which starts at Llandudno, if I do I’ll let you and Bruce know.

 

[Kawasaki]

Can these be done in the water and how to do ,cheers roy

If you have ‘trad’ type packing yes
And alignment is possible afloat
When u at the boat next?

 

[MapisM]

The book says always set engine alignment with the boat is the water as there is no hull flex and the boats hull is equally supported

Aha, now I understand the confusion behind my previous reply.
I agree that ENGINE (or v-drive, depending on layout) alignment can be done with the boat in the water, but by SHAFT alignment I assumed that the OP meant the check which afaik can only be done bringing the shaft to a specialized workshop, using a large enough lathe, forming press, or whatever else it takes...

 

[MapisM]

If you are replacing a stern seal and want a good dry seal with no water in the engine room, look at Tides Marine seals.

Or even better, look at Tides Marine first, and then compare their stuff with Fluiten seals.
It'll be sufficient to look at their pics to understand why the latter is in another league.

 

[Seastoke]

Well my starboard seal looks like it has been spraying water around should I tighten the two bolts then take it out and check ,how much should I tighten and I assumed that if it was spraying they must be out of line ,ps can you tell this when you are going forward and what speed and yes Paul would be good to catch up with a beer

 

[oldgit]

Well my starboard seal looks like it has been spraying water around should I tighten the two bolts then take it out and check ,how much should I tighten and I assumed that if it was spraying they must be out of line ,ps can you tell this when you are going forward and what speed and yes Paul would be good to catch up with a beer

if no other problem,then the outer locknuts should be slacked off and the inner nuts tightened a tad until the shaft only drips about once per second.Mine are tightened till no drips and then slacked off a flat or two.. inside the gland there will be several rings of square packing material which allow water to cool shaft but prevent water entering bilges. This website is excellent tutor on the mysterious world of stern gear. http://coxeng.co.uk/stern-gear/ It does help if previous owners have not simply jammed extra packing on top of the older stuff which then goes rock hard and is pig to get out.You can change the stern gland packing in the water even if the above is true. If you think shaft is seriously out of alignment you could check with dial gauge inside the boat for clues

 

[Bandit]

The beauty of a good seal that is watertight is no more water and grease in or sprayed around the engine room.

I would not have a packed seal if you paid me.

Its worthwhile engineering out the packed seal and fitting Tides, they are good, good parts supply and reliable.

 

[superheat6k]

Does that matter? Unless I misunderstood the OP question, the answer is clearly NO regardless, in my books...

You need to buy some more books !

 

[Danfarry]

Roy, just sent you a PM. Had my port shaft aligned and a new seal. The boat did need to be lifted. Had the cutlass done as well.

 

[MapisM]

You need to buy some more books !

LOL, books about nautical English, possibly - see my post #8.

Apropos, if not "shaft alignment", how would you call the control that you can only make after removing the shaft completely, to check if it's perfectly straight (and possibly straighten it, if necessary)?

 

[MapisM]

Its worthwhile engineering out the packed seal and fitting Tides, they are good, good parts supply and reliable.

I'm not saying they aren't, but as I previously mentioned, Fluiten seals are even better.
Just give them a look, if you never did.
It really is sufficient to look at the pics, to understand why they are superior to anything else (up to 300mm shafts, btw!).

 

[Grubble]

LOL, books about nautical English, possibly - see my post #8.

Apropos, if not "shaft alignment", how would you call the control that you can only make after removing the shaft completely, to check if it's perfectly straight (and possibly straighten it, if necessary)?

I would call that checking the shaft is "straight" as opposed to "bent". If it turns out the shaft is bent, it would then need to be straightened. More technical words used might include "run-out" and "true".

 

[MapisM]

Aha, got it, thanks. Down here, that's exactly what we would call checking the shaft alignment.
The alignment between g/box (or v-drive), through hull and P bracket is in fact described in a way that could be literally translated as "construction (or installation) alignment".
Actually, after your explanation, I guess that this doesn't mean anything in EN, but you see what I mean...

 

[JerryC]

Re post #17 ... 'if the shaft was bent' ... crikey, you would surely feel the vibration if that was the case and it would be a no brainer to lift out?

I can recommend Tides Marine shaft seals, no packing to check and tighten, no constant slight drips into the hull, so hull dusty dry, that's the way I like it . Water lubricated by a trickle from both engines, from both to each seal. They also have a second replacement seal pre-mounted 2 inchs above the first one, so if the first one starts to go, the replacement can be slid down easily to replace it, with boat in the water. What's not to like?

 

[MapisM]

Re post #17 ... 'if the shaft was bent' ... crikey, you would surely feel the vibration if that was the case and it would be a no brainer to lift out?

It depends. Gravity force alone can be enough to bend the shafts in a boat not used for a long time, but not to the point of creating evident vibrations.
Still, that can be instrumentally measurable, and such deviations can normally be adjusted.
Badly bent shafts due for instance to grounding not only introduce awful vibrations, but they are mostly beyond repair.

Water lubricated by a trickle from both engines
...
What's not to like?

Precisely THAT is one thing not to like - together with the flexible hose, which is solid, but not as much as bronze or s/steel.