hot prop shaft

[tamarix]

How hot should a prop shaft get?.........or should it get hot at all?

 

[sarabande]

any part in particular ?

Thrust bearing
Gearbox
Stuffing gland
Doughnut fitting

....


and how hot ?

too hot to touch for more than a second
etc.


If you know someone with an infrared thermometer you could use it to give a quantitative reading.

 

[tamarix]

Sorry stuffing gland end and you wouldn't want to touch it for more than a couple of seconds

 

[sarabande]

ok, so how is gland lubricated ? What type (make / model) ? Grease only, water. What maintenance / burping have you done recently ?

 

[Piers]

I assuming you have a prop shaft which goes from the gearbox through the stuffing box and to the prop, the shaft being held in place with a A or P bracket close to the prop.

One cause of heat in the stuffing box is if the face plate has been tightened too much, placing too much pressure on the stuffing making it too tight around the shaft preventing proper cooling from sea water and overheating. When not turning, you should have a drip every second leaking through.

A normal heat would be a max of around 25C max. Any more than this might start to cook the grease in the stuffing making it brittle and friable thereby losing its watertightness. Nasty.

Another cause could be an out of alignment shaft.

Needs investigation.

 

[DAKA]

I assuming you have a prop shaft which goes from the gearbox through the stuffing box and to the prop, the shaft being held in place with a A or P bracket close to the prop.

One cause of heat in the stuffing box is if the face plate has been tightened too much, placing too much pressure on the stuffing making it too tight around the shaft preventing proper cooling from sea water and overheating. When not turning, you should have a drip every second leaking through.

A normal heat would be a max of around 25C max. Any more than this might start to cook the grease in the stuffing making it brittle and friable thereby losing its watertightness. Nasty.

Another cause could be an out of alignment shaft.

Needs investigation.

Good response , gets my vote

 

[sunquest]

More importantly, is the sea water reaching the gland?

 

[tamarix]

Thanks for the replys . Piers that is very interesting i've never had any drips when the shaft isnt turning. As you say I will investigate further.

 

[vyv_cox]

There's a lot of information about the various types on my website under 'stern glands' along with links to other sites that go into more detail than I do on how to set them up. The site is sail oriented but not much difference when it comes to stern gear.