Stern Tube Temperature

[IrlSail]

Hi,

I re-packed the sterntube over the winter. I did not tighten the collar; wanting to wait until the boat was in the water so I could adjust according to the drip (aprox 3 every min i'm told is normal when running). However I have no drip even when i completly slacken the collar!! The packing housing gets quite hot, is this normal? I never felt its temperature before putting in the new packing so don't know was it hot before. I had to run the engine for 5 hours yesterday due to lack of wind on while on passage up the Irish coast - still no drip, the housing got hot but no hotter than it was after 30 min running. I am using a waterproof grease, would this be preventing the water reaching the packing? The engine is a Volvo MD5A.

Any insight anybody may have would be appreciated.

 

[eyehavit]

I re-packed the sterntube over the winter. ................However I have no drip even when i completly slacken the collar!! <span style="color:blue">When underway or at rest? </span> The packing housing gets quite hot, is this normal? <span style="color:blue"> No. The packing gland should not run excessively hot because there is risk the shaft could overheat and bend.</span> I never felt its temperature before putting in the new packing so don't know was it hot before. I had to run the engine for 5 hours yesterday due to lack of wind on while on passage up the Irish coast - still no drip, the housing got hot but no hotter than it was after 30 min running. <span style="color:blue"> What was the (estimated) temperature reached? </span> I am using a waterproof grease, would this be preventing the water reaching the packing? <span style="color:blue"> Not normally but if the stern tube was heavilly filled with grease it might, although a 5 hour run s h o u ld have cleared the surplus. </span> The engine is a Volvo MD5A.

 

[IrlSail]

No drip when underway.

I'm not the best at estimating temperature but i could only put my hand on it for 2 or 3 seconds, similar temp to head of the engine.

 

[eyehavit]

That could put the temperature around 60 deg. C.
Is there a bearing immediately behind the packing?

 

[IrlSail]

I'm not sure, directly behind the packing housing is a short piece of black rubber hose held in place with jubilee clips, no possible to remove without taking the shaft out!

 

[Piddy]

Hi

I had this last year - new packing, no water and heat.

I ran it for a few hours, checking it anxiously and after a couple of weekends normal use, it cooled down and has been fine since. There's still very little water though.

Hope this helps!

 

[eyehavit]

That does not make sense at least to me. Could you post a pic(s) on the forum showing the existing arrangement? If not just send the pic to my email.

 

[IrlSail]

Yes will do, I don't have one at present but will take one tomorrow evening when i go down to the boat.

 

[Danny]

You should certainly get a drip or two of water per minute when the engine's running. If it's too hot to keep your hand on then it's way too hot. Did you use the right size packing? Waterproof grease is OK - it's supposed to make the packing waterproof but allow a film of water to lubricate between the packing and the shaft - hence the drip.

 

[Spyro]

[ QUOTE ]
Hi

I had this last year - new packing, no water and heat.

I ran it for a few hours, checking it anxiously and after a couple of weekends normal use, it cooled down and has been fine since. There's still very little water though.

Hope this helps!

[/ QUOTE ]

Also had the same last year after repacking. It got a bit hot some grease softened and ran out now it runs very cool with hardly any drips.
Also your arrangement with a stern gland gaitor held onto a stern tube with jubilee clips sound normal to me.

INFO HERE and HERE

 

[Spyro]

Should have checked the link, I'm beyond my edit time
so here it is again INFO HERE

 

[Caer Urfa]

Also had the same last year after repacking. It got a bit hot some grease softened and ran out now it runs very cool with hardly any drips.
Also your arrangement with a stern gland gaitor held onto a stern tube with jubilee clips sound normal to me.

Agree, have same on a Colvic Watson, stern tube also ran hot after packing and filling with stern gland grease, now one year later I can touch the gland but would not grab and hold it, no drips works fine!

 

[joeh]

hi
i have a MD6A with a 1 inch prop shaft
what may i ask was the diameter of the flax packing u used ?