I replaced my original bronze shaft with a SS as well as the Stuffing Box and Cutlass this Spring. I motored to my slip this morning and kept checking the Shaft temperature. It seemed cool to the touch and no different from the bronze I was used to. I stopped checking after a while as I had to clear a few bridges. When I arrived in my slip after 90 minutes of motoring I noticed the shaft was much warmer than in the past and the new Transmission Coupler was actually hot as was the Transmission Housing. Does this sound normal or is the Stuffing too tight? My initial thought is the new Stainless Steel Shaft might be a better conductor of heat than the old bronze. Also, I might not have even thought to touch the Transmission Coupler in the past or even the Transmission Housing. For years I only touched the Shaft itself whenever I changed packing or launched. Nothing was that hot that I got burned, but much warmer than in the past.
Shaft Temperature
- Thread starter chief14326
- Start date
- Status
The trick is to check the stuffing box itself. Most likely too tight if you're getting heat that far away.
In Addition .............................
.................... to what Stu has stated, the tranny runs bloody hot as it produces its own heat from friction as well as conducting block heat. The Kanzaki tranny on a Yanmar has cooling fins to help dissipate the heat.
It would be interesting to use an infrared gun to see if the temperature rises or falls going from the shaft coupling to the gland. This would tell for sure who is the source of heat.
.................... to what Stu has stated, the tranny runs bloody hot as it produces its own heat from friction as well as conducting block heat. The Kanzaki tranny on a Yanmar has cooling fins to help dissipate the heat.
It would be interesting to use an infrared gun to see if the temperature rises or falls going from the shaft coupling to the gland. This would tell for sure who is the source of heat.
Re: In Addition .............................
most important, you didn't say if you were dripping water. i personally prefer a litle more water than less since nobody has ever told me cogently why not. the purpose of the whole deal is to lubricate the shaft with raw water.
most important, you didn't say if you were dripping water. i personally prefer a litle more water than less since nobody has ever told me cogently why not. the purpose of the whole deal is to lubricate the shaft with raw water.
Re: In Addition .............................
I am using Gore GFO Packing which is dripless. I am dripping a little, but that is to be expected as I just replaced. I would expect it to stop at some point. To everyone's point I never touched the Hurth Transmission before, therefore I am not sure how hot it ever got. I now cannot recall if the Stuffing Box was hot or just warm. I do know the new SS Shaft was warmer than the previous bronze. Hopefully, I will get at this weekend and as I have to motor out into the Atlantic I will have a chance to check everything again. My original question seemed logical at first; would Stainless Steel conduct heat better than bronze?
I am using Gore GFO Packing which is dripless. I am dripping a little, but that is to be expected as I just replaced. I would expect it to stop at some point. To everyone's point I never touched the Hurth Transmission before, therefore I am not sure how hot it ever got. I now cannot recall if the Stuffing Box was hot or just warm. I do know the new SS Shaft was warmer than the previous bronze. Hopefully, I will get at this weekend and as I have to motor out into the Atlantic I will have a chance to check everything again. My original question seemed logical at first; would Stainless Steel conduct heat better than bronze?
call hurth. like almost manufacturers - mainly except raymarine - they will answer your questions professionally; they did mine.
Conductivity of Brass vs. SS ...................
As far as the dripping of your gland, especially with GFO packing, there is no need for the packing to drip, ever. Just monitor the temp. every time you check for unwanted leakage.
From the literature I have read, yes, red brass is definitely a better conductor than SS, somewhere in the neighbourhood of 5-6 times as good. Chromium in the SS is a poor conductor while the copper in the brass is a good conductor.
As far as the dripping of your gland, especially with GFO packing, there is no need for the packing to drip, ever. Just monitor the temp. every time you check for unwanted leakage.
- Status