SailNet Community banner
  • SailNet is a forum community dedicated to Sailing enthusiasts. Come join the discussion about sailing, modifications, classifieds, troubleshooting, repairs, reviews, maintenance, and more!

Temperature Sending Unit

2K views 9 replies 7 participants last post by  dorymate1 
#1 ·
I'm going to replace the water temperature guage and sending on my Atomic Four. What is the best product to presoak the sending unit for a clean removal and what is the best product to treat the threads when installing the new sending unit?
I find that PB Blaster is not particularly effective for stainless steel screws in aluminum, but have not used it on brass to iron fittings.
I appreciate any advice you might have.
Thanks
 
#2 ·
PB is pretty good

Raw SS and aluminum is one of natures better locktites and right there with red :)

I really have not had a real bad time with senders as they are brass and only have a few threads in the block

Just be sure to go at it with a 6 point tool as once you round it off you kind of screwed
 
#3 · (Edited)
Here's an easier, cheaper solution I used for several years after the temperature sensor packed up: buy an inexpensive, digital hot tub thermometer -- they come with the sensor at the end of a 5 ft (or so) insulated wire. Attach a small fishing weight to the sensor end of the wire and drop it down a cockpit drain. You don't need water temp all the time -- normally, only when you're thinking of going swimming or wanting to detect entry or exit from an ocean current (like the Gulf Stream). The hot tub thermometer works well for this purpose and when not needed it fits easily in a drawer/locker (the read out unit is really small 2 x 2x 1 inch.)

I have since replaced the speed paddle assembly and now have a proper temp sensor installed. The hot tub thermometer now serves as a battery temperature read out when I'm putting a big charge in the batteries on a hot day. I wedge the sensor between the cases of two batteries and set the display unit where I can see it easily.
 
#4 ·
Here's an easier, cheaper solution I used for several years after the temperature sensor packed up: buy an inexpensive, digital hot tub thermometer --
... ummm.... BR, he's trying to change his A4's coolant temperature setup.. I think the sea temp might cause some confusion! ;) :p :D

Neat idea, though... :)
 
  • Like
Reactions: Silvio
#5 ·
You do not want to put anything on the threads of the sender as it needs electrical contact with the motor block to ground the unit. I've replaced and removed mine several times and it really shouldn't be too tough. I've always found a crescent wrench to work fine, and they are not the best for anything really stuck. You may be surprised with the ease of removal. And PB is great, but likely not that helpful in this situation.
 
#10 ·
Not being a pool guy don't realy know what a hot tub thermometer is. But would most likely hose. Clamp. It wire tie itor safety wire it before silicone. Not heat resistant enough unless RTV that works when mechanically squeezed. Engine parts are also to greasy for silicone. Leave the silicone in the drawer for this one.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top