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Hi I'm in the middle of a bit of a rebuild/deep clean myself on an old Spaz Vivaldi S1V1 and just curious on something. When I tore down the steam boiler parts I noticed really badly applied teflon tape which was basically doing nothing. I noticed (by searching) that you used molykote in your rebuild. I actually work on underwater robotics and we use molykote all the time on electrical subsea connectors and such, but I've not seen it used in a case like this and don't know how to apply it. Did you coat the threads on everything before tightening down? Where all did you use it and how? Thanks!

I'm not a plumber by trade but know a bit about plumbing. On the trade forums I've read there's a couple of ways of protecting threads. A common way is to first wrap the male threads in teflon tape and then smear them with a thread paste like Megaloc. A thread paste doesn't lock the threads together like Loctite it dries to a putty like seal. The teflon and paste do a good job to protect the threads and seal them. Molykote Dow111 as a dielectric grease would do the same as a paste without drying. I use thin teflon and/or molykote on fine compression threads to help seal and protect them from corrosion. When wrapping threads with teflon be sure to wrap clockwise if you've got righty tighty lefty loosey threads.

Coarse pipe threads I definitely wrap all the way and paste or grease them. They're cut to crush together as you tighten them. Go as far with a wrench as the thread will comfortably allow and watch the connection after you turn on the water and re establish pressure. If it leaks, give it a tighten up to 1/4 turn at a time until it stops leaking.

Boiler and boiler element bolts are commonly wrenched on really tight. It's hard to say what's best for those. Maybe best is an impact wrench or torque lever and nothing but a thin coat of grease to protect from corrosion. I put copper grease on my car wheel lug bolts to keep them from seizing but I've read where you shouldn't because lubing the threads up would allow you turn them beyond a reasonable torque and stretch them out. Stretching out a bolt could affect its ability to keep from unscrewing under pressure

Compression connections are a bit different. They use washers or flares to make a water tight seal which are more important than the threads. Wrap those threads to protect from corrosion but if there's a washer lube that up. If there's a flare don't over tighten. Start with hand tighten and gently torque with a wrench only if it leaks until it stops leaking.

To be honest Molykote specs don't specifically say it's a dielectric grease but it works as one from what I know. I use Molykote on wiring tab connectors as well to protect from corrosion. But I'm not a trained plumber or electrician.

Molykote was designed for the food industry to lube up seals under pressure, high flow and high heat, AFAIK. It's the only grease I need on my Cremina 67 cylinder and piston seals to keep the lever moving smooth and effortlessly for a good long time. Dow designed a robust long lasting food safe grease with 111.