I run about 25 amps at 3.5 volts out of it into a four turn heating coil (about 12" of #12 gauge nichrome wire) wrapped tightly around the lower half of the injector body and insulated/held in place with stove cement. I salvaged the nichrome wire from a ceramic high wattage industrial motor starting resistor.Â
I like the idea of heating the injector body itself rather than the fuel line. Nichrome wire is easy to salvage from an old hot water tank heating element.
How did you insulate between the injector body and the nichrome wire ?
Where does one get 'stove cement' ? Is it just refractory like you get for wood stove that you mix with water to a heavy paste ?
How did you do the transition between nichrome and your copper power cable ?
Jens
The beauty of working with 3 or 4 volts is you don't get a shock hazard or much of a spark and little insulation is required. The stove cement comes in a prepared paste from the hardware store. It is the Sodium Borosilicate stuff used to install firebrick, etc. You could also use muffler cement. To insulate the nichrome I had a bunch of tiny ceramic beads strung the length of the wire but most got broken navigating the tight clearance between the injector body and the two mounting studs. Form/prepare the wire on the injector removed from the engine. You could just use the cement without the beads. I formed eyelet loops at the ends of the nichrome and bolted the copper #10 flex wires with small brass machine screws, nuts and flatwashers. You can forget solder here. The upper end of the heating wire does a single loop around the input stem which sticks out the side of the injector body at 90 degrees before it terminates. This helps secure the element from rotating or moving and adds a little heat where you also need it. The heater is wound onto the injector between the input port and where it meets the head, NOT up away from the engine near the back of the injector at the overflow exit port.
I initially used about 8 parallel strands of finer nichrome wire from a radiant heater snaked through the ceramic beads. It was much more flexible and I did not break the beads but some fuel drops got into the heater and quickly eroded the wire leading to open circuits and a heater failure in rather short order (first day). The #12 single strand has been going strong for many hours with no signs of fatigue.
As a bonus, you will find that this heater helps prep the engine for cold weather starts on regular diesel, even though some experts will tell you that this is nearly impossible. Of course you'd need to arrange a storage battery just for this purpose if you are setting it up to start without mains available. Once running the 120 volt generator AC powers the heater transformer. If you already have a 12 volt storage battery for cranking you could wire a DIY series resistor made from the same nichrome to limit the wattage to this injector heater, but the battery better be a big one since you want to run the heater for about 5 minutes before it will do much good as a cold start aid. That series R might as well be installed inside the metal intake manifold so it gets hot and gives the engine a shot of hot air rather than wasting this energy entirely.