Sheepboy--

If you have disconnected the glow plugs the voltage will certainly be in the range of 11 or 12 volts as no current will be flowing to drop the voltage.

Transformers will work only in AC circuits so not good for this problem.

This engine (even with it's quirky glow system) is usually very reliable. If you can get this problem sorted out you will probably be happy with the engine.

Paul