How to trace a parasitic draw

Use a multimeter (not a VOM). Put the multimeter in ammeter mode (<10A). Make sure to switch the common to the correct socket. Make sure the key switch is off and the key removed. Take off the negative terminal of the battery. Put your foot on the brake pedal to drain any remaining current in the circuits. Hook the red probe to the disconnected negative terminal connector and the black probe to the battery. Look to see if there is a current draw, any more than a milliamp or two. If there is not, revise your hypothesis and suspect the battery. If there is, pull the fuses and replace them one by one until you find the fuse that makes the number on the multimeter readout drop significantly when you pull it, then troubleshoot that circuit. Trace it backwards from whatever utility it runs, disconnecting connectors in sequence moving towards the battery, until you unhook the connector that makes the number on the multimeter drop. The faulty circuit is now isolated.

EVs vs Ice

r/sustainability question: EVs seem to be all the rage when thinking of ways to sustainably travel, aside from, of course, public transit, but how does the price stack up to traditional ICE vehicles? Are they worth the switch, or is it just going to drain the wallet?

How do electricity rates stack up to gas prices? What about maintenance costs?

Lots to consider, let me know your thoughts.

Intelligent Tinkering: The only way an ICE vehicle beats an EV for ease of use, cost effectiveness, and GHG emissions/mile is 1) if it's a plug-in hybrid used properly, so the first roughly forty miles are EV miles but there is no range limitation or worries about winter heating shrinking range in a cold climate, or 2) if the standard offer electricity supply in the region is particularly dirty with coal and no attempt is made to mitigate, or 3) it is used for heavy work where the energy density needs for efficient use are higher, so heavy towing, snow plowing, and so on, or 4) if it is an older ICE vehicle that has outlived multiple average vehicle lives. Embodied emissions in EV vehicles mean that they are not climate neutral even when run on solar, and the ratio of lifetime fuel consumption to embodied emissions for an ICE vehicle is about five to one, so it is not so hard for an older ICE vehicle that has exceeded multiple average lifetimes to catch up with an EV in total emissions/mile (including embodied emissions). We should note that the "error bars" on applicable studies of embodied energy in EV manufacture remain high. This is because of doubt in the energy costs of materials sourcing. 

https://www.iea.org/data-and-statistics/charts/comparative-life-cycle-greenhouse-gas-emissions-of-a-mid-size-bev-and-ice-vehicle

Sludged up or bad switch?

Kubota tractor owner: What is the simplest way to clean out the crank case? Manual says rinse with kerosene and somehow wipe it down. I'd like to pull the pan and rinse from the top. Also r&r the oil pump. Pull the engine or pull the front axle? Did an oil change and new oil is filthy after a short run and oil pressure light is on. Should also mention B6000 4x4.

Intelligent Tinkering: If the oil pressure light wasn't on before the oil change and is on now, you probably should make sure it is actually working. It should go off at higher rpm. If it doesn't, I'd suspect the pressure switch. You can take it off and check with a VOM set to the continuity setting, using air pressure (turn the compressor output down to less than 30PSI), or check it by replacing it. If that doesn't help, there are two causes of low oil pressure: bad pump or bad bearings. Bearing wear is far more common than pump wear because the design of the pump is robust. When bearings wear, their ability to hold pressure drops. But typically the light will still go out at higher rpm. It's unlikely the sludge has accumulated in the oil passages. I've stripped down a lot of engines and any sludge is usually just in the sump.