Exercising The Crown

Perhaps I've been guilty of diesel abuse. I couldn't remember the last time I started my bus. I know it wasn't last year, because I was dismayed that the weather had gotten cold so quickly and I hadn't done it (I like to run the bus in hot weather, it means it starts willingly without having to apply ether starting fluid). I can't remember if I started it in 2010 or not.

We've been having a bit of late summer heat, highs in the 85° range, and I decided that I couldn't put it off any longer, else I risk the weather taking a plunge and it being another year before I got around to it.

Yesterday, I gave the big 8D batteries a top-up charge, each with their own 10 ampere charger. I keep the batteries disconnected, and they have their own solar panel, which I connect alternately to pump a few electrons into them on a semi-daily basis. One battery was "playing possum", it was exhibiting low terminal voltage, even after hours on the charger. As soon as the charger was unplugged, it would dive to 8-something volts, not good. The other battery was resting comfortably at 12.25 volts, not red-hot but not acting dead, either. During operation, the two batteries are connected in parallel, so the total voltage is nominally 12 volts.

The first thing I do when starting the bus after sitting, is to pull the compression release lever on the back of the cylinder head, and then run the starter until the oil pressure comes up on the gauge on the dashboard. I decided that the low battery was probably toasted, so I connected only the "good" battery for this first spin. It actually only takes one good battery to start the bus, so I thought I'd just use the one. It did manage to turn the engine over, but not very fast, and not for long, even without the full load of the engine's compression.

Since I had nothing to lose, I then put the "weak" battery in parallel with the one I had just tried I wasn't expecting that this would help, but it was easier than pulling both the batteries and then scratching around for something else to try. I also put my big battery charger on the two batteries, the one that I rebuilt from a scrapped gas station charger. It can pump out 100 amps at 12+ volts, just the thing to refill the batteries from cranking and assist in the current draw during. To my surprise, adding the "weak" battery made the starter spin the engine at normal speed, and the oil pressure came up right away. I then took the compression relase off and cranked again and the engine sprang right to life, as if it had been shut down just a few minutes prior. Outstanding.

I let the engine idle for a while, then revved it up, blowing out some quantity of blue smoke, the product of my cranking with the compression relase engaged. Worked the clutch and brake pedals, released the parking brake and put the transmission in first gear, releasing the clutch just a bit to rock the bus on its tires to make sure that none of the brake shoes were seized to the drums, and to clean off any rust on the clutch pressure plate.

Shut the engine down when it came up to temperature, then rolled under the bus to open the moisture drain valves on the three air brake pressure tanks. Only the rear reservoir had a small amount of water in it.

I left the big battery charger on the batteries for a few hours afterward, then disconneted it, and disconneted both batteries from the bus electrical system. The "weak" battery was now exhibiting a terminal voltage of 12.67 volts, fully charged. Sometimes these flooded lead acid cells need a little exercise to get them acting brawny again. I washed the battery tops with clear water, sponged off the excess and pivoted them back into the underbody of the bus. Done for another year.

I've been letting the ferns grow on the north side of the bus.

Why would anyone else want to read a blog post about me starting my engine? Good point. Now I have a record of the last time I did the deed, and I can look it up to make sure that is isn't two (or three) years back.