Saturday, November 28, 2009

A Rough Day In the Garage

Black Friday took on a completely different meaning for me yesterday. While most of this great capitalist nation was out shopping for bargains, I was in the garage experiencing a completely different sort of stress. There were a few other things my day had in common with all the shoppers; it was expensive, and by the end of the day I was frankly too tired to write about it.

Earlier in the week I got the bushing back I'd ordered from the machine shop. You may recall that I need to mount a pulley to the tail shaft of the 11" WaRP motor so that I can run my AC compressor off of it. The bushing is beautifully made, take a look:

It's milled from a solid piece of aluminum, the cylinder is keyed so that it won't spin on the motor shaft, and he even milled a little ridge on the front side that perfectly holds the pulley in place. Very nice work.

So I fit it onto the tail shaft of the motor, and immediately realized I had two problems. In order to get the groves on the pulley to line up with those on the AC compressor, I would need to mount the pulley so far forward that I won't be able to use the motor RPM sensor that I have. I hemmed, hahed and scratched my head for a while, but there is no getting around it. Fortunately, there is a new type of sensor available that should work, but that's another $100 toward the cause. The only thing I've found I hate more than having to build something twice, is having to buy something twice. Very painful.

Turns out that may all be moot, at least for now. I was very careful to build the bracket for the AC compressor so that the pulley was flush with the face of the motor. If it didn't line up right, the belt would come off or simply disintegrate with wear in a short time. As I looked further I realized that while I'd lined it up perfectly on one axis, there was a tilt to the motor that I hadn't matched with the compressor.

Sadly I had to admit that there was no way it would work in it's present state. In reality the only way to make it work was to rebuild the brackets completely. Of course the problem is that getting the alignment right on one axis was hard enough. Getting it right on two will be crazy hard and frustrating. I realized the best, and correct solution is to build the bracket so that it mounts to the face of the motor rather than the chassis. Obviously that will be another custom made machined part. But there's no getting around it, it's the right way to go. Ultimately I decided to shelve that work for now. I want to get the car on the road and the weather is beautiful right now, so the compressor and all it's supporting parts came out. Perhaps in April or so, it can rejoin the rest of the car.

Moving on, I decided to figure out and install the off delay timed relay for the power steering pump. I labored over the electrical diagram for some time trying to coax out the mysteries that it held. After a few dark incantations I was pretty sure that I had it correct, so I hooked it up and tried it. Well, it didn't do quite what I wanted. It came on with power constantly fed through one contact, but never moving to the timed contact. I re-evaluated and decided I'd seen my mistake and tried again. This time it worked! Once.

Apparently, I wasn't supposed to send 12 volts to a particular pin. It managed to trigger the coil once and likely fried it in the process. So, a replacement is on the way to the tune of $27. Not not too much, but frustrating none the less.

From what I learned yesterday, I'll be able to wire everything up so that I can just drop the new relay in place when it arrives. I'm hoping that today will be much more productive and less costly.

No comments: