My Blog

Most of the things that I build are excessively nerdy computer things (probably not by comparison of some things people do to computers) or actually physical. I think this next thing might be a little different.

I just moved out to Nashville a couple months ago to start my new job, and the only bad thing about it so far (besides not being able to surf after work like I did almost every day in Charleston) is my bathroom. It’s an odd shape, and the switch for the fan is on the other side of the bathroom from the door, the light switch, and the shower! It’s conveniently placed by the toilet though, so go figure.

I wanted a switch to operate the fan too. I found a three-position double-pole double-throw center-off switch in my truck’s toolbox. With the switch up, the fan is on all the time, with it in the center it is off all the time, and with it down it is on when the lights turn on.

I have been trying to convert .MKV files to .AVI for a long time! Today I finally found a way to do it (for free, as per usual) in Linux. (I am currently using Ubuntu 10.04 Lucid Lynx.)

OK this is mostly a note for myself because I’ve come across this problem many times.

In Linux (Ubuntu) to rip music using Rhythmbox, a “GStreamer Pipeline” must be provided. I rip at 320 kb/s because I can, and the pipeline for that is

audio/x-raw-int,rate=44100,channels=2 ! lame name=enc vbr=0 bitrate=320 ! id3v2mux

It took me a long time to find that. Any way, more things will follow now that I’m no longer a student or having an awesome summer or moving. Hooray!

So my neighbor calls Monday night from the BB&T parking lot. Maggie (the Jeep) won’t start! My truck’s radiator is in the living room so I put a bunch of tools in Sue and we drove off to try and get the Jeep fixed. All the electrical equipment in the Jeep was working, but I decided to try and jump it off any way. That didn’t work. I had this same problem right after I bought my truck though, where the truck wouldn’t jump off because the battery terminals were bad. So I cleaned the battery terminals on the Jeep. That didn’t work. All that was happening was the Jeep was making a clicking sound from around the transmission whenever anyone tried to start the ignition.

4.0 I6 Jeep engine.

So I call my other Jeep friend for a tow (because my truck is out of comission, sadly), and while he’s there we decide that we should just hit the starter motor really hard with a blunt object. This got the Jeep cranked up well enough to drive home, but seeing as how my neighbor can’t just get under her Jeep and hit it with a hammer every time she wants to go somewhere, I decided to look into replacing the starter motor. (The reason this works, temporarily at least, is because when the starter motor goes bad it sticks and won’t turn at all unless it’s nudged a little by a hammer blow or something like this. This is only a temporary fix, eventually even hitting it really hard won’t get the engine turned over.)

I found a forum post about someone who was having the same issue. The solution is fairly straightforward: Remove two wires, then two bolts, don’t let the old motor land on your face, put the new one in, screw in the bolts, attach the wires. Oh yeah. DON’T DO ANY OF THIS WITH THE BATTERY HOOKED UP. Remove the negative terminal first. Otherwise, bad things will happen. Some of the bolts are in kind of an awkward position, and I had to use a cheater bar to get the topmost bolt started, but it was a fairly simple fix.

Forum Post!

Another important point is that the starter motor is not in oil in the engine, so when the motor comes out, oil should not spill from anywhere. This brings up something interesting that happened while I was doing the repair, though. When I removed the positive and negative wires from the starter motor, old engine oil had collected in the housing for the wires and leaked out all over everything. This is perhaps proof of the theory that the starter motors in these Cherokees go bad faster than normal due to their location directly under the oil filter. So, any time the Jeep goes in for an oil change, dirty oil spills all over the starter motor. Not exactly healthy. But the entire engine bay of this Jeep was covered in WAY too much grease which somehow got on my pants? Seriously. It went everywhere. So I’m not going to fret over a little stray engine oil.

Any way, here are the pictures:

The hole just above the oil filter (white) is where the new starter motor will go. This was right after I removed the old one. It is a view from above the engine bay.

This is the view from below the engine bay. The flywheel is visible in this picture.

Old and new starter motors. And some red duct tape. The new starter motor cost right around $100 from Advance Auto, but when they get the old one back they give out a $30 rebate. Not really sure why, but that brings the total to about $70 for the parts.

Also important to note is that the bolts for the starter motor are different lengths. The short one goes on the top, the long one on the bottom. It took A LOT of cranking on the socket wrench to get them back in. But all in all, not a huge deal.

New starter motor. Complete with my greasy fingerprints. Awesome! After that, I hopped in the Jeep and it cranked right up. Fixing things is handy. Can’t believe that Clemson Automotive wanted almost $400 to do this repair. Pretty ridiculous. Hooray saving $330!

I will be doing this project in parts because it’s fairly labor-intensive and should take a couple of days. Turns out my truck has a timing belt in it, and not a timing chain like the guy who sold it to me told me it had. Any way, the Nissan dealer wanted $759.95 to change the timing belt, but the parts (including a new water pump, new thermostat, and new drive belts) were only $290, so I figure I could save myself a ton of money by knowing how to use a wrench. I already saved myself $150 by changing the oxygen sensor in the truck myself. Not sure why the dealer wanted 1.5 hours of labor to basically loosen a bolt, but whatever. Any way, the reason the timing belt needs to be changed now is that this service is due at 105,000 miles on these Frontiers. Since the guy who owned it before me thought it had a chain, it never got done. His mechanic is probably an idiot, because the guy who sold me the truck took great care of it, that’s mostly why I bought it. Any way, the truck just turned 127,000 miles old and with the belts still not changed, I’m not risking driving the truck until it gets done.

Any way, the first step is completed as of yesterday, and the radiator and cooling fan of my truck are currently up against the wall in the living room (temporarily). A couple tricks here that I came across:

First of all, the cooling fan cowling has to be removed first. It kind of wraps around the cooling fan so I had to bend the cooling fan back a little to get it out. Once it’s unscrewed from the two bolts on the top of the radiator it’s not really a huge issue, it’s just a tight squeeze. Next is that draining the radiator is a pain. On the Frontiers, the cap is almost directly under the frame rail, so a funnel was needed and some coolant got on the frame rail and one of the rubber engine covers. I got as much of it off of those parts as possible.

Apart from that, just removing the two large hoses and the one little one connected to the coolant reservoir (making sure that the little hose doesn’t drop below the reservoir) and the two bolts on the top of the radiator will allow the radiator to be lifted almost straight out of the engine bay. I left the bottom hose on the radiator and detached it from the engine instead, to keep coolant from leaking out of the engine. The coolant was extremely dirty, and since I don’t know the last time the cooling system was flushed, I’m going to put enough coolant in to make it to the dealer and have them do it for me. Hopefully they’ll also dispose of the gallon and some of coolant I collected in a bucket.

Any way, after the radiator and fan cowling were out, it was fairly simple to undo the four bolts holding the fan. The next step is removing the accessory (drive) belts, which a friend of mine is going to help me with, since I’ve never done it myself. I don’t want to spend any more money! With the radiator and fan out, the drive belts are front and center in the engine bay.

Hopefully everything goes smoothly from here. If not, there’s a mechanic right down the hill from my apartment so I could just coast down there and have them fix whatever. Hopefully it doesn’t come to that, but it’s always good to have a backup plan in place.

PART 2!

I got the new timing belt in my truck successfully by following the following three threads at ClubFrontier.org

http://www.clubfrontier.org/forums/f46/timing-belt-3-3-v6-41630/

http://www.clubfrontier.org/forums/f46/timing-belt-question-56771/

http://www.clubfrontier.org/forums/f46/when-did-nissan-switch-belts-chains-56250/

On to the pictures! The first one was after draining and removing the radiator, including the fan cowling and fan. Coolant goes everywhere!

Next, I pulled off all the old accessory belts. The first tensioner pulley bracket was removed (the one for the A/C). The one for the power steering and water pumps is still attached, and also attached to this bracket is a hose going to the thermostat/water pump. This picture still has the alternator belt on but that’s pretty easy to take off. The alternator actually has its own tensioner, which is a nice piece of engineering.

These are some of the parts out of the truck in the order I took them off, from left to right. First was the top tensioner pulley bracket for the air conditioning compressor, then one of the hoses leading to the water pump, then the tensioner pulley for the power steering and water pumps (which I stripped a nut off of and had to order a new one. That will probably be mentioned again later), then the top cover for the timing belt.

This is what the engine looked like with these parts removed:

Then I removed the bottom cover for the timing bolt, all the screws for it (they’re different lengths so be careful), and the crankshaft pulley. DO NOT USE A JAW PULLER ON THE CRANKSHAFT PULLEY. There’s a chip off of mine from where I tried to do that. These pullers require a harmonic puller and two M6 x 1.00 x 80mm bolts to get it off.

Fun story here: The crankshaft pulley bolt is a bear to get loose. My buddy and I tried a breaker bar at first but then had to find an air compressor and a pneumatic impact wrench. However, without removing the air conditioning condenser, there was only about a quarter inch of room to maneuver the impact wrench. So when the bolt came off it shot the wrench into the condenser and we had a rough time getting it out. Also, the compressor was full of mud for some reason and it almost destroyed the wrench. And we had to tow my truck behind my buddy’s jeep to get it close enough to the compressor, which was fun because I live in an apartment. I should have taken pictures of how we maneuvered the two vehicles. It was impressive. Any way, here’s the parts I removed, minus the crankshaft pulley bolt (which is 1 and 1/16 inches):

This is what the engine looks like with the covers off. It still has the old belt, old thermostat, and old water pump on it.

This is what the crankshaft sprocket should look like. The picture is rotated 90 degrees clockwise, so the punchmark should be on the bottom right-ish.

Finally, a picture with the new thermostat (you can see the red RTV silicone I used), new water pump (it’s shiny), and new timing belt (it’s clean) on. Make sure to get a factory Nissan belt with all the markings on it. Also make sure to put it on in the right direction, I put it on backwards at first and none of the markings were lining up and I freaked out for a second, but then realized and switched the belt and everything lined up.

A few things to note here. First of all, don’t put the new belt on until the water pump and thermostat have been changed. Coolant will go everywhere, and coolant should not get on the timing belt. Also, part of the water pump sits behind the belt itself. I wanted to get the water pump off with the old belt on in case I jarred one of the camshaft gears but it’s just not possible. Nothing bad happened though so that’s good, and now I have a new water pump! Hooray. After this, I put the crankshaft pulley bolt in so I could turn the engine over a few times with the breaker bar to listen to make sure the engine was timed right. After I turned it over a few times, I started it up just to listen to it run, but only for about fifteen seconds. This will not hurt the engine at all, and it’s a good sanity check before spending the hours it takes to get everything back in.

Also, a torque wrench was needed to get the crankshaft pulley back in. It requires around 145 foot-pounds of torque which is a lot. We got it as close as we could, but could really have used a chain wrench to hold on to the pulley instead of one of the old accessory belts.

I think that’s all for now. I’ll put up pictures of the destroyed pulley bracket later on.

The idea on this one is to put my new slow cooker on the internet, so if I can’t make it home in time to turn it off and have a delicious dinner, I can log in to my apartment over an SSH tunnel and turn off my slow cooker from anywhere in the world. Great idea! Eventually I’ll be able to expand this to other devices. Maybe have my whole kitchen on the internet. Who knows?

The first step is to figure out how to interface with a computer’s parallel port. There are 25 pins on a standard parallel port, and eight of them can be physically controlled to be either 0 or 5 volts. And, as I’ve learned from previous projects, this is enough to operate a MOSFET and control fun things! So I can theoretically control eight devices in the kitchen. I’ll probably plug the kitchen light into it because it’d be easy after what I did to it already, but maybe Bradley’s coffee pot is next…

These ports used to be used for printers but are largely considered “legacy” now, so I will be using a 1996-era Packard Bell with a Pentium II to interface with various appliances. I installed Ubuntu 9.04 (I didn’t have a 9.10 CD but whatever, I’m just using a command-line interface) and then decided to try Python out. I found this page on Ubuntu Forums to start off:

Ubuntu Forums!

After messing around with Python for a little bit I found this tutorial which uses C:

Tutorial!

I had to change a couple of things with the source code but I think this is the route I’m going to take. I’m not the world’s strongest programmer but I think this will be enough. Eventually, I may go back and switch to Python because someone wrote a GUI to alter the pins on the parallel port. Any way, I have already been able to SSH into the computer I’m going to use to control the pins on the parallel port and am going to start wiring everything up this afternoon. Clemson’s iced over so everyone’s freaking out and not doing anything interesting, so this will have to do! But to be honest I’d probably be doing this any way. Electricity is awesome.

No project here, just some fun things I have been thinking about. The first one comes from Georgia Tech Craig, who sent me this website:

Only at Tech

Reminds me of a lot of things that I do and kind of makes me want to be a student at Georgia Tech. Which happens a lot more than I think people realize. After all, Clemson is just Georgia Tech lite, with women. Any way, this site reminded me of some things that I have done that were “only at tech” moments:

My roommate Craig (not from Georgia Tech) and I used to lift weights fairly regularly. He’s a bigger guy than me even though I’m about a foot taller than he is, and he can bench press slightly less than double what I can. So one night I spent the evening calculating our power-to-weight ratios to make myself feel a little better about this. Since I’m about 30 pounds lighter AND my arms are longer so I do more work since I lift the weights farther, I figured this would work out in my favor. Craig’s was 8 watts per kilogram and mine was 5.5 watts per kilogram, which I guess is good because it’s more than half of Craig’s.

The other good one was dealing with the doors in Riggs Hall, Clemson’s electrical engineering building. They all have signs that say “FIRE DOOR. DO NOT IMPEDE.” So I thought a good idea would be to spend an entire semiconductor physics class deriving the minimum required impedance of the doors.

And, not to go into too much detail, but I also just had a 20-minute conversation with a physics professor about deriving mathematically how much more attractive redheaded girls are than non-redheaded girls. We had this conversation in the library and got some fairly odd looks, but we now have objective truth backing up something normally subjective! So that’s a bonus. I love science.

Any way, the next project is going to involve wiring my slow cooker to the internet, so stay tuned! It’s coming along nicely so far.

The laundry room in our apartment is supposed to use some overhead fluorescent lights, but they are the long tube style and rather than go out and buy some more (our landlord is horrible, it’s APM if anyone is thinking of living in Tillman Place in Clemson) I decided to wire up a standard light bulb base to the light switch in the laundry room so we wouldn’t have to do the laundry in the dark. (Also, in this picture the bulbs had already been removed)

I scavenged the light bulb base from the lamp I built for my apartment in Charleston (that was a previous project and is on this blog), then found a long power cable meant for a computer and cut both ends off and stripped the black (hot) and green (ground) wires. Then I attached one side of this cable to the light bulb base. After removing the light switch cover to reveal the switch, I attached the green wire to the ground wire inside the wall. Hopefully every light switch fixture has a ground wire somewhere. I attached the black wire to the top of the light switch at the screw-type terminal. Normally, an electric device would be connected to black (hot) and white (neutral) instead of green (ground), but most switches only cut off the power going to the high side of the device, so having the white wire around is unnecessary. In this case, it looked like it was actually there in the wall but I was not sure enough to go grabbing at random wires that were deep in the wall. While the green wire is normally used for safety, as long as the electricity is getting back to where it came from, green or white will work just fine.

After reattaching the light switch to the wall and hollowing out some of the side so the power cable would fit, I hung the wire and the light bulb base from the shelves above the washer and drier. Tada!

That’s probably not up to code. ATTENTION FUTURE EMPLOYERS: If I’m working for you then I will do everything to code and it will be extremely safe. I promise. I’m just a poor college student who doesn’t want to pay for light bulbs.

Also, on a completely unrelated note, and mostly since I had the camera out already, here is my ukulele!