Friday, April 29, 2011

Tungsten Carbide Mens Wedding Rings

Today was the Royal Wedding between Prince William and Kate Middleton.  Ahhhh I love weddings.  Thus the inspiration for this post about men's wedding rings. 

Recently it is popular for mens to get wedding rings made from industrial metals.  Many hi-tech metals, namely Titanium, has been the awe of many tech weenies.  As a kid, I would save my lunch money so that I could buy Ti bolts for my mountain bike.  It is only natural that when the time came to select a metal for a wedding ring many of my generation chose metals that were more personally precious and meaningful than gold/silver, or platinum. 

Diamonds are forever; or so they say.  That is why engagement rings are traditionally a metal band that houses a diamond.  The hardness of the precious stone represents the everlasting love between couples.  We won't go into the material value of such a stone and the ideas behind that.  This idea of everlasting was one thing that I considered when selecting a material for a wedding rings.  Titanium as some of you might know is known for being light, tough, used extensively in fighter aircraft, and found only on Russian soil.  Not quite a symbol of love.  In fact if you have ever seen a titanium ring which has been worn, you will notice that they do not appear to be everlasting and shiny at all.  Since Ti is relatively soft it is easily scratched and beat up.  Though this might be a more accurate representation of love and marriage, it is not the ideals that one thinks of when embarrassing the institute of everlasting love. 

If you have spent any amount of time in a machine shop you know that hardness is king.  Steel is used to cut aluminum.  High speed steel can cut regular steel.  But the boss of metals is tungsten carbide.  Not only is tungsten hard and heavy, it does not wear out under daily use.  A tungsten carbide ring will look just as shiny 10 year later as it did the day you said, "I do": forever. 

When selecting a ring, I wanted a two tone ring.  Tungsten rings are silver in color.  Dark grey tungsten is achieved by a anodizing process.  This process only colors the metal a few atoms deep.  Though hard, tungsten can still get micro scratches.  These small scratches typically do not show up and do not degrade the overall shininess of the metal.  However, when a layer of anodized tungsten is scratched off, the silver base metal will show through.  This results in a scratched looking surface. 

A solution to this two tone anodized problem is to inlay a darker material.  A common inlay material for tungsten carbide rings is ceramic.  Unlike your office coffee cup, hold on as I take another sip from mine, the ceramic used for rings is a much harder industrial ceramic.  This type of ceramic is commonly used in bullet prof vests as a ballistic plate.  Some claim that since ceramic is so hard, ones need to be careful with it, so as not to shatter the ring or inlay material.  This is false.  I have never been gentle with my ring and have not one blemish on it.   The ring in the picture above is the one that I wear.   It was purchased by my wife at a local jeweler.  A basic Tungsten carbide rings can be purchased for under $50.  Fancy ones can run up to $300.  The low cost of these rings is a welcoming figure in the high dollar world of weddings.  After all isn't love free. 

So now I wonder:  what type of wedding ring did Prince William get?

Wednesday, April 6, 2011

Subaru Outback O2 Sensor - PO130

Driving along you look down at the dash board and notice that the little check engine light is on.  What a sure way to spoil your day.  Immediately dollars signs flash as you wonder how much this is going to cost you.  If you do the work yourself and are careful with your diagnostics, not very much.  In my case it cost 62 dollars and a 6 pack of beer.  Our Subi is a 2000 Legacy Outback 2.5 Auto with 150k.

A few weeks ago I had such an event occur.  Since the car is newer than 96, it has an OBD II (On Board Diagnostic) system.  I drive home and plug it into my code reader , and out pops a PO130 code.  Cross references an on-line manual which states that I have a Front Oxygen Sensor circuit malfunction.  From some on-line reading on Subaru Fourms, circuit malfunction often means a short in the circuit, usually caused by water in the plug connection. Well that makes sense as right before the code was thrown I was getting the family truckster sideways in an parking lot with 3 inches of  slush on the ground.  So I cleared the message and waited for the car to dry out.  One thing to mention is that when the check engine light came on, it was steady and did not blink.  This means that you have an error message you should get it checked out.  If it was flashing it means that you are doing damage to the car, stop driving. 

A few days later the car develops a stumble.  Press on the gas and it barely runs.  Pull over and take a look at the engine.  Yep it looks like an engine.  Rev it a few times and everything is back to normal.  The check engine light never came back.  Over the next couple of days this stumbling issue happens a few more time.  It feels like the engine isn't getting gas.  I check the basics around the engine.  Gas in the tank, air intake not obstructed, fuel injectors ticking, spark plugs sparking, spark plugs look good, O2 sensor plug dry and secure, all oil levels full, no blown fuses  Over the next few days it also has several more stumbling episodes, and it throws another PO130 code which I clear out.  The last few instances was really rough,  engine even made popping sounds typical of super lean (low fuel) conditions, like the sputtering right before you run out of gas.  Somehow I must not be getting gas. 
I got a fuel pressure gauge and "T" it into the fuel line just down stream of the fuel filter.  Before unhooking any fuel lines you want to bleed off the pressure to minimize the amount of fuel you spray.  Leaving the car over night usually does it.  But pulling the fuel pump fuse or relay and cranking the engine till it dies is much quicker.  Unknown to many is that behind the knee panel compartment is a fuse bank. I removed the whole panel, but all that is required to be removed is the little flip out compartment. Locate and remove the 15 amp fuse at the top left.

The greatest diagnostic tool ever made is the Internet.  So I hit all the usual Subi Forums asking for advice.  Fuel pump, fuel pressure regulator, mass air sensor, coolant temp sensor, transmission temp sensor, and bad gas were allsuggestion.  At this point I had a bad O2 sensor codes appear twice now.  Why didn't I just change out the O2 sensor.  Well I was under the impression that other codes told you you had a bad O2 sensor (sensor reading out of range), and if the circuit was really bad, it would constantly have the check engine light on, not occasionally (every150 miles).

Before I go any further let us talk about O2 sensors and what they do.  Your car needs a mixture of fuel and air to burn.  Back in the carburetor days the carburetor mixed the fuel and air.  Since carbs only mixes the fuel and air to one ratio without consideration for varing conditions, fuel injection was developed.  The amount of fuel the injectors spewed is based on the amount of pressure in the line and the duration the spray nozzles are open.  Input signals from the Mass Air Flow/Pressure sensor determines the duration of the spray.  The O2 sensors read how much fuel is left unburnt in the exhaust and fine tune the mixture.  When one of the sensors is not working it sends the fuel map into a safety mode, erroring on the side of burning more gas than is needed (rich).  Running rich is safer cause the car will still run and you do not run the risk of detonation (blowing up your motor with a too lean of a mixture-this is a whole other topic).  This is why it waste gas when you have a check engine light on.  This is also why I figured a known O2 sensor issue will simply cause the car the run rich and not generate such a shortage of fuel condition, and thus not a result of the PO130 error message. 

Often times cars have two O2 sensors or more.  This can add a bit of confusion, as some are desginated as bank one and two and others as front and back.   In some "V" configured engines an O2 sensor might be present to monitor the left bank of cyclinders and the right.  In newer cars there is often O2 sensors located before and after the catalitic converter, its purpose is to monitor the condition of the cataletic converter.  I assume that it is possible to have a combination of such sensors and have four seperate O2 sensors for your car.  Our Subi has two sensors to monitor the condition of the cats, and does not have sensors to monitor the left and right bank.

The problem with my stumbling problem was that it was intermittent.  This makes diagnosing the issue difficult as it would not do in the comfort of my garage, only on the open road.  If it was my fuel pump or fuel pressure regulator I wanted to confirm it before I replaced it.  Nothing worse than replacing a part only to find that it was fine and not related to the issue.  This I call the "machine gun" way of repair; fire a bunch of bullets and hope to hit the right thing.  A working fuel pump will generate a constant and adequate fuel pressure.  If the pump is dying I would be able to tell with a gauge. 

With the fuel pressure gauge hooked up I drove it around the neighborhood for 30 minutes and no issue.  Dang.  The next day I drove it to work and finally the car started to stumble.  The fuel pressure was higher than spec and steady.  The fuel pressure regulator's job is to lower the fuel pressure to the specified amount. A vacuum actuate diaphragm restricts the amount of fuel which passes.  This is also how the FPR varies its regulated pressure.  As you stomp on the gas, less vacuum is available in the intake manifold, thus reducing the amount of fuel pressure reduction.  To check the FPR, pull the vac line.  The pressure should rise.  There should also be no fuel dripping out of the vacuum port, as that would indicate a ruptured FPR diaphragm membrane. 

I was now at a loss?  Do I start checking other sensors like the forum members suggested.  While driving home from work the car developed a stumble again.  Pull over and the check engine light comes on and the stumble went away.   The code read PO130, and  I did not clear it. I then proceed to drive the car for 50+ miles with out a hiccup.  I think I finally figured it out.  PO130 means that the ECU has received a grossly out of range signal from the O2 sensor for a steady duration of time.  Though often it means something is awry with the circuit, it could also mean that the sensor is completely dead.  An error message is then generated and the ECU no longer looks to the sensor for fuel mixture tuning.  When the error code was deleted the ECU still considered the sensor input (though grossly wrong) to mix the fuel, and did so incorrectly, causing a stumble.  The car sensing that it was not running properly, reverted back to a preset safety fuel mixture. 

Ok now that I concluded the source of my error, I needed to do some actual repair.  First I sourced the part.  Bosch has been known to make quality OEM replacement parts.  Bosch oxygen sensors are often times specified by the auto manufacture and used as original equipment.  I found a direct replacement part at the local Napa Auto parts store for about $60.  There are other cheaper versions of the sensor which require you to cut and splice your original plug connector.  No thanks. 

Now to remove the sensor.  First locate the connector plug on the passenger side of the engine. It has a light grey colored safety clip on it. Remember how the clip is attached cause it is tricky to get back on correctly.  Undo the clip and pull apart the connector.  Undo the wire keeper tab that is located a bit further down.

Most O2 sensor are a standard size, 7/8".  However it is not something that you can remove using a standard socket.  Due to the wire you need to use a tool similar to a flared nut tool.  I guess for removing the old sensor you can simple cut the wire off and use a deep socket.  Using a open end wrench only grabs the hex in two points and easily rounds out the hex.  The idea is to clear the wire but to engage more than two of the hex points. 

Though the subi uses a boxer engine with two separate banks, it uses only one O2 sensor for it fuel mixture reading.  The sensor is located at the "Y" portion of the exhaust as the two header pipes meet.  Because of the location I was not able to get my O2 sensor socket in.  Maybe if I had a crows foot type socket I could wiggle it in place.  But I did not so it was time to drop the exhaust. 

Of course in order to drop the exhaust the first thing that needed to be done was to drop the skid plate.  Next I undid the six exhaust header nuts.  The exhaust comes down but not quite far enough. I needed to go to the next exhaust hanger and undo the bolt.  Once the bolt is removed the hanger has a lip which the exhaust mounting bracket hangs from.  Lift the exhaust up past the lip and to the side to fully release the exhaust.  Be sure to have something support the exhaust.  The flex joint located downstream is not capable of support to forward section of the exhaust.  There is also the wires from
 the rear O2 sensor that will snap if required to hold the weight of the front exhaust portion.  Gently wiggle the exhaust when you lower it onto your support as the O2 sensor and wire stick through a heat shield and gets hung up.  As you can see in the picture I supported the exhaust on the catalytic converter with a block of wood on a floor jack.

Once you get to this point the rest is easy.  Undo the bad front O2 sensor and replace. Once removed it was obvious that the O2 sensor was toast, as it rattled with a broken part inside.  In the picture you can see the small threaded hole, or bung, that the O2 sensor fit in right at the "Y" portion of the exhaust.

Put the car back together again,  clear the error code, and be happy once again.   This is the part where you drink the six pack of beer to celebrate.

Friday, April 1, 2011

Harken Camper Shell Hoist

Those with pickup trucks usually fall into two categories; the ones that run a camper shell and the ones that don't.  Both have their benefits, both have their draw backs.  For many years I had a pickup truck with an open bed.  The ability to simply toss large items in the bed was one of the major draws of owning a truck.  But once you have a shell , it is hard to go back. The secure storage, shelter from the elements, and the ability to over load the bed without worrying about things flying out is nice.  However the shell does get in the way when you really need to transport large items in the bed.  Such a dilemma.

Camper shells however are not permanent installations.  They can be removed when you need to carry something that is too large for the capacity of the cap.  Though typically not to heavy, 100lbs or so, the large dimensions of the shell make it nearly impossible to remove and install by yourself.  Even with two people it can be awkward. 

A friend suggested that I buy a hoist system for my camper shell so that it would be easy to take on and off.  Taking the shell on and off was happening more often, now that transporting motorcycles became a regular thing.  Me, being the "do-it-yourselfer" of course looked into a homemade hoist system.  However once I found the Harken Hoister I knew that this was one of those things best left to the professionals.  From my years of sail boat racing the brand name Harken was synonymous to quality.  At a price of under $150 dollars, I knew that there was no way I could put together a system as good or as cheap as the one Harken made.  So I bought it.  At the heart of the system is the 8 to 1 block and tackle pulley.  This mechanical advantage device not only has all of the pulley nestled within itself, it also has a line lock, similar to that found on your mini blinds.  Of the many hoist systems Harken makes, the 200lb rated version was designated as the "camper shell" hoist. 

Prior to getting the hoist it is key to find a place where the hoist can pull the camper shell out of the way.  Carefully measure out the location as some spots which might look like it will work simply won't  As seen in the first picture my camper shell fits snugly between the back wall of the garage and the garage door opener.  It also sits high enough so that the back door of the garage can be opened without interference. 

The installation was pretty straight forward.  Though upon initial unpacking, the parts and lines are a bit over whelming.  The detailed instructions clearly lays out the steps required.  In addition to the parts included, you need to provide some 2x6s and some lag bolts.  It is recommend that two people do installation.   The most tricky part was to insure that cross member was bolted to the joist.  This isn't one of those things that will hold if bolted to the dry wall alone; you must sink ALL the lags into solid joist. 

Once installed the system perform flawlessly.  If you plan on leaving the shell in its hoisted position for any amount of time, it is a good idea to provide a safety back up.  Two fixed length of rope under the shell in case the buckles let go, and to securely tie off the primary hoist line in case the line lock gives.  Though I write this precaution, I have yet to add such safety back ups and had not had an issue. 

With this hoist I can now go from camper shell to open bed in less than 15 minuets.  A great addition to any truck owner debating a shell.  Now you can have the best of both worlds; thanks Harken.