A Story Problem!

Nissan 350Z

Here's a Story Problem for you: 

Some guy, we'll call him "Brian," is driving his Nissan 350Z race car at 122.987mph from Chicago to New York, so if it's 789.9 miles, how many...

Step 1: unload car from trailer...

and Step 2: start doing stuff!

Oops, sorry! Wrong story problem! Try this real-world scenario: 

NMS-South wants to delete the AC from their race car. At the EXACT same time, NMS-North is enrolled in Air Conditioning Class that meets three hours per day Monday thru Friday. This is a two-part question: 

1) How long will it take NMS-North to remove the AC System (but not the evaporator)?

2) How much does NMS-South OWE NMS-North for removing said AC system? Let me repeat, there is NO WAY I'm pulling out the evaporator, because that would likely involve taking off the entire dash and adding hours to this job!

Condenser, no longer needed to cool refrigerant. Radiator fans sitting on it will go back in the car. 

1: Subtracting the classroom time that did not involve wrenching on the car, and the delay caused by waiting for parts to arrive (more on that later), it took 4 days. 

2: The most popular answer to this question came from one of my classmates, who said "He owes you a lot more than a cheeseburger!" so, I'm going to use that as the answer to every question I get for the next week. 

    Q: "Hey man, how do I get to Charlotte from here?" A: "A lot more than a cheeseburger" 

    Q: “Think it'll rain today?" A: "It'll take a lot more than a cheeseburger!"

AC machine, handy for removing refrigerant safely.

Step 1: To remove the condenser and AC, you have to first drain the refrigerant. Then, to get the radiator out of the condenser's way, you have to loosen it, get the two air boxes out of the way, get the upper radiator hose out of the way, and just for fun you might as well remove the tower brace and engine cover. Along the way I drained the coolant and later refilled it with distilled water when things were hooked back up. 

Step 2: To remove the compressor, take off the old belt, unclip the electrical connections, take off the two AC lines, and take off the three bolts holding it on. This step is pretty simple, once you find that last bolt way on the back of the compressor!

Compressor removed, no longer needed to compress and pump refrigerant.

Step 3: To remove a tiny bit more weight, I took out the first sections of AC lines that had gone from the condenser towards the evaporator. This is light weight stuff, but also included a few clamps and bolts along the way. With the high-pressure line, I used a special removal tool at a connection, but the low-pressure line didn't have any connectors easily in reach, so I used a set of diagonal pliers to just cut it off. After crimping the lines, no problem. The rest of the lines in and out of the evaporator can just sit there. 

This machine tests the refrigerant before you work on the system, so that you know what you're dealing with. Old cars might still have R-12, most have R-134a, and new cars have R-1234yf. 

Step 4: Now with no compressor to be driven by the serpentine belt, I could also remove an idler pulley that wasn't needed (diagram below.) Then, with one less pulley, you need a shorter serpentine belt. Brian researched what size belt would work in this new configuration, but when we tried (and tried, and tried) to fit it on the car, it was a bit too short. No problem, we ordered a slightly longer belt! Keep in mind that Nissan did not make any of these engines with no AC this way, so there is no "book" answer length of belt to buy.

Your basic Before and After, although since this diagram is for a 370Z, we don't have the idler pulley that is the farthest to the left.

 THIS Idler pulley? Fughgeddaboudit!

However, belt number two was too long, and this is where this story turns into a variation on Goldilocks and the Three Bears, because I was really... really... REALLY hoping that the THIRD BELT would be JUUUUUSSSTTT right! And it was!

New shorter belt, no AC and one less idler pulley.

After getting the right size belt on, and putting all the parts back on, it was time to fire it up! Guess what? No problems! After running a while, the fans kicked on like they are supposed to, there were no coolant/water leaks, and the belt kept doing its thing in a shorter size! 

So, that's the end of our story problem for today. NMS-South now has a car with deleted AC, NMS-North got to work on a racecar for four days, and certainly the world must be a better place for it! Thanks for reading!