Day 33 Sheet

1. Antifreeze and water, being two different substances that absorb heat at different rates, should be considered in cooling system process. Antifreeze when mixed with water becomes less able to absorb heat. Specifically the loss in capability is about 1 degree Celsius for every 10% of glycol. This ratio will continue up to 50%.

2. Detonation occurs in the cylinder when the “end gas” or unburned fuel air mixture from the primary ignition will self-ignite at an imperfect or wrong time. A number of things play a part in the cause of detonation including fuel quality, compression ration, engine timing, intake air temperature, and aftercooler temperature. The “ping” or “knock” you hear when detonation is occurring is caused by the two leading edges of ignited flame colliding.

3. Along with the regular fluid change intervals a fluid sample, like the SOS of Cat, can be performed to analyze wear and quality of fluid.

4. Combustion air flow requirements will vary, depending on the specific engine model and rating. Specific air flow data for Caterpillar engines is given in both volumetric and mass flow terms, at standard reference conditions.

Sensor Testing

Today I was able to test a Cam position sensor for 2003-2009 International 6.0L/6.4L

Given the sensor i was not told anything about it but yet had to figure out how it worked and if it worked. What i came up with is that it was a position sensor due to its magnetic field. Using a Multimeter and test leads I found something interesting.

It carried .839 Ohms normally. As i stuck a piece of metal to it it jumped for a split second and returned to .839. When i notice a change in the reading was when i pulled the metal from the sensor it jumped to 1.4 ohms. Interesting...

After doing more research online I did find out that position sensors will actually create an alternating current sine wave in the form of a square.... this is what speaks to the ECU which then controls ignition timing, etc.

Below are some pictures of the sensor and my testing.

Thermo-STUCK

After taking all three thermostats, recording what i thought the opening temps were and submerging in water i realized that #2 was open and i wast sure when that had happened. At that point I took all three thermostats out of the water and submerged them in cold to see if i could get #2 to close again. I had no luck their, thermostat number 2 was stuck open.

This is the info i came up with for thermostat 1 and 3.

#1
Estimated open temp: 95 degrees C

Actual open temp: 90 degrees C
                             195 degrees F

#2
Estimated Open temp: 180 degrees C

Actual Open Temp: 85 degrees C
                              185 degrees F

I found that attention to detail is important! i didnt pay close enough attention to notice the thermostat that had opened and it had stuck. I also estimated the wrong degree for thermostat #2. Even though the number read on the thermostat did have a C by it, it was not signifying Celsius.

Books?

A point of interest last week, among other things, was some of the reading I was able to do about hydraulics. I knew some hydraulic stuff is going to be coming up and I wanted to get ahead. After watching the lethal strike I continued my reading in the heavy duty truck systems textbook. I studied about the basic concepts of a system and incorporated the mathematical requirements in square inches of the f pump and the cylinder. It's basic math! But to get an idea of what's all needs within a system was good to know. B

The Lethal Strike

WOW....

I had no idea the amount of the severity of high pressure hydraulic lines. I had a basic understanding that the contents under pressure could cause some injury to the skin, even to the point of losing fingers or entire body parts, or worse! I was thinking about posting some pictures with this blog but decided against it, NASTY!

The Lethal Strike video i thought was done well and informed in a way that almost scares you into taking the proper precautions when dealing with high pressure lines. It definately opened my eyes to the dangers and I can garuantee the next time im working with high pressure lines, even if there is no pressure built up, I will be remebering this and being extremely cautious. The one thing that really shocked me is at that amount of pressure leather gloves or the like would be penetrated as well as the skin of your hand or body. Even amounts as low as 100 PSI can cause hydraulic injection.

Im glad i watched this video, and I almost feel like any mechanic or hydraulic repair individual should most definately watch this video or be informed of the dangers before attempting to mess with this stuff. The only regret i have is not watching this sooner in my mechanical career. I have been in hydraulic line repair and even had one burst on me on a D4 Cat. Luckily my hands were not in the line of fire.... evidentally i got pretty lucky.

Mercedes Benz

This last week was spent mostly in Ye Mercedes Benz disassembly. By the end of the week we had the motor completely taken apart down to a bare block. One thing I spent a bit more time on studying was the fuel injection system and fuel injection in general. I feel I have a greater grasp of how these different systems work but would love to get even a greater understand I all of the different types of systems. Below are some pictures of the tear down.

Class/shop: 19
Work:25

Dive in!

This week consisted of a few new thing learned with using the scan tool to see the graphing of electric motors. I can definitely see the use of this tool being a huge advantage in diagnosing. I've used them before he never used them to the full capacity as I was able to do this week.

We were also able to drive the dodge 3500 around the block a few times after the new injector pump and fuel pump were fixed.... That could be a fun truck!

My highlight of this week was getting started on the Mercedes Benz disassembly. We were able to find quite a bit of info on the tear down process. I'm excited to reassemble and follow procedure on all aspects. This thing had got close to 900 lbs/ft web it's operating! Dang!