Monday, December 9, 2013

FQ Hans

This week I was reading about the type of crown gear uses in the differential of the international truck that I took apart. The type of gear set used is a hypoid gear. In this type of gear set the pinion gear drives the crown gear from below the center of the crown gear. This gives hypoid gears a greater torque capacity. These gears drive forward on the convex side of the gear teeth. The characteristics of a hypoid gear allows it to run quieter and makes it stronger.

Wednesday, December 4, 2013

Alignment

This week I learned how to set the alignment on a truck using "The common man's guide". The first step is to set the toe. When doing this you should drive the truck forward in a straight line so that it is sitting how it would be driving down the road. Then you check the toe by placing a bar on each wheel and taking a measurement from bar to bar. The measurement between the front wheels should be 1/16" les than the rear so that you have 1/16" toe in. The toe can adjusted by turning the bar that connects the tie rods.

Monday, December 2, 2013

FQ Hans

This week I pulled a diffential out if an international truck. I pulled it out because it was making grinding noises and wasn't sending power to that different.

Wednesday, November 27, 2013

FQ Hans

This week while working on a tractor that was getting coolant into the number 1 cylinder, I had discover that there was a gap between the cylinder liner and the block. The cylinder liner is supposes to be a .004" interferance fit and there was a .003" gap in a couple spots. Its my suspicion that the block is cracked around the liner and allowing coolant up through the liner.  I came to this conclusion because the cylinder head has no cracks and passed a pressure test so that means it has to be in the bottom end. The deck on the block is within specs for being level.

Tuesday, November 19, 2013

ABS modulator valve

The clicking noise from the wheel end on the Freightliner truck in the shop is the ABS modulator valve running a self check on its self to check the operation of the relay. This is a Bendix part and the part number is 550414 and its a M-21 modulator. This modulator works by getting a signal form the wheel speed sensor, when the wheel speed sensor senses the wheel is about to lock up, and it exhaust the air pressure going to the air can on the wheel that is going to lock up.

During normal braking application both the exhaust and supply solinoids are deenergized. when the brakes are applied air pressure, going to the service brake chamber, seats the exhaust diaphram on the exhaust port along with the aid of spring pressure. When wheel lock up is detected the antilock controller simoltaniously sends power to the exhaust and supply solinoids. Power is sent to the exhaust solinoid to open the exhaust diaphram and give the air from the brake chamber a path to escape to the atmosphere, so that there will be no braking force on the wheel that is about to lock up. Power is sent to the supply solinoid to close the supply diaphram so that air wont be allowed to flow to the brake can.

Monday, November 18, 2013

FQ Hans

This week I put some fittings on DOT air lines used on trucks. These fittings use a feral to seal them when the two ends are screwed together

Monday, November 11, 2013

FQ Hans

This week I adjusted a wheel bearing on the kenworth in the shop. I used the TMC procedure to adjust the bearing. The procedure for this is to 1. Tighten the inner nut to 200 ft lbs to seat the bearing. Then 2. Back off the inner nut one full turn. Next 3. Torque the inner nut to 50 ft lbs. Then 4. Back the inner nut off 1/4 turn. Then you can install the washer and the outer nut. Finally you torque down the outer nut. The torque of the outer nut is dependent on whether it is a drive or steer axle, how many threads per inch it has and what type of washer it uses. In this case the finally torque was 300-400 ft lbs. Once that is done you can place a dial indicator from the wheel hub to the axle nut and move the hub back and forth to measure endplay. Endplay should be between. 001-.005 of an inch. If you have a reading of zero, the adjustment needs to be redone because then you don't actually know how much preload is on the bearing.

Monday, November 4, 2013

FQ Hans

This week I was testing on my truck why the turn signals on the right side would blink faster than the turn signals on the left. It was pretty obvious that the relay for the turn signal flashers was going bad. I had also found out that the way the bulb for the turn signals in the tail lights goes in makes a difference. The bulb for the blinker is also a bulb for the tail lights and brake lights. I had put a bulb in the wrong way on one of them so you could see the turn signal light when the tail lights where. So after I saw that was going on I tested to make sure I had proper voltage and the I looked at the bulb and realized the filaments were different sizes. So I switched the bulb around and it worked fine again.

Week = 51 , total = 260

Monday, October 28, 2013

FQ Hans

This week I learned about adjusting wheels bearings using a dial indicator. You want your wheel bearing to have .001-.005 inch of endplay. There is also a procedure that was created by the technical and maintenance council uses to adjust wheel bearings. This procedure makes it very simple to adjust wheel bearings with the correct amount of endplay.

Tuesday, October 22, 2013

FQ Hans

This week I got to take the head off of a tractor because it was getting water into the oil, water into the cylinders and blowing compression into the cooling system. This was a pretty easy head to take off because all you have to do is take the hood off of the tractor and there is nothing in your way to pull the head off. The rocker arms also come off as one assembly so you just have to loosen the head bolts that hold them on and pull off the rocker arms for all four cylinders as one unit. Now I just have take the head to a machine shop to make sure its not cracked and to make sure its not warped.

Monday, October 14, 2013

FQ Hans

This week I learned about performing starting and charging test with my multimeter. I actually ended up getting a chance to use these test on a 1984 Chevy pickup to figure out why the starter would crank slowly and sometimes start and sometimes not. I knew the battery was brand new so I didn't think that could be the problem. After testing I knew I had good connections and minimal voltage drop and 10 volts while cranking. So I did a voltage drop test on the starter solenoid and had .3v of drop so I knew the solenoid was fine. The only thing left that it could be after that was the starter so I replaced it and the truck now starts almost instantlly after turning the key.

I took the old starter apart to try and figure out what was wrong with it and after looking at all that I could tell was there was a wire inside of it that had some broken strands and corrosion on it.

This week = 55,  total =  107

Wednesday, October 9, 2013

FQ Hans

This week I learned about finding parasitic battery drains using an amp clamp and multimeter. You can use the amp clamp to measure the amount of current being drawn and then use a multimeter to measure the voltage drop across a fuse in millivolts to find where the draw could be coming from. If there is a voltage drop then you know that there is current flow.

Hours = 52

Monday, August 26, 2013

Summer quarter Hans

This week I finished up working on my 1989 chevy 3500 installing new main bearings, rod bearings, and an oil pump. Since the engine has to be lifted up to get the oil pan off the engine, I decided that I was just gonna pull the engine out of the truck and put it on an engine stand to make working in it easier.

Monday, August 19, 2013

Summer quarter Hans

This week I spent a lot of time greasing the trucks and trailers in the fleet. I leaned a lot about looking for broken things on trucks. Some things you find are more obvious than others, like a brake can on a trailer with broken studs so it was only hanging from the air lines and the slack adjuster.

Tuesday, August 13, 2013

Summer quater Hans

This week I was reading article in a magazine that was talking about brake cleaner. The article was titled Poisonous Gases in Your Shop and in it the writer was saying how you really need to read the warning labels on the chemicals that you use. The writer talks about an experience that he had with brake clean and how it almost cost him his life. One of the warnings on brake cleaner is "Vapors may decompose to harmful or fatal corrosive gases such as hydrogen chloride and possibly phosgene". When the active chemical in brake cleaner, tetra-chloroethylene, is exposed to extreme heat and along with being in an argon purged enviroment from welding, it produces phosgene. The authors story was that he was using brake cleaner to clean some heavily pitted aluminum before welding it and he had thought the he has gotten all of the brake cleaner off of the metal. When he was welding he came upon a heavily corroded pitted area but there was still some brake cleaner in the deep pit and this caused a small puff of white smoke that was phosgene gas and almost caused an end to his life. In the article it says that phosgene gas can be fatal with a dose as little as four parts per million. Because it is a nerve agent symptom can be delayed 6 to 48 hours. There is also no antidote for phosgene poisoning and if you do survive it can cause chronic health issues. I think that this is a good warning to be careful with how we use the chemicals that we use.

Week = 50, total =273

Monday, August 5, 2013

Summer quarter Hans

This week I was working on a 2000 Dodge pickup trying to figure out why the power windows and the blower motor weren't working. At first I tested the switch to making sure it had power going to it and it did, but after I looked at the wiring diagram that we had I found out that was the power wire for the door locks and not the power windows. So then I  started checking the fuse and it was good. Then I looked at the wiring diagram to see where the wires for the windows go to but that didn't help any since we didn't have a very good wiring diagram. Since we knew the windows and blower motor only work while the truck is in the run position one of the guys suggested that I check at the ignition switch. So after u got the plastic covers off the problem was very easy to see. The wire that sends power for the power window and blower motor had pulled apart from the connector, which had most likely happened cause of how tight the wire was when the tilt steering was put all the way up.

Week = 52 ,  total = 223

Tuesday, July 30, 2013

Summet quarter Hans

This week I replaced a spindle and steering arm on a 2009 new Holland t4030 tractor. The steering arm and spindle were starting to get a lot if slop in them where they bolt together and this tractor only has 2500 hours on it. The only reason that I can think of why this happened is because that was the side that has the hydraulic cylinder connected to it for the steering. So my guess is that the pushing and pulling from the steering cylinder puts a lot of strain on those parts. This type of tractor also doesn't seem like it was designed to see real use on a farm and seems more like it was made to be a hobby tractor. These tractors certainly aren't made like they used to make the old fords.

Monday, July 22, 2013

Summer quarter Hans

This week I got to rebuild some brake calipers on a Volvo A30D haul truck. This is something that takes patience to do to get the inside of the calipers cleaned out of any rust that builds up in them.

Week = 56,  total = 123