Custom Tool Box Table (5/30-6/3)

We had a slow day at the shop and I asked if I could use some scrap aluminum to make a table for my tool box. My shop lead was fine with it so that I could get more practice with aluminum welding. After making the measurements my lead gave me some advice to set the support arms that were going to be welded on an eighth of an inch smaller than my measurement to compensate for the welder pulling the metal. Seeing as my box is too thin to tap for bolts I got to learn how to use a thread insert gun to use mounting bolts. Fun little project and got to practice aluminum welding. 



Hours: 40
Running Total: 342

Tank Removal/Valve Rebuild (5/23-5/27)

We serviced a truck this week that had a unique issue. The truck had a 750 gallon tank with a foam cell that contained 100 gallons of foam concentrate. The truck was found to be overweight by the area standards where the customer had the truck in service. They requested a new tank to be created at the factory that held 250 gallons of water less to meet the weight limit. I was able to help removed the old tank. This process included completely disconnecting the pump housing from the tank as well as fabricating a custom welded hoist to remove the tank. Cool project.





Our massive drill press with a 1 1/4" drill bit...
 


I also got the opportunity to rebuild leaking discharge valves on a truck that came in for service. To diagnose this we charged the pump with shop air and discovered a few leaks including the #2 discharge valve on the pump. Over time the ball valve in the valve housing wears down from debris in the water scoring it in addition to hard water breaking down the seals. It's a pretty easy but fun process of removing the valve to rebuild it, a very satisfying end result I might add.

Hours: 40
Running Total: 302

Poly Welding (5/16-5/20)

Couple of cool projects that week. I had the opportunity to an old aerial truck. It is a 75' ladder than extends by means of a series pulleys with steel cables all being pulled by a hydraulic motor. A section of the the ladder had some steel cable that was beginning to fray and needed to be replaced. In order to access the cable the ladder was fully extended down the length of the shop and supported by a stand at the end of ladder in case the trucks hydraulic stands failed.




We had a slow day that week and my shop lead to advantage of the time to train me to plastic weld. A lot of the trucks we service have poly plastic tanks and will require repair from time to time. As with all welding surface preparation is key, the surface must be buffed out an clean as possible. The equipment is essentially a glue gun on steroids. After the gun pre-heats a rod is inserted in the tip of the gun and with steady pressure and speed a pass is made along the two pieces of poly plastic are joined together. Pretty straight forward process.

Hours: 40
Running Total: 262

Week 6 (5/9-5/13) Pump Overhaul

Started my new job and first day found myself helping the shop lead remove and rebuild a pump out of a truck. The pump was leaking according to the operator. Upon removal of the outboard bearing cap housing we found water had made it past the seal and ruined the bearing on the discharge side. The pump relies on packing to seal water inside the pump rather than a mechanical seal. The problem was that the packing inside of the stuffing box had overheated and become a solid black mass allowing water to seep by. We replaced the stuffing box and installed new gaskets and o-rings.

The advantages to using packing vs a mechanical seal is that packing is more user friendly and are more robust against hard use. Mechanical seals a very sensitive and can be damaged very easily while installing them in addition to being more at risk to wear and tear by untrained operators.

Fire Truck! 

Pump Compartment (Half of pump removed)

Stuffing Box

Hours: 30
Running Total: 222

Week 5 (5/2-5/6) Hydraulic Steering

We have a piece of equipment with hydraulic steering. The operators are complaining that there is a delay in the steering followed by a suddenly turning sharply. After pulling it into the shop we found that there was indeed a delay in the steering but not sharp grab. We attached our pressure gauge and found the system to be operating within manufactures specs for pressure. The filters have been changed recently and the system is not contaminated as far as my co worker and I can see. Would this delay be due to the directional valve in the steering wearing out over time? The equipment is almost 30 years old.

Hours: 40

Running Total: 192

Week 4 (4/25-29) Cold Start System

We noticed a piece of equipment having a difficult time starting for the operators in the morning. We pulled it in the shop to check the starting system. We started with the glow plugs. I placed my meter on the glow plug railing and found a good ground. I found that I got no voltage to the railing. So I placed the meter on the first plug in the circuit, nothing. I then Attached my meter to the supply wire for the plugs and found a healthy 12.7V. I pulled the first glow plug in the circuit and switched my meter to ohms and found that it read a healthy OL on the screen. A new set of glow plugs later and it starts beautifully every time.

Hours: 40
Running Total: 152

Exhibit A

Problem Child

Railing 

Week 3 (4/18-4/22) Headlight/Belt

While checking one of the pieces of equipment I found that one of the headlights was out. So, naturally, I figured the bulb was bad. I opened the housing and tested the post that connects to the jumper wire that feeds the bulb and found 12v. Bulbs bad! After installing a new bulb I was disappointed to find that it was still out. Bulb was good... I figured out fairly quickly after that with some closer investigation that the jumper wire was completely corroded inside as I did not have 12v coming out the other end of the wire. So after kicking myself in the butt and listening to my coworker make fun of me for a minute or two, I replaced the jumper wire and now the bulb works just fine. Lesson learned, go to the LOAD and work your way back.

Also got to replace some belts on the push back, not too exciting but it's fun to work on and thought I'd post some pics.



Hours: 40
Running Total: 112