Tech Updates

Tips for servicing lighting and Electrical Systems

Truck-Lite Co., Inc. offers technicians the following tips when servicing lighting and electrical systems:

• Never use a test probe to pierce wire insulation. Wicking action takes place, which causes moisture to travel along the wire strands and corrode critical components. If you have to probe a wiring harness, make sure the puncture is sealed properly.

• Test all lamps before discarding them. Up to 20 percent of all lamps that are sent back to Truck-Lite’s warranty department still are in good operating condition.

• Treat the electrical system as you would the chassis. Lubricate sockets, pigtails, battery terminals and connections with NYK 77 non-conductive, anti-corrosion compound. The purpose of the sealant is to totally encapsulate and protect against corrosion and water.

• Always replace wiring, trailer light cables and harnesses with an equal or heavier gauge of wire than was used on the original specification. If you don’t, you may cause unnecessary problems. n

Hubodometer and Bracket Installation

Stemco provides the following information on the proper way to install hubodometers and brackets:

* Install the hubcap with the proper gaskets and installation methods provided by the hubcap manufacturer. Split washers are recommended to lock the flange bolt in place.

* Add lubricant to the proper fill level.

* Mount the hubodometer to the face of the bracket. Use a washer under the locknut (as shown in Figure 1).

* Use 15 ft.-lbs. of torque to tighten the locknut. Do not use an air impact wrench and do not exceed 15 ft.-lbs. of torque.

* If necessary, use a strap wrench to hold the hubodometer while tightening the locknut.

* Do not use paints, solvents or thinners on the hubodometer face, Grilamid hubcap or hubodometer hubcap

window.

* Remove necessary bolts for bracket installation. Note: some lubricant may drain out. Refill as needed.

* Mount the bracket and hubodometer assembly. Split washers are recommended to lock the bracket bolts in place.

* Torque the bolts to the recommended hubcap specification. Refer to Figure 2 for Stemco’s hubcap bolt torque specifications.

The recommended torque for the 3⁄8-inch pipe plug for aluminum hubcaps is 9 ft.-lbs. A suitable sealant may be used on the pipe plug thread if desired. On Grilamid hubcaps with plastic fill plugs and O-rings, torque should not exceed 10 ft.-lbs.