troxlerlabs.com: Gyratory Compactor FAQs

•	Why are my gyratory specimens not matching specimens of another gyratory?
•	What kind of basic maintenance can I do to my gyratory?
•	Why are my gyratory specimens coming up at 135-140mm when they used to be 110-115mm?
•	The printer for my model 4140 is not working or is printing strange characters?
•	The outlet on the back of the gyratory is not working (printer is not turning on)?
•	General calibration problems
•	Zero Angle System Deactivation Procedure

* For additional information, refer to the troubleshooting section of the Operator's Manual (4140, 4141).

Why are my gyratory specimens not matching specimens of another gyratory?
Check the preheat temperature of molds and hot-mix-asphalt (HMA). Make sure they have been heated up to the same specified temperature. Low mold and/or HMA temperature will cause lower compaction. Make sure the HMA is covered while preheating the mix. Uncovered mix will not compact as well.

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What kind of basic maintenance can I do to my gyratory?
Grease cam followers daily using Teflon based lubricant such as Magnalube-G (a can supplied with the gyratory). Keep gyratory clean of binder build up. Clean the ram head, and molds daily and cam followers weekly using WD-40. Remember to re-grease cam followers after cleaning.

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Why are my gyratory specimens coming up at 135-140mm when they used to be 110-115mm?
Make sure you calibrate the height using mold's bottom puck under the height standard. Leaving the bottom puck out will cause a 25mm error in the height reading.

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The printer for my model 4140 is not working or is printing strange characters?
Make sure to plug the printer into the outlet on the back of the gyratory (not into a standard wall outlet) and make sure the printer's On-Line light is on.

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The outlet on the back of the gyratory is not working (printer is not turning on)?
Check and replace the fuse for the outlet.

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General calibration problems:

•	Check all cable connections
•	Check the calibration equipment power connection
•	For the 4140, ensure that the height standard (for height calibration) and the load cell (for pressure calibration) are centered on the turntable
•	For the 4141, ensure that the height standard (for height calibration) and the load cell (for pressure calibration) are centered on the ram head and then offset approximately 1/4 inch (6mm) toward the rear of the chamber

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Zero Angle System Deactivation Procedure
The following procedure describes the deactivation of the zero angle screw system in the 4141 model compactor. It has been determined that disabling this system will have no adverse affects on the operation of the 4141.

The 4141 has three (3) ZERO ANGLE screws that are threaded shafts with a pulley mounted on top. A motor with a pulley drives a rubber belt that drives the three screws down and up.

1.	Turn off power switch and remove power cord and printer cable.
2.	Unscrew the three bolts from the top plate of the 4141 and remove the top plate.
3.	Unscrew the three black plastic handled bolts from the top of the electronics module (hereafter referred to as ELMO) and set them aside.
4.	Unscrew and unplug the three (3) cable assemblies on the ELMO (one near center top and two near power switch).
5.	Grasp the two handles atop the ELMO and lift it out of the 4141.
6.	Look down in the area below where the ELMO was and to the left rear to locate the belt drive motor. Locate the short (2 inch) red jumper wire on this motor and unplug it. Use a knife or cutter to cut the drive belt and discard it.
7.	Look inside the sample chamber at the ceiling to make sure all three zero angle screws are fully up. Use a wrench to loosen any that may be stuck and screw them up until they are not down any inside the chamber.
8.	Re-install the ELMO and reconnect the three cables. Install and tighten the three plastic handled bolts.
9.	Bolt on the top plate and reconnect power and printer cables.

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