Tractor Tech

Which signal word(s) is (are) used to identify the most serious potential hazards that would result in a high probability of death or severe injury?

• Caution

• Warning

• Danger

Piston type hydraulic pumps:

• are much more efficient than gear and vane pumps at the same pressures.

• have lower high-pressure limits than gear and vane pumps.

• have higher rpm ratings than gear and vane pumps.

• are larger and more expensive than gear and vane pumps with the same flow capacity.

Use Teflon™ back-up rings:

• behind o-rings to prevent protruding into the small spaces between mating parts.

• only when o-rings are used in the static condition.

• on both sides of the piston o-ring of a double acting cylinder.

When diagnosing basic hydraulic pump problems, it is helpful to remember that:

• in open-center systems, the pressures varies, but flow remains near constant.

• in closed-center pressure-sensing systems, flow varies, but pressure remains near

  constant.

• in closed-center load-sensing systems, both the pressure and flow varies.

As related to filter types and ratings:

• micron rating is a measure of the openings or hole size of the filter.

• one micron equals 0.00001 inch.

• the higher the beta rating, the more efficient the filter is at cleaning.

• adsorbent filters are chemically treated to attract and remove contaminants.

Ring ridge:

• is that lower portion of the cylinder wall that does not wear.

• is that upper portion of the cylinder wall that does not wear and where carbon tends to

  build up.

• should be removed with a cylinder ridge reamer before pistons are removed during

  engine disassembly.

The center of gravity of a tractor:

• remains constant when loads are attached to the three point arms because the

  attachment points where the arms connect to the tractor remain constant.

• raises as the load in a front-end loader raises.

A Slow Moving Vehicle (SMV) symbol:

• on the rear of equipment indicates that the equipment should be driving 35 mph or less.

• should be installed with a triangle point pointing down.

• should have a highly reflective red inside triangle with a reflective orange outside edge.

When diagnosing electrical problems and using Ohm’s Law.

• Volts (E) = Amperes (I) x Ohms (R).

• Amperes (I) = Volts (E) / Ohms (R).

• Ohms (R) = Volts (E) / Amperes (I).

The American Petroleum Institute (API) established the following designation(s) for engine oils:

• “C” classifications for combustion ignition engines.

• “S” classifications for spark ignitions engines.

• viscosity ratings (measurement of oil fluidity at specific temperature)

• the maximum additives that can be added by the manufacturers.