A tachometer is an instrument that measures the rotation speed of an object in revolutions per minute (RPM). Machinery is designed to operate within a specific RPM range to avoid damage from heat, friction, or lack of lubrication. Tachometers assist where monitoring equipment rotation speed is critical to safe or precise operation. Think you know all there is to know about tachometers? Check out the 3 uses below and test your knowledge.

Engine Speed

Tachometers are most commonly used to show internal combustion engine speed in RPM. Tachometers have been most useful in cars equipped with manual transmissions. The tachometer helps the driver shift smoothly and choose the best shift points for power or fuel economy. Tachometers are less critical in modern automobiles due to automatic transmissions and computer controls that prevent over-revving and damage to the engine.

Propeller aircraft with internal combustion engines rely heavily on the tachometer for safe operation. Engine RPM is critical to airplane takeoff and landing. A pilot must monitor RPM in flight to maintain or change elevation and achieve the best propeller efficiency and speed. 

Power Take-Off (PTO)

Trucks and tractors can utilize a power take-off unit (PTO). A PTO unit uses engine rotation to power implements used for farming, construction, or other tasks. A splined shaft is usually connected to the transmission or directly to the engine to attach and power additional equipment. Some PTO units will have their own gearing to step up or step down engine RPM to the ideal range. A tachometer ensures the operator that PTO-driven equipment always operates at the optimal RPM. A PTO can power mechanical or hydraulic attachments, including:

• Farming Equipment
• Construction Equipment
• Refuse Trucks
• Recovery Trucks
• Road Maintenance Trucks

Hours Of Operation

While road vehicles measure engine usage in miles, other machines measure engine age and usage by the hours of operation. Many tachometers include an hour meter. The tachometer monitors the engine speed, and the hour meter records the total hours the engine operates. The hour meter may be part of the tachometer or a separate display. Engines used in the following applications are typically monitored for hours of operation:

• Boats
• Tractors
• Aircraft
• Generators

Our Best-Selling Tachometers

The list below is a small sampling of the most popular tachometers we have in our inventory. We carry well-known brands like Autometer, Datcon, Dynalco, ISSPRO, Murphy, Stewart Warner, and more. With over 60 years of experience in aftermarket parts, we can help you find the right tachometer for the correct application. 

• Datcom 0-4000 RPM 12v Analog Tachometer With Alternator Signal Input - Part # 103733
• Datcom 0-4000 RPM 12v Analog Tachometer With Hour Meter And Alternator Signal Input - Part # 103684
• Datcom 0-4000 RPM 12/24v Analog Tachometer With Hour Meter And Alternator Signal Input - Part # 71725-00
• Datcom 0-3000 RPM 12v Analog Tachometer With Hour Meter And Alternator Signal Input - Part # 103749
• Datcom 0-3000 RPM 12v Heavy-Duty Analog Tachometer With Hour Meter And Alternator Signal Input - Part # 103678
• Datcom 0-3000 RPM 12v Analog Tachometer With Hour Meter And Magnetic Signal Input - Part # 103680 (Dynalco Magnetic Tach Tape Recommended)
• ISSPRO 0-3500 RPM Mechanical Tachometer With Hour Meter - Part # R8599
• ISSPRO 0-4000 RPM Electric Tachometer With Microprocessor - Part # R8585M
• ISSPRO 0-3000 RPM Programmable Tachometer - Part # R8530M
• ISSPRO 0-3000 RPM Programmable Tachometer With Hour Meter - Part # R85305M

Premium Tachometers From PartDeal

Since 1949, PartDeal has specialized in stocking and sourcing hard-to-find parts for commercial automotive and truck applications. Why shop with us?

• Each of our team members has 10+ years of parts-industry knowledge.
• We serve OEMs, fleets, resellers, installers, dealerships, and exporters across the globe.
• We can help match obsolete parts and provide solutions to technical problems.
• We can create custom parts with your own branding. 
• Orders of in-stock items are processed and shipped the same or next business day.
• We are ready to assist you. Call us at (503) 802-1370 or email at support@partdeal.com.