Owning and Operating a Dynahoe 190-2 Backhoe Loader

[MikePhua]

The Dynahoe Legacy and Model Overview
Dynahoe was a brand of heavy-duty backhoe loaders originally manufactured by the Warner & Swasey Company, later acquired by Bucyrus-Erie. The Dynahoe 190-2, introduced in the 1970s, was built for industrial-scale excavation and land clearing. Unlike compact backhoes, the 190-2 was a full-sized machine weighing approximately 10 tons, powered by a Detroit Diesel 3-53 engine. Its rugged frame, oversized hydraulic cylinders, and deep digging capability made it popular among municipalities, contractors, and landowners with serious earthmoving needs.
Though production ceased decades ago, Dynahoes remain in use thanks to their overbuilt design and mechanical simplicity. Their cult following among vintage equipment enthusiasts has kept parts circulating through salvage yards, online groups, and private collections.
Terminology Annotation
- Detroit Diesel 3-53: A 3-cylinder, 2-stroke diesel engine known for its durability and distinctive sound.
- Hydraulic Cylinder Repack: The process of replacing internal seals and wear rings to restore pressure and eliminate leaks.
- Starter Solenoid: An electrical relay that engages the starter motor when the ignition key is turned.
- Fuel Canister Filter: A cartridge-style fuel filter used in older diesel systems, often requiring manual priming.
- Hydraulic Snowcone: A humorous term for a large spill of hydraulic fluid, often caused by a burst hose under pressure.
Initial Ownership Experience and Challenges
One new owner acquired two Dynahoe 190-2 machines—one primary unit and one spare. Both were running upon delivery, though the spare had leaky hydraulic pistons. On a cold day, the main machine refused to start, while the spare fired up after coaxing. After a few minutes of smooth operation, the spare stalled with the bucket suspended over a rock wall, requiring creative propping with a log.
Suspecting bad fuel, the owner began troubleshooting. Meanwhile, the main machine was started and tested, only to blow a hydraulic hose while lifting the front end. This resulted in a large fluid spill and two disabled machines in the yard. The experience highlighted the reality of owning vintage equipment: repairs begin sooner than expected.
Fuel System Troubleshooting and Cold Weather Tips
Older diesel machines like the Dynahoe 190-2 are sensitive to fuel quality, especially after long storage. Common issues include:

• Water contamination in the tank
  
• Algae growth in diesel fuel
  
• Air intrusion from low tank levels during transport
  
• Plugged fuel filters from sediment or microbial buildup
  

Recommended steps:

• Drain and inspect fuel filters (both low and high pressure)
  
• Check for water in the filter bowls
  
• Prime the system manually until fuel overflows at the bleed screw
  
• Inspect the fuel tank for rust flakes or debris blocking the feed line
  
• Use fuel additives like biocides or anti-gel formulas in cold weather
  

One operator added an electric fuel pump between the tank and filters to maintain prime and discovered a leaking seal at the back of the gear pump. This kind of diagnosis is common with older Detroits, which can suck air internally under load.
Hydraulic System Maintenance and Hose Replacement
The Dynahoe’s hydraulic system is robust but prone to leaks due to aging hoses and seals. Blown hoses are common when operators push the machine too hard or operate in freezing conditions. Preventive measures include:

• Replacing hoses with modern hydraulic-rated lines (avoid automotive fuel hose)
  
• Repacking cylinders with new seals (requires heavy-duty tools or professional help)
  
• Keeping spare hoses and fittings on hand for field repairs
  
• Using AW46 hydraulic fluid, available in bulk at retailers like Costco
  

One owner reported repacking three cylinders and repairing a crack between the bucket arms. Having a second machine proved invaluable for lifting and disassembly during repairs.
Starter Solenoid and Electrical Repairs
Cold weather and rushed repairs led to a snapped starter solenoid while tightening cables. The solenoid was replaced for $35, and the starter reinstalled with only two bolts—though a third was added later for security. These solenoids are often standard parts available at auto parts stores.
Electrical systems on Dynahoes are simple but vulnerable to corrosion and vibration. Recommendations:

• Clean all terminals and apply dielectric grease
  
• Replace cracked wires and brittle insulation
  
• Keep spare solenoids and relays in the cab
  

Parts Availability and Community Support
Service manuals for Dynahoe machines are rare, but parts books and operator manuals are still circulating. Online groups and forums offer diagrams, photos, and advice. Some vendors sell NOS (new old stock) parts, though prices can be high. Filters are readily available through NAPA and similar suppliers.
Having two machines allows owners to swap parts, test components, and perform repairs without downtime. This strategy is especially useful when dealing with large cylinders or hard-to-access components.
Conclusion
Owning a Dynahoe 190-2 is a commitment to mechanical problem-solving and vintage iron stewardship. These machines are powerful, overbuilt, and capable of serious work—but they demand attention, patience, and a willingness to get dirty. From fuel system quirks to hydraulic leaks and starter repairs, the learning curve is steep but rewarding. With community support, spare parts, and a second machine for backup, even a first-time owner can keep a Dynahoe running strong.