Cub Cadet Rt65 Problems

Cub Cadet RT65 Problems: Troubleshooting Guide for Common Issues

The Cub Cadet RT65 rear-tine tiller has been a reliable workhorse for many gardening enthusiasts and agricultural professionals. However, like any mechanical equipment, it can develop problems over time.

Whether you’re experiencing starting difficulties, transmission issues, or tine performance problems with your Cub Cadet RT65, this comprehensive guide will walk you through the most common issues and their solutions.

Understanding these problems can save you time, money, and frustration, ensuring your tiller remains a dependable tool for your soil preparation needs.

Key Takeaways:

Most Cub Cadet RT65 issues relate to the engine, transmission, or tines
Regular maintenance can prevent many common problems
Fuel system issues are often behind starting difficulties
Transmission problems typically manifest as movement or engagement failures
DIY solutions exist for many issues, but some require professional service

In brief: The Cub Cadet RT65 commonly experiences issues with its starting mechanism, transmission system, tine operation, fuel delivery, and carburetor. Most problems can be resolved through proper maintenance and troubleshooting steps outlined in this guide.

Common Starting Problems with the Cub Cadet RT65

One of the most frustrating issues with the Cub Cadet RT65 tiller is when it refuses to start, especially when you’re ready for a day of gardening. Several factors can contribute to starting difficulties with this machine.

Spark Plug Issues

The spark plug is often the culprit when your RT65 won’t start. Over time, spark plugs can become fouled with carbon deposits or develop gaps that are too wide for proper ignition. To check your spark plug:

Disconnect the spark plug wire
Remove the spark plug using a socket wrench
Inspect for signs of carbon buildup, oil fouling, or electrode damage
Check the gap using a gap tool (should be between 0.020-0.030 inches depending on your model)
Clean with a wire brush or replace if necessary

A new spark plug costs only a few dollars but can make the difference between a tiller that starts immediately and one that won’t run at all.

Fuel System Problems

Fuel-related issues are another common reason why your Cub Cadet RT65 might not start. This can include:

Stale fuel: Gasoline that has been sitting in the tank for more than 30 days can break down and create deposits that clog the fuel system
Water contamination: Moisture in the fuel tank can prevent proper combustion
Clogged fuel filter: A blocked filter restricts fuel flow to the engine
Fuel line blockages: Debris or deteriorated fuel line materials can obstruct fuel passage

To address these issues, drain old fuel and replace it with fresh gasoline. Adding a fuel stabilizer is recommended if you don’t use your tiller frequently. Inspect fuel lines for cracks or blockages and replace the fuel filter annually as part of your maintenance routine.

Carburetor Complications

The carburetor mixes air and fuel in the proper ratio for combustion. When it malfunctions, your RT65 will struggle to start or run properly. Common carburetor problems include:

Clogged jets from fuel deposits
Improper adjustment settings
Damaged gaskets causing air leaks
Stuck float mechanisms preventing proper fuel flow

A thorough carburetor cleaning often resolves these issues. For cleaning, you’ll need to:

Remove the air filter and housing
Disconnect fuel lines and linkages
Remove the carburetor from the engine
Disassemble carefully, noting the position of all parts
Clean all passages with carburetor cleaner
Reassemble with new gaskets if necessary

For persistent problems, a carburetor rebuild kit or replacement may be necessary.

Transmission Problems and Solutions

The transmission system in the Cub Cadet RT65 is crucial for transferring power from the engine to the tines. When transmission issues occur, they can significantly impact the tiller’s performance.

Difficulty Shifting Gears

Many RT65 owners report problems with gear shifting, often manifesting as:

Resistance when trying to change speeds
Gears that won’t engage properly
Jumping out of gear during operation

These issues typically stem from:

Low or degraded transmission fluid
Worn shift linkage components
Internal gear damage
Improperly adjusted linkage

To address shifting problems, check the transmission fluid level and condition first. The RT65 requires specific transmission oil, and using the wrong type can cause issues. Inspect the shift linkage for loose connections or worn parts, and adjust according to specifications in your owner’s manual.

Transmission Slipping or Not Engaging

If your tiller’s transmission slips or fails to engage, you might notice:

The engine running but tines not rotating
Intermittent power to the tines
Loss of power during operation

Common causes include:

Belt issues (worn, loose, or broken)
Clutch problems
Internal transmission damage
Low fluid levels

For belt-related issues, inspect the drive belt for signs of wear, glazing, or damage. The belt should have approximately 1/2 inch of deflection when pressed. Adjust tension if necessary or replace the belt if worn. For internal transmission problems, professional service may be required as these repairs typically involve specialized tools and expertise.

Unusual Transmission Noises

Strange noises from your RT65 transmission often signal developing problems:

Grinding sounds may indicate gear damage
Whining noises often relate to low fluid or bearing issues
Clunking or knocking can suggest loose components

Regular transmission maintenance, including fluid changes every 100 operating hours, can prevent many transmission issues with the Cub Cadet RT65. Using the manufacturer-recommended transmission fluid is critical for maintaining proper operation.

Tine Performance Issues

The tines are the business end of your RT65 tiller, and when they don’t function properly, the machine becomes essentially useless. Several problems can affect tine performance.

Tines Not Rotating

If your engine runs but the tines don’t rotate, check these common trouble spots:

Drive belt condition: A worn or broken belt won’t transfer power from the engine to the transmission
Shear pins: These are designed to break when tines hit hard objects, preventing more serious damage
Tine shaft issues: Bent shafts or damaged bearings can prevent rotation
Clutch engagement: Improper adjustment prevents power transfer

Inspect these components carefully, replacing any damaged parts. Shear pins are an intentional weak point designed to break instead of causing transmission damage when tines hit rocks or roots, so keep spares on hand.

Uneven Tilling Performance

Uneven soil preparation can result from:

Bent or damaged tines
Improper tine assembly
Uneven ground pressure
Depth regulator improperly set

Examine each tine for damage or misalignment. They should be evenly spaced and properly secured to the shaft. The Cub Cadet RT65 tiller transmission problems can also manifest as uneven performance if the transmission isn’t delivering consistent power.

Excessive Vibration

If your RT65 vibrates excessively during operation, it could indicate:

Bent tines
Tine shaft misalignment
Loose mounting bolts
Engine mounting issues

Excessive vibration not only affects performance but can also lead to premature wear of components and operator fatigue. Address vibration issues promptly by inspecting and replacing damaged tines, checking shaft alignment, and ensuring all mounting hardware is tight.

The engine is the heart of your Cub Cadet RT65, and problems here can affect every aspect of operation.

Power Loss During Operation

Many users report their RT65 losing power during use, especially under load. This frustrating problem can stem from:

Clogged air filter restricting airflow
Dirty fuel filter limiting fuel supply
Carburetor issues affecting fuel-air mixture
Exhaust blockage creating back pressure
Ignition system problems

Regular maintenance prevents most power loss issues. Replace air and fuel filters according to the maintenance schedule, and ensure the cooling fins are clean to prevent overheating. If power loss persists after basic maintenance, a more thorough inspection of the carburetor and ignition system may be necessary.

Excessive Smoke

Smoke from your RT65’s exhaust can indicate several problems:

Black smoke: Usually indicates a too-rich fuel mixture from carburetor issues
Blue smoke: Typically signals oil burning due to worn piston rings or valve seals
White smoke: Often shows water in the combustion chamber or condensation

For carburetor-related smoke, adjusting the air-fuel mixture can often resolve the issue. Oil burning problems generally require engine repairs that might be beyond basic DIY maintenance.

Engine Overheating

Overheating can cause significant damage if not addressed promptly. Common causes include:

Insufficient engine oil
Blocked cooling fins
Operating in extremely hot conditions
Running at high load for extended periods

Maintain proper oil levels, clean cooling fins regularly, and give your machine brief cool-down periods during extended operation. These simple steps can prevent costly overheating damage. For persistent overheating issues, consult the Cub Cadet troubleshooting problems resource for more detailed guidance.

Fuel System Failures

Fuel system issues are among the most common problems affecting the Cub Cadet RT65’s performance and reliability.

Fuel Leaks

Fuel leaks are both wasteful and dangerous. They commonly occur at:

Carburetor float bowl gaskets
Fuel line connections
Fuel tank seams or caps
Fuel filter connections

Inspect your tiller regularly for signs of fuel leakage, especially if you notice the smell of gasoline during or after operation. Replace damaged fuel lines and tighten loose connections. For carburetor leaks, replacing the gaskets usually solves the problem.

Poor Fuel Economy

If your RT65 seems to consume more fuel than it should, consider these potential causes:

Carburetor running too rich
Air filter restrictions
Ignition timing issues
Operating with choke partially engaged

A properly tuned carburetor is essential for good fuel economy. If fuel consumption has increased gradually over time, a carburetor adjustment or cleaning may be necessary. Ensure the choke fully disengages when the engine warms up, as running with the choke on increases fuel consumption dramatically.

Fuel Contamination

Contaminated fuel can cause numerous problems, from difficult starting to engine damage. Common contaminants include:

Water from condensation
Dirt or debris entering during refueling
Algae growth in ethanol-blended fuels
Rust from metal fuel containers

To prevent contamination, always use fresh fuel, preferably without ethanol. Store your tiller with a full tank if it will sit for extended periods, as this reduces condensation formation. Using a fuel stabilizer is highly recommended for machines that aren’t used regularly.

Electrical System Issues

Though less complex than modern equipment, the Cub Cadet RT65 still relies on several electrical components that can develop problems.

Ignition System Failures

Ignition problems often manifest as starting difficulties or rough running:

Faulty spark plug
Damaged ignition coil
Broken kill switch
Loose or corroded wiring connections

Testing for spark is relatively simple with a spark tester tool. If no spark is present, methodically check each component of the ignition system. Many electrical problems stem from corroded connections, so cleaning terminals and ensuring tight connections can resolve numerous issues.

Safety Switch Malfunctions

The RT65 includes safety switches that prevent operation in potentially dangerous situations. When these malfunction, they can prevent starting or cause shutdowns:

Check for debris around safety switches
Inspect wiring for damage or disconnection
Test switch continuity with a multimeter
Replace faulty switches as needed

While it might be tempting to bypass safety switches when they cause problems, this creates significant safety hazards and should be avoided. Proper repair ensures both functionality and safety.

Maintenance Tips to Prevent Common RT65 Problems

Preventive maintenance is far less costly than repairs and keeps your RT65 running reliably. Implementing these practices can help avoid many of the problems discussed in this article.

Regular Service Schedule

Establish and follow a regular maintenance schedule:

Every use:
- Check oil level
- Inspect air filter
- Examine tines for damage
- Check all fluid levels
Every 25 hours:
- Change engine oil
- Clean air filter
- Check belt tension
- Lubricate moving parts
Every 50 hours:
- Replace air filter
- Check spark plug
- Inspect fuel filter
- Examine transmission fluid
Annually:
- Replace spark plug
- Replace fuel filter
- Change transmission fluid
- Check valve clearance

Following this schedule can dramatically extend the life of your Cub Cadet RT65 and prevent many common problems. For more detailed maintenance information, the Cub Cadet RT65 review page offers valuable insights from experienced users.

Proper Storage Procedures

How you store your RT65 between uses significantly impacts its longevity:

Clean the tiller thoroughly, removing all soil and debris
Apply lubricant to exposed metal parts to prevent rust
Either drain fuel completely or add stabilizer to a full tank
Store in a dry, covered location
Consider covering with a breathable cover

For seasonal storage, additional steps are recommended:

Change the oil before storage
Remove the spark plug and add a small amount of oil to the cylinder
Pull the starter cord slowly to distribute oil
Reinstall the spark plug but leave the wire disconnected
Loosen belts to prevent stretching during storage

Fuel Management Best Practices

Proper fuel management prevents many common problems:

Use fresh fuel (less than 30 days old)
Consider non-ethanol fuel when available
Add fuel stabilizer when the machine will sit for extended periods
Keep the fuel tank clean and free of debris
Use a funnel with a filter when refueling

These simple practices can prevent carburetor issues, starting problems, and fuel system damage.

When to Seek Professional Help

While many RT65 problems can be addressed through DIY maintenance, some situations warrant professional assistance.

Signs That Indicate Professional Service Is Needed

Consider professional service when:

Internal engine noise such as knocking or rattling occurs
Transmission makes grinding sounds
Engine compression is low
Major oil or fuel leaks develop
Electrical system problems persist after basic troubleshooting
Machine has been submerged or severely damaged

Professional technicians have the specialized tools and expertise to address complex issues safely and effectively. Attempting major repairs without proper knowledge can result in additional damage or safety hazards.

Cost Considerations for Repairs vs. Replacement

When facing significant repair needs, consider:

Age of your RT65
Availability of replacement parts
Cost of repairs versus replacement value
Frequency of use
Improvements in newer models

For older tillers with multiple issues, replacement might be more economical than extensive repairs. However, a well-maintained RT65 can provide decades of service, often making quality repairs a worthwhile investment. Cub Cadet transmission problems resources can help you estimate potential repair costs for transmission-related issues.

Upgrades and Modifications for the Cub Cadet RT65

Some owners choose to modify their RT65 tillers to improve performance or address recurring issues.

Performance Enhancements

Popular upgrades include:

Higher quality air filters for better engine protection
Premium spark plugs for improved ignition
Enhanced tines for better soil penetration
Improved wheels for better traction
Handle modifications for better ergonomics

While these modifications can improve performance, they should be approached cautiously to avoid compromising the machine’s reliability or safety.

Aftermarket Parts Considerations

When choosing aftermarket parts:

Research compatibility thoroughly
Consider quality versus cost savings
Read reviews from other RT65 owners
Understand how modifications might affect warranty (for newer machines)
Keep original parts for potential reversion

Quality aftermarket parts can sometimes outperform original equipment, but poorly made substitutes can create new problems. For critical components like belts and transmission parts, genuine Cub Cadet replacements often provide the best long-term value.

Frequently Asked Questions

Why won’t my Cub Cadet RT65 tiller start?

Starting problems typically stem from fuel issues, spark plug problems, or carburetor clogs. Check for fresh fuel, a clean spark plug with proper gap, and ensure the carburetor isn’t gummed up with old fuel deposits. Also verify that safety switches are properly engaged and the ignition system is functioning correctly.

What causes transmission problems in the RT65?

Transmission issues usually result from inadequate lubrication, worn belts, damaged gears, or improper adjustments. Regular fluid changes and belt inspections can prevent most transmission problems. For internal transmission issues, professional service is often required due to the complexity of these components.

How do I fix tines that won’t rotate on my RT65?

First check for broken shear pins, which are designed to break when tines hit obstacles. Also inspect the drive belt condition and tension, clutch engagement, and transmission function. Replacing shear pins is a simple fix, while belt or transmission issues might require more involved repairs.

What is the price of the Cub Cadet RT65 power weeder?

New Cub Cadet RT65 tillers typically range from $1,200-$1,500 depending on the retailer and any current promotions. Used models in good condition generally sell for $600-$900, though prices vary based on age, condition, and included accessories.

Why does my Cub Cadet start then shut off?

This behavior often indicates fuel delivery problems, carburetor issues, or faulty safety switches. A clogged fuel cap vent, dirty carburetor, or failing ignition module can also cause this symptom. Systematic troubleshooting of the fuel and electrical systems usually identifies the specific cause.

How often should I change the oil in my RT65?

Cub Cadet recommends changing the oil every 25 operating hours or at least once per season. For machines used in dusty conditions or under heavy loads, more frequent oil changes (every 15-20 hours) can extend engine life and improve performance.

What type of fuel should I use in my Cub Cadet RT65?

Use clean, fresh unleaded gasoline with an octane rating of 87 or higher. Fuel containing up to 10% ethanol is acceptable, though non-ethanol fuel is preferable for longer storage periods. Always use fuel stabilizer when storing the machine with fuel in the tank for more than 30 days.

Final Words

The Cub Cadet RT65 is a capable and durable tiller that can provide years of reliable service when properly maintained. By understanding common problems and implementing regular maintenance practices, most issues can be prevented or addressed before they become serious. Whether you’re dealing with starting difficulties, transmission problems, or tine issues, the troubleshooting approaches outlined in this guide should help you diagnose and resolve most concerns.

Remember that preventive maintenance is always less expensive and time-consuming than repairs. Establishing a regular service schedule and following proper storage procedures will significantly extend the life of your RT65 tiller. For issues beyond your comfort level or expertise, don’t hesitate to consult a qualified service technician to ensure safe and effective repairs.

With proper care, your Cub Cadet RT65 can continue to be a valuable tool for your gardening and landscaping needs for many years to come.