Brand: ROPER Model Number: RTW4516FW1 Main Symptom: agitating motion back and forth is very weak. I took apart the agitator but dogs are fine and engaging. Replaced the flat ring inside the agitator but that changed nothing. I also replaced the suspension springs, but that wasn’t it. Should I start thinking the motor or transmission are at fault? The washing cycle completes all the way without any errors or hiccups, but the agitation motion is so weak that it doesn’t wash any dirt out of the clothes.
What happens & when:
Error Code (if any): None
Parts or tests already tried: Dogs, springs
Photos / video link: https://tinyurl.com/4ha89sw8
Yes. On the Roper RTW4516FW1, since the agitator dogs are engaging and the washer completes the cycle normally, I would move the diagnosis under the washer. I would not replace the motor or transmission yet.
Unplug the washer and carefully lean it back against the wall. Remove the plastic belt/pulley shield underneath.
Inspect the belt for:
Shiny/glazed inner surface
Cracks
Rubber dust around the pulleys
Oil contamination
Excessive looseness
Evidence that it has been slipping
The belt is WPW10006384. A worn belt can still turn everything with no load but slip when the agitator has clothes pushing against it.
Quick test: With the washer unplugged, hold the large transmission pulley and inspect how firmly the belt grips it. If the belt is badly glazed or loose, I’d replace it before condemning anything expensive.
2. Inspect the splutch/clutch
This is actually higher on my suspect list than the transmission or motor.
Remove the belt and inspect the large plastic pulley/cam assembly. The splutch is W10721967.
Look closely for:
Rounded/worn plastic teeth
Cracked cam
Worn pulley
Plastic shavings
Weak/broken spring
Parts not fully engaging
Cam hanging partially between positions
Have someone move the actuator mechanism by hand while you watch how the cam engages.
A splutch that only partially engages can give you exactly what you’re describing: the washer agitates, but the stroke has very little authority behind it.
3. Check the gearcase manually
With the belt removed, turn the large gearcase pulley by hand.
It should turn smoothly with consistent resistance.
Then rock it back and forth.
You’re looking/feeling for:
Excessive free play before the agitator responds
Grinding
Clicking
Binding
Large amounts of backlash
Gearcase shaft moving excessively up/down
Oil leaking from the gearcase
Pay particular attention to how much you can move the pulley back and forth before the agitator actually moves.
A little gear lash is normal. If you’re getting a significant amount of pulley movement before the agitator responds, I’d start suspecting worn internal gears in the gearcase/transmission.
4. Compare the motor to the gearcase
Leave the belt off and rotate the motor pulley by hand.
It should rotate smoothly without rough spots or excessive shaft play.
I put the motor fairly low on the suspect list in this situation. If the motor were weak enough to barely agitate a load, I would normally expect other symptoms such as difficulty starting, humming, overheating, stopping, or spin problems.
Also inspect the motor run capacitor and connections while you’re underneath. The original parts listing shows a separate motor run capacitor on this machine.
A very useful loaded test
Before buying anything, I’d do this:
Run the washer with a small load and let it enter wash/agitation.
Watch the lower half of the agitator, not just the upper auger.
If the lower agitator is making a full, strong back-and-forth stroke but the upper auger isn’t, go back into the agitator.
If the entire agitator has a short/weak stroke, you’re looking below the agitator — belt, splutch, actuator, or gearcase.
If you hear the motor working normally but see the large pulley/belt slipping or hesitating, you’ve essentially found the problem.
The suspension rods you replaced wouldn’t normally cause weak agitation. They control tub movement during operation rather than transferring motor torque to the agitator.
I would definitely inspect the W10721967 splutch and WPW10006384 belt before spending money on a transmission. They’re accessible from underneath and both are known parts of the agitation drive system on this exact model.
If the belt and splutch look good, the next thing I’d do is run the washer’s diagnostic/service mode and command the low-speed agitation test. That can help separate a mechanical gearcase problem from an actuator/motor-control problem.