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Honda Harmony 215 Transmission Problems

Eddie spent 35 years in the automotive business with Honda. He is an ASE Certified Master Technician and has bruised knuckles to prove it.

Let’s face it: the Honda Harmony 215 is a great lawn mower. It’s self-propelled, it has more power than your standard mower, and it mulches great with a killer mulching blade. But, it seems like everyone is looking for information on how to fix its transmission. I watched videos, read all kinds of forums, and checked out Yahoo Answers, but nothing seemed to answer my question, “How do I fix my Honda Harmony transmission?”

When I couldn't find a good answer to this question, I decided to take matters into my own hands and fix my transmission problem myself. Now I am passing on this valuable information, along with two other transmission issues other do-it-yourself mechanics have identified, and a bonus carburetor cleaning process. Please leave a comment if you have any questions; maybe I can help.

Transmission Problem #1: Drift Key on Axle Shaft

I was reluctant to remove the transmission because it is buried inside the lawnmower. But because I really wanted my self-propulsion back, I sucked it up and dug in. It really wasn’t too bad once I got the lower cover off under the mower deck; that gave me a really good view of the transmission. But in fact there is no need to go this far, if you have the problem I did. In my case, the problem was the drift key on the drive gear.

Replacing the transmission would have been one way to fix my problem, because along with the transmission I would have replaced the part that was giving me the problem. The new transmission comes with a new axle shaft, and the axle shaft is where the problem exists.

The Drift Key Was the Problem

This drift key is what causes the ratcheting noise when you pull the lawn mower backwards. The key is spring-loaded, and the spring is part of the shaft. This spring needs to move freely in and out of the axle shaft. If the key is sticking in the shaft, the rear wheels will not engage completely, and will cause a jerking or a stutter when trying to engage the transmission.

Honda Harmony 215 Drive System

Drive Gear

Drive Gear

Notice where the drift key would seat

Notice where the drift key would seat

Gear, drift key, snap ring and washer set

Gear, drift key, snap ring and washer set

Rear wheel with metal gear

Rear wheel with metal gear

Axle shaft with drift key slot. The spring is located inside the axle shaft.

Axle shaft with drift key slot. The spring is located inside the axle shaft.

Remove the Rear Wheels

If you’re anything like me, you probably have had the rear wheels off your Honda Harmony 215 many times, and you probably have had the small drive gear off as well. There is a small drift key between the drive gear and the shaft. The drive gear is directional, which means it needs to go on the shaft a certain way. If you reinstall it in the wrong direction, it won’t drive the wheel.

Care of the Axle Shaft

Clean any debris and dirt off the shaft and make sure there are no burrs on the axle shaft. If there are, lightly file them down. Grease the shaft and the key so all parts move freely.

Proper Installation of the Drive Gear is a Must

Reinstall the drive gear in the proper direction and reinstall the snap ring. When you turn the drive gear clockwise, it should move freely, and you should hear the ratcheting noise. When you turn it counterclockwise, the drive gear should grab the drift key and rotate the axle shaft. Reinstall the wheels and give her a test run. See my video below.

Adjusting the Transmission Shift Cable

One other adjustment I needed to make was the transmission shift cable (this is different from the cable to engage the wheels). The linkage on the transmission seemed to have gotten a little sloppy after 14 years of use, and the cable was not engaging the transmission completely. Just play around with the adjustment on the shift cable so that it will engage the transmission completely.


Read More from AxleAddict

Drive Gear Needs to Be Installed Properly

A Peek Inside the Honda Harmony Transmission

honda-harmony-215-transmission-problems

This is just a quick note for the curious folks. When I went further and opened the transmission on my Honda Harmony 215—here's an article with pictures, and here's a video—I was very surprised at what I saw. I was expecting to find plastic gears all chewed up and worn out. But all the gears are hardened steel; this transmission is bulletproof, although the linkage can get pretty sloppy. Someone would have to thoroughly abuse the mower to kill this transmission. I make my lawnmower work hard, but after 14 years of use, the transmission looked like new inside, except for the old grease. I own a lot of Honda machines, and taking this lawnmower apart proved to me once again that Honda makes a great product.

The Transmission Problem Paul Found on His Honda Harmony Mower

Who is Paul?

Paul and I have been going back and forth with the issues with his Honda Harmony 215 SD mower, as you can read in the comments below. Paul's Honda mower is not the exact same model as mine, but he found a different problem and made some awesome funny videos to help anyone who may have the same problem; they are above and below this paragraph.

Thanks, Paul, for all the feedback and the videos, it was a pleasure helping you get through this tough repair.

If anyone else has a problem with their Honda Harmony mower and they know how to fix it, make a video and I will post it right here just like I did with Paul's videos. The videos have to be about the Honda Harmony mower and no other brand. I'll see you in the comment box at the end of this article.

Paul's Honda Harmony Fix Video #2

Donald's Honda Harmony

1994 Honda Harmony Mower Model # HRM215K1SDA

1994 Honda Harmony Mower Model # HRM215K1SDA

1994 Honda Harmony Mower Transmission Issue, Model # HRM215K1SDA, by Donald

Donald is a wild and crazy guy who loves to tear apart anything that will challenge his abilities. He came to me for advice about his Honda Harmony transmission and ended up teaching me a thing or two. He said his Honda Harmony transmission would walk along the axle shaft until it hit the grass chute. It took me a while to understand what he was talking about, and eventually he sent me a video explaining it with great detail, using a hammer and a transmission! See the video below and you will understand what I mean.

He ended up tearing apart the transmission, only to find our transmissions were not alike internally or externally. He did find a broken c-clip inside the transmission that was causing his problem. The c-clip was what held the bearing race in place on the shaft; because the c-clip was being broken, the transmission would walk down the shaft, and eventually hit the grass chute and stop. Below I added some pictures from Donald's transmission; he kindly shared them for the world to see. Keep in mind that this mower sat outside for most, if not all, of its life; it's a crying shame for such a beautiful mower!

Donald's Honda Harmony Transmission Issue

Inside the Honda Harmony Transmission #HRM2151KSDA

Levers, clips and seals

Levers, clips and seals

Internal parts

Internal parts

Gears and shaft

Gears and shaft

Broken c-clip or snap ring

Broken c-clip or snap ring

honda-harmony-215-transmission-problems
Grease in transmission mixed with water, from the mower sitting outside its whole life

Grease in transmission mixed with water, from the mower sitting outside its whole life

honda-harmony-215-transmission-problems
honda-harmony-215-transmission-problems
honda-harmony-215-transmission-problems
honda-harmony-215-transmission-problems

Cleaning a Honda Harmony Carburetor

Donald shared a great tip for all you DIY guys and gals: instead of cleaning the carb with toxic chemicals like carb cleaner, Donald likes to boil the carburetor in lemon juice, yes I said lemon juice, and it smells much better then carb cleaner. Take a look at the pictures below: the carburetor looks brand new, even the float looks super clean!

The last time I talked to Donald, he said he was making a video about this 1994 Honda Harmony HRM215K1SDA, so check back often to see if he or other readers have added even more information to this Honda Harmony page. The more we learn, the longer we can keep these bad-ass machines alive!

Using Lemon Juice to Clean a Carburetor

Rusted carburetor

Rusted carburetor

Carburetor after boiling in lemon juice

Carburetor after boiling in lemon juice

How to Remove a Stud from a Lawn Mower Carburetor

Lawn Mower Carburetor Cleaning Tips

Honda... What Will They Think of Next?

This article is accurate and true to the best of the author’s knowledge. Content is for informational or entertainment purposes only and does not substitute for personal counsel or professional advice in business, financial, legal, or technical matters.

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