Lawn Mower Hard To Push

Pushing a heavy mower isn’t fun, especially on a hilly yard. Most of my garden is hilly, there’s no way I could push it without the drive system.

So why is your lawn mower hard to push? The most likely reason a mower is hard to push, is because the drive cable needs adjustment. Other possible causes include:

  • Worn drive belt
  • Damaged pulley
  • Damaged¬†trans-axle
  • Worn wheels

In this post I’ll show you how to adjust your own drive cable for free. This is an easy job and is most likely the cause of a hard to push mower. But I’ll also cover a few other possibilities.

If you need video help, check out my mower repair video library, it walks you through the diagnosing and repair of common mower self drive problems.

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Mower on a hill

Poor cable tension

Below you'll find a short outline of the main components of a lawn mower drive system and what they actually do.

How a mower drive system works

Mowers are as you know pretty simple bits of kit, the engine powers the cutting blade as it’s directly connected to the engine crankshaft, but how does the engine power get to the wheels?

Your mowers drive system comprises of four main components.

  1. The drive crankshaft pulley
  2. A drive belt
  3. The rear axle assembly
  4. Drive cable
Mower trans-axle Mower engine dipstick

Drive system

Four components make your mower move:

  1. Crank pulley
  2. Drive belt
  3. Trans-axle assembly (incl. wheels)
  4. Drive cable

1 Crankshaft pulley

The crankshaft pulley is dedicated to sending power to the trans-axle. It’s fitted right under your mower engine, fixed to the crankshaft, so when the engine is running the drive pulley is working.

Pulley’s usually have a plastic or metal shroud to help protect them from flying debris. Often the shroud comes loose, which allows grit and stones hit the pulley causing damage.

Your pulley may or may not be visible when you turn your mower over. (always turn your mower over with carburetor side facing up – prevents gas spill and flooding)

Mower drive pulley

Crank pulley

Crank pulleys become brittle over time and a direct hit can cause them to break.

This mower has lost its protective shroud.

2 Drive Belt

A drive belt is as its name suggests a belt that transfers engine power from the crankshaft pulley to the trans-axle. The drive belt is very similar in design to an automotive alternator belt.

They are very often the cause of lots of mower drive problems. Symptoms vary, but a hard to push mower is high on the list. Other symptoms include:

  • Squealing noise
  • Slow moving
  • Slow to start moving
  • Binding
  • Vibration
  • Intermittently slow
  • Hard to push
  • Stops when hot

Drive belts are like car tires, are expected to wear out and should be inspected at the beginning of each season. Belts will usually let you know what’s going on though, you may see cracking, peeling or flat spots.¬†

A mower drive belt should be changed every third or fourth year depending on work load. 

Mower drive belt repair

Drive Belts

The right belt is mission critical, getting this wrong can cause even more problems.

The missing shroud on this mower will cause debris to impact the belt and will shorten its life.

3 Trans-axle

Trans……what? Is that even a real word? Mmm, I think so. A trans-axle is the name given to the complete assembly. That’s the transmission, differential and the axle combined into one compact unit.

If you want to read more about lawn mower trans-axles, you can check out this post “What’s a lawnmower trans-axle?”

The trans-axle is the business end of making your mower actually move. It has a pulley fixed to the top of the assembly to receive the drive belt. These pulley’s are pretty durable but on some axles are made of plastic, you can guess what happens to them over time.

Anyway the transmission component of the trans-axles unfortunately does usually wear out before the engine. Especially mowers that spent their working life laboring on a hilly yard.

And the worse news is mower manufacturers don’t usually supply internal parts for the transmissions. However they will sell complete transmissions. For some mowers paying for a new tranny and the labor to fit may not make economic sense.

Other common trans-axle problems include axle-pins and wheel drive gears, these guy’s simply wear out, and again may not be economically viable to repair.

Lawn mower transmission Lawn mower on its side.

Trans-axle

Trans-axle or transmission, both words are used to describe this component. But trans-axles is a more accurate description of this type transmission.

A lawn mower trans-axle may be fitted to the front or the rear of the mower, making the mower either front or rear wheel drive.

Trans-axles are commonly lubricated at factory for life.

Lawn mower drive gear Lawn mower drive gear pin Lawn mower drive gear

Other common axle issues

Worn drive gears on axle and wheels. Worn axle pins which cause a lack of drive.

4 Drive Cable

A good drive system requires control, you need the ability to progressively apply power. This is usually done by way of control lever and braided cable. Same type cable used on bicycle brakes.

The cable pulls on a lever mounted on the transmission. The lever locks the transmission progressively, which causes the mower wheels to move.

As you can imagine, any thing that prevents this lever from being fully applied will cause the mower to feel slow. This is the most common cause of a slow transmission and can fixed in a snap.

Tractor mower seal

Transmission lever

The cable is connected to a lever on the transmission. This lever must be fully engaged in order to have full drive power.

Adjusting the drive system

And finally adjusting the drive system. This isn’t a difficult process, but there’s a few tips you’ll need in order to get it right. It covered in the pictures below.

Your mower drive adjuster may not be identical to the one’s shown here, but that’s OK, because the principle is the same.

Some mowers will have a tool-less adjuster, nice!, makes life a ton easier. However most mowers will require tools, but not many, two vice grips or adjustable wrenches is all you need.

If you’ve got some WD40, shoot it down the cable inner, you might need some eye protection, tends to splash back, Awkward? Yes, but worth the effort.

Mower drive control lever Mower drive cable

Locate the cable

Locate the correct cable by operating the handle bar drive control lever.
Mower drive cable adjuster Mower drive cable adjuster

Drive adjuster

Now go ahead and locate the cable adjuster.

Two types are common:

  1. An adjuster at the drive control lever bracket
  2. In line cable adjuster

Both types will have a lock nut, it prevents the adjuster from backing out.

Simply open the lock nut by holding one nut and opening the other. Back off the lock nut so as to allow plenty of room for adjustment.

Mower drive adjust Mower drive cable Mower drive cable

Take up slack

Adjustment is easy, our goal is to adjust the cable so that it moves further away from the drive control lever.

Run it out a few turns, but don't tighten up the lock-nut just yet.

Mower drive control lever

Free

This is an important step, if you over adjust the cable, you'll find the mower difficult (stiff) to reverse. If you have over-adjusted, not a problem, just back it off a few turns.

I like to over adjust and then back it off until I find the sweet spot, then I know I have reached max adjustment - make sense?

Mower drive cable lock-nut

Tighten locknut

When your happy, tighten the lock-nut and your good to mow, Your welcome!

Related Questions

Self propelled lawn mower hard to push? The most common cause of a hard to push self propelled lawn mower is poor drive cable adjustment.

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Auto Technician and Writer at | Website

John Cunningham is an Automotive Technician and writer on Lawnmowerfixed.com. I've been a mechanic for over twenty years, I use my knowledge and experience to write "How to" articles that help fellow gear-heads with all aspects of mechanical repairs, from lawn mowers to classic cars.