Honda Lawn Mower won't Start

Honda Lawn Mower won't Start

Your Problem Will Likely Be Loose Battery Connections, Flat/Faulty Battery Or Faulty Starter Solenoid.

Causes

01. Fuel Valve Off

02. Choke Not On

03. Bad Gas

04. Plug Wet/Faulty

05. Plug Wire Off

06. Air Filter Blocked

07. Carburetor Fault

08. Coil Fault

09. Bail Lever/Ignition Fault

10. Flywheel Timing (Shear-key)

11. Sticking Valves

12. Low Compression

Most Common Cause

The most common reason a Honda mower won't start - Gummed up carburetor. 

 

Honda make reliable, well designed and constructed mowers. You bought one, so you already know this.

 

I work on lots of Hondas and major failures are very rare. Let's begin by doing some basic checks. Sometimes this will solve the problem or at least point you in the right direction.

 

This guide will assume that components such as pull cord, throttle levers etc are working OK. If you think that this is not the case, I wrote a guide that covers all pull cord common problems - check out "Pull cord troubleshooting".

 

 

Check the Basics

Is the oil level low? 

Is the gas turned on?

Is the gas fresh? 

Is the choke on and working? 

Is the air filter clear and dry?

Is the plug wire on securely?

Is the bail lever on and working? 

 

That's all the easy stuff checked, now we'll dig a bit deeper.

 

Oil Level

Some Honda mowers won't start if the oil level is low, this isn't a flaw, it's designed that way to protect the engine. It's good practice to check the oil level every time you fill the gas tank. Check on level ground and with all wheels set to the same height.

 

The Honda will take .58 of a quart (.55lt) from empty. If your in any doubt about how to check the oil, you'll find this guide helpful - "How to check lawn mower oil".

 

 

A Honda won't like to be over filled with oil either, this can damage the engine, cause it to smoke,leak oil and sometimes not start.

 

 

 

Mower Oil Level check

Check Oil

Check Oil


mower oil check

Gas Level

Is there gas in the mower? Sometimes the obvious is the solution, and as Sherlock Holmes says "we should check a fact is indeed a fact". The customer may have filled the gas tank with what they thought was good gas.

 

At my shop I have found many strange concoctions - diesel, water, white spirits, vinegar and of course last years gas makes a regular appearance in the tank. 

 

The fix for bad gas - drain the tank and clean the carburetor. You might find this guide helpful, it walks you through the whole process - "Carburetor clean out".

 

Fresh Gas


Mower gas tank

Remove air filter cover and air filter, some will be fixed on with screws or wing nuts, others will just pull off.

Mower gas tank

Fresh Gas

Gas Tap On

The fuel tap is used to cut fuel supply to the carburetor. I tell my customers to turn off the fuel when the mower isn't in use. It's easy to forget to turn it on. Honda fit their fuel tap on the right hand side of the engine when viewed from the front of mower. 

 

This short guide with pictures shows you where your gas tap is, what it's for and when to use it. Check out "Where is my lawn mower gas tap".

 

Gas Tap On


Mower gas tank

Remove air filter cover and air filter, some will be fixed on with screws or wing nuts, others will just pull off.

Honda mower gas tap

Gas On

Air Filter

A blocked air filter will prevent the mower from starting. The Honda air filter needs to be kept clean, check it every 25 hours of use, and replace every 100 hours. Honda fit tool less air filter covers, makes cleaning super easy.

 

The air filter cover is on the right hand side of the engine, opposite the muffler. Cleaning the filter with compressed air would be nice, but banging on the ground will do just fine. 

 

This guide will help you service your mower in under an hour - "Mower tune-up".

 

mower air filter

Clean

Air Filter Clean


Mower throttle lever

If you have a manual choke control, move throttle lever to full choke position to start a cold engine. 

Remove the air filter, this allows you view the choke plate, seen here in the choke fully on position.

The plate should be fully closed, if not check cable adjustment.

Plug Wire On

It's easy for the plug wire to come loose, happens all the time. The plug wire lives right at the front of the engine, so it's banging into shrubs and hedges and the like. It's the black wire with the rubber boot on the end. Just make sure it's making good clean contact with the plug. Bad or no contact will give you a no start.

 

 

 

 

Plug Wire On


Honda plug wire
Carburetor primer

Wire On

Choke On

I meet lots of customers who don't know how to use the choke correctly, and I don't blame them, likely they weren't shown by the retailer. The choke is used to start a cold engine. A cold engine needs more fuel than a hot engine, so the choke creates a richer air fuel ratio.

 

Some Honda's will have the traditional choke lever and more modern mowers will have the auto choke set up.

 

Not sure if your choke is working? This guide will walk you through the testing procedure, it's simple and includes pictures - "Choke testing".

 

If your mower doesn't start on the 3rd attempt it's very likely that the plug is now saturated in fuel - condition known as flooded. The fix is to remove and dry the plug or leave the mower for 30 minutes to dry out, and then try again, this time without choke. 

 

If your in any doubt about how to start a mower, this guide covers it all, you'll be a pro 2 minutes from now - "How to start a lawn mower".

 

 

Choke On


Mower plug wire

Some Honda mowers are fitted with auto choke and so the choke won't be controled by the lever.

Choke On

Some Honda mowers are fitted with auto choke and so the choke won't be controled by the lever.


Honda mower throttle

Bail Lever On

The Bail lever or dead mans lever, is a safety feature. Its function is to stop the spinning blade within 3 seconds of release. It does this by shutting the engine off and applying a flywheel brake. If the bail lever isn't held the mower won't start.

 

This guide will walk you through testing for spark and how to change a coil, it's simple - "Ignition system testing".

 

 

 

 

Honda mower bail lever

Bail On

Only some Honda mowers will have the stop/start controled by the bail lever.

Other Hondas have the stop/start control built into the throttle lever.

Bail Lever On


Mower tune-up kit

Only some Honda mowers will have the start/stop controled by the bail lever. Other Hondas have the start/stop control built into the throttle lever.

Bad Gas

Bad gas is the number one cause of no starts. Your gas could be clean but stale, and mowers don't like stale gas.

 

Gas starts to go off after one month, it losses its ability to combust which causes poor performance and misfiring. When it goes completely stale, usually around 3 months old, it starts to solidify.

 

When storing your mower for longer periods, the stale gas can gum up the fuel system. Gumming can avoided by using a gas stabilizer, you won't have to use it all season, just at the tail end.

 

It's simple to use, just dump one ounce of gas stabilizer into 2.5 gallons of gas, fill your gas tank and run the engine to mix it throughout the fuel system, that's it. This stuff will protect and clean your fuel system and can be used in all gas powered kit including 2 stroke engines.

 

I use a brand called Sta-bil gas and you can check it out on Amazon.

 

 

 

 

 

 

Gumming

It's a carburetor killer, using a gas stabilizer will prevent a lot of problems.


Mower carb Mower carb

Gumming


Mower carburetor gumming Mower gas stabilizer

Remove plug wire and turn off fuel as before. Loosen bolt on the fuel bowl. Remove the air filter clean or replace before refitting.

Gas Shot

Your engine needs fuel, spark and compression to start. Fuel, Spark and Compression are broader areas than their title suggests. Testing will take into account the complete system, for example fueling is more than just the gas, it includes carburetor, tank, air and fuel filters, gas line, intake manifold, etc.

 

The most likely cause of a no start Honda is fueling, and so we will start there. Next most likely is spark and least likely of all is a compression issue. 

 

To quickly test for a gas issue - by pass the fuel system. We do this by pouring some fresh gas directly into the carburetor.

 

The symptoms of bad gas vary: mower won't start; mower runs rough; runs but only with choke; splutters when cutting on a slope; dies when cutting grass; lawn mower starts and then dies.

 

 

 

Remove


Honda mower air filter

Remove the air filter, by pressing the two plastic tabs.

Gas


Honda mower air filter

Tilt your mower over and pour a cap full of gas into the carburetor.

Pull


Honda mower start Honda mower smoking

Attempt to start the mower in the normal way.

There are two possible outcomes -

(1) Mower attempted to start or started - tells us we have a fueling fault.  Check out "Choke system"

(2) Mower made no attempt to start - then we've likely eliminated a fueling fault, and the fault will probably be a lack of spark. Check out "Ignition system check"

Remove

Remove the air filter, by pressing the two plastic tabs.


Honda mower air filter

Gas

Tilt your mower over and pour a cap full of gas into the carburetor.


Honda mower air filter

Pull

Attempt to start the mower in the normal way.

There are two possible outcomes -

(1) Mower attempted to start or started - tells us we have a fueling fault.  Check out "Choke system"

(2) Mower made no attempt to start - then we've likely eliminated a fueling fault, and the fault will probably be a lack of spark. Check out "Ignition system check"


Honda mower Honda mower smoking

Honda Tune-up

Your Honda engine should be serviced at least once per season, ideally in the spring. Tune-up kit includes: oil; plug; air filter; fuel filter (if fitted); new blade (optional).Your Honda engine will likely be a Gcv 160 or Gcv 190cc. The service kits will be identical, however Items such as carburetors and blades will be different. 

 

Check out "Mower tune-up guide".

 

Buying the tune-up kit on line is easy. You can find your model code right at the base of the handlebars, on the body of the mower. Honda mower engines are very common and so you won't have a problem getting a tune-up kit to match.

 

Check out "Honda parts look-up". 

 

Tune-up


Honda mower

Kit should include, oil, plug and air filter. Replacing the blade is optional.

Model Number


Honda mower engine code Honda mower smoking

Tune-up

Kit should include, oil, plug and air filter. Replacing the blade is optional.


Honda mower engine

Model Number


Honda mower engine Honda mower engine code

Choke System

Your mower won't start if the choke is faulty. In this next step we need to be sure the choke system is working correctly. The correct starting procedure for a cold engine will require giving it extra gas to enrich the fuel/air mixture which a cold engine needs for a smooth start.

 

 

Choke Testing

Honda use a choke plate type system to achieve this fuel enriched condition.Your mower won't start if the choke is faulty.

 

The manual version which will have a throttle lever to control the choke.The auto choke version won't have a choke lever. Instead, a thermostat mounted close to the muffler heats and pushes on a lever which opens the choke plate.

 

Choke On

Remove the air filter, this allows us view the choke plate.

If you have a manual choke control, move throttle lever to full choke position to start a cold engine. Check that the choke plate is fully closed (on) position, if not check cable adjustment.

Your Honda may have auto choke. If so, when cold, the choke plate should be closed, as per picture. If not, move plate by hand to see if its stuck. If sticking, try WD40.

If you found no issues with your choke system, move on to "Gas Bowl Clean".


Honda mower throttle lever Mower carb

Choke Off

When the mower has started, the throttle should be moved to the run position. Check that the choke plate is in the fully open (off) position as per picture. If not, adjust cable.

A sticking choke will run poorly and puff black smoke from the muffler. Your Honda may have auto choke. If so when hot, the choke plate should be open, as per picture. If not, replace choke thermostat at the muffler.

If you found no issues with your choke system, move on to "Gas Bowl Clean".


Honda mower throttle lever Mower carb

Choke On


Honda mower throttle lever Honda mower choke

Remove the air filter, this allows us view the choke plate.

If you have a manual choke control, move throttle lever to full choke position to start a cold engine. Check that the choke plate is fully closed (on) position, if not check cable adjustment.

Your Honda may have auto choke. If so, when cold, the choke plate should be closed, as per picture. If not, move plate by hand to see if its stuck. If sticking, try WD40.

If you found no issues with your choke system, move on to "Gas Bowl Clean".

Choke Off


Honda mower throttle lever Honda mower choke

When the mower has started, the throttle should be moved to the run position. Check that the choke plate is in the fully open (off) position as per picture. If not, adjust cable.

A sticking choke will run poorly and puff black smoke from the muffler. Your Honda may have auto choke. If so when hot, the choke plate should be open, as per picture. If not, replace choke thermostat at the muffler. 

If you found no issues with your choke system, move on to "Gas Bowl Clean".

Ethanol Gas

Honda recommends not using fuels with more than 10% ethanol. Ethanol is an alcohol fuel made from sugar, corn and other plant materials. This alcohol is then blended with gas to make ethanol. It's claimed that the alcohol content of the ethanol will damage the carburetor's rubber seals and hoses.

 

E15 contains 15% ethanol and is not OK to use in Honda mower engines. E15 burns hotter than other fuels, your mower is not designed to run at these temperatures. Ethanol absorbs moisture from the atmosphere. If the fuel is left in the mower over the winter, the moisture collects in the carburetor. The water will often corrode and leave a varnish type deposit which blocks up the ports. This is what causes the poor running/no start. 

 

Gas Stabilizer

Regular gas older than three months is stale unless you use a fuel stabilizer. Ethanol fuels are stale after one month. Gas is the number one reason for a no start or poor running.

 

Using a stabilizer will prevent lots of these problems. As you know, you don't have to use the stabilizer all season, but do use towards the end and when winterizing the mower.

 

Treating your gas will save you downtime, hauling your mower to the shop and  $$$ in repair costs.

 

 

Gas Stabilizer


Gas stabilizer

Just dump a few drops into into the gas tank, and run the engine. Simple!

Stabilizer

Just dump a few drops into into the gas tank, and run the engine. Simple!


Gas stabilizer

Gas Bowl Clean

Often just cleaning the gas bowl does the job. Removing the carburetor is a bit of a mission, so if cleaning the bowl gets us out of trouble, it's worth trying. If you suspect stale gas, then you'll need to drain the gas tank also. You can drain the tank by removing the fuel line, I use a Briggs and Stratton oil extractor, you can check the price on Amazon.

 

In other cases you'll need to remove the carburetor, clean it thoroughly and drain the gas tank. Honda mowers are fitted with different size and types of engines.These engines will be fitted with different types of carburetor. Your carburetor may look different, but the process is the same. 

 

In this part of the guide I will remove just the fuel bowl, spray in some carburetor cleaner. You can find your fuel bowl behind the air filter. You don't need to remove the air filter housing to access the bowl.

 

Remember if your gas is older than three months, it's stale. So cleaning the bowl won't always make it go. You may need to drain the tank, carburetor bowl and fill with fresh gas. If this works out for you great! 

 

If not, check out this guide it covers the whole process and includes pictures - "Carburetor clean out".

 

 

 

Pull Wire

When working on your mower remove the plug wire and turn off the gas. This prevents a spill.


Mower plug wire Honda mower gas tap

Remove

Removing the 10mm drain bolt will drain the bowl, but won't clear the grit from the bowl. I like to remove and clean the fuel bowl.

Drain the fuel tank, now if you need to.

Turn on the gas to check fuel flow, if no fuel flows from the carburetor as per picture, move on to - "Fuel flow test".

Spray some carburetor cleaner up at the main fuel jet before refitting the bowl.

That's it, test mower and if it's still not right, check out "Carburetor cleaning".


Mower plug wire Honda mower gas bowl Honda mower gas bowl Honda mower gas bowl

Pull Plug wire


Gas stabilizer Gas stabilizer

When working on your mower remove the plug wire and turn off the gas. This prevents a spill.

Remove Bowl


Mower gas bowl mower gas bowl mower gas bowl mower gas bowl cleaning

Removing the 10mm drain bolt will drain the bowl, but won't clear the grit from the bowl. I like to remove and clean the fuel bowl.

Drain the fuel tank, now if you need to.

Turn on the gas to check fuel flow, if no fuel flows from the carburetor as per picture, move on to - "Fuel flow test".

Spray some carburetor cleaner up at the main fuel jet before refitting the bowl.

That's it, test mower and if it's still now right, check out "Carburetor cleaning".

Clean Carburetor

Okay, I will assume you have tried cleaning the fuel bowl as per the above guide without success. Now you need to remove the carburetor and clean it. Have some carburetor cleaner or similar, container for nuts and bolts and take lots of pictures to help you remember where levers and gaskets are positioned.

 

There are a couple of different styles of carburetor, yours may look a little different, but the process is the same. Some will have a manual choke, others will have auto choke. Some will be more challenging to remove than others. 

 

If you find carburetor corrosion or it's badly gummed up, go ahead and replace it, because nobody likes doing a job twice. Replacement carburetors are not expensive. Note that Gcv 160cc and Gcv 190cc carburetors look the same, but are different, so when ordering have your model number handy.

 

 

Strip Down

Removing a Honda carburetor can be a little challenging. It's not complex but there's lots of gaskets which must be replaced in the same order. In addition, the air filter housing bolts are also the carburetor bolts, so the challenge is to align gaskets, carburetor and air filter housing before threading the bolts.

 

Take lots of pictures of gaskets and carburetor link positions. Lay out your gaskets in an order that makes sense to you. 

 

All you really need here is patients.

 

Remove

Remove plug wire and turn off fuel as before. Loosen bolt on the fuel bowl.

Remove the air filter clean or replace before fitting.

Loosen the air filter box/carburetor bolts (3) - two carburetor bolts and one air box bolt.

Have a suitable container for small parts.

Fitted to the back of the housing is a pipe which just pulls off, it's the crankcase breather.


Honda mower air filter Honda mower air filter housing Honda mower carburetor

Air Box

Take pictures of gaskets and locations. 

Remove 3 bolts and take more pictures of throttle link locations.

Set any loose gaskets aside, and in order. 

Some will stick to the carburetor or other components and that's fine don't remove them.

Gaskets must be fitted in the same location and orientation.


Honda mower carburetor Honda mower carb

Drain Gas

If you haven't already, drain out the old gas.

Use a long flat screwdriver, prise off the gas line, removing the gas cap speeds up the draining process.

Best to do this outside, gas stinks.


Honda mower carburetor Honda mower gas line Honda mower gas drain

Links

With the fuel line removed, you can turn the carburetor on its side to  unhook the choke, throttle links and spring.

Don't be tempted to bend the links.

With the carburetor free, move to a bench.


Honda mower carburetor Honda mower gas line Honda mower gas line Honda mower gas drain

Strip Down

Move to a clean area, and remove the bowl. 

Remove the float and needle, this is done by pulling the pin.

If your bowl is very corroded, go ahead and order a new carburetor as repairing rusty carbs isn't worth the effort.

Check the needle tip, a worn tip turns pink.  When these seal tips wear, they can cause either too much fuel flow or no flow.

Replace needle or replace whole Honda carburetor.


Honda mower carburetor Honda mower gas line Honda mower gas line Honda mower gas line

Screw

Remove the main jet retaining screw. These guys are made from brass which is a soft metal.

So a proper fitting screwdriver is essential, otherwise the screw will be damaged.


Honda mower carburetor Honda mower gas line

Jet

The brass main jet seen in the top picture, needs to be pushed free.

Take a suitable screwdriver and push on the jet, to free it.

It may need further encouragement, tap on the jet housing as per picture, until jet is free.


Honda mower carburetor Honda mower carburetor Honda mower carb Honda mower carb jet

Clean

Clean the port holes of the jet and retaining screw  thoroughly. I use a strand of wire plucked from a wire brush.

The holes may look clean, but are dirty. After you have cleaned them, they will be noticeably bigger.

This allows more fuel to flow to the engine.


Honda mower carburetor jet Honda mower carburetor

Spray

Spray all carburetor ports liberally with carburetor cleaner, fuel inlet, float needle seat, jet, throttle plate, choke plate and any other ports you can see.


Honda mower carburetor jet Honda mower carburetor

Rebuild

Reassemble, fit the jet, screw, float and needle. Careful when fitting the gas bowl, the large o ring can become pinched, apply some oil to help it seat.

Don't overtighten the bowl, it causes it to leak.

Refit carburetor to the mower. Take special care when fitting the gaskets. Check your reference pictures.

This bit gets overlooked, but it's important. Clean out the fuel can and your gas tank.

Check it for grit and if you're not sure the gas is good, replace it.

Fill with gas and turn on fuel. Fit spark plug wire, and you're good to go.


Honda mower carburetor Honda mower tank Mower gas can

Remove


Honda mower air filter Honda mower air box mower gas bowl

Remove plug wire and turn off fuel as before. Loosen bolt on the fuel bowl.

Remove the air filter clean or replace before fitting.

Loosen the air filter box/carburetor bolts (3) - two carburetor bolts and one air box bolt.

Have a suitable container for small parts.

Fitted to the back of the housing is a pipe which just pulls off, it's the crankcase breather.

Airbox


Honda mower carburetor mower gas bowl

Take pictures of gaskets and locations. 

Remove 3 bolts and take more pictures of throttle link locations.

Set any loose gaskets aside, and in order. 

Some will stick to the carburetor or other components and that's fine don't remove them.

Gaskets must be fitted in the same location and orientation.

Drain Gas


Honda mower carburetor Honda mower gas line mower gas drain

If you haven't already, drain out the old gas.

Use a long flat screwdriver, prise off the gas line, removing the gas cap speeds up the draining process. Best to do this outside, gas stinks.

Links


Honda mower carburetor Honda mower gas line Honda carburetor clean mower carb

With the fuel line removed, you can turn the carburetor on its side to  unhook the choke, throttle links and spring.

Don't be tempted to bend the links.

With the carburetor free, move to a bench.

Strip Down


Honda mower carburetor Honda mower gas line Honda carburetor clean mower carb

Move to a clean area, and remove the bowl. 

Remove the float and needle, this is done by pulling the pin.

If your bowl is very corroded, go ahead and order a new carburetor as repairing rusty carbs isn't worth the effort.

Check the needle tip, a worn tip turns pink.  When these seal tips wear, they can cause either too much fuel flow or no flow.

Replace needle or replace whole Honda carburetor.

Screw


Honda mower carburetor Honda mower gas line Honda carburetor clean mower carb

Remove the main jet retaining screw. These guys are made from brass which is a soft metal.

So a proper fitting screwdriver is essential, otherwise the screw will be damaged.

Jet


Honda mower carburetor Honda mower carb Honda carburetor clean mower carburetor jet

The brass main jet seen in the top picture, needs to be pushed free.

Take a suitable screwdriver and push on the jet, to free it.

It will may need further encouragement, tap on the jet housing as per picture, until jet is free.

Clean


Honda mower carburetor jet Honda mower carb

Clean the port holes of the jet and retaining screw  thoroughly. I use a strand of wire plucked from a wire brush.

The holes may look clean, but are dirty. After you have cleaned them, they will be noticeably bigger. This allows more fuel to flow to the engine.

Spray


Honda mower carburetor jet Honda mower carb

Spray all carburetor ports liberally with carburetor cleaner, fuel inlet, float needle seat, jet, throttle plate, choke plate and any other ports you can see.

Reassemble jet, screw, float and needle.

Rebuild


Honda mower carburetor jet Honda mower tank Mower gas can

Reassemble, fit the jet, screw, float and needle. Careful when fitting the gas bowl, the large o ring can become pinched, apply some oil to help it seat.

Don't overtighten the bowl, it causes it to leak.

Refit carburetor to the mower. Take special care when fitting the gaskets. Check your reference pictures.

This bit gets overlooked, but it's important. Clean out the fuel can and your gas tank. Check it for grit and if you're not sure the gas is good, replace it.

Fill with gas and turn on fuel. Fit spark plug wire, and you're good to go. Nice Work!

Gas Flow

This section deals with a lack of gas flow from the carburetor. The areas for consideration are: gas cap; carburetor float needle seal;fuel filter; fuel tank; fuel lines.

 

If you have too much gas flow, the float needle is at fault, and yes you could replace the needle but often this doesn't fix the problem. I like to replace the whole carburetor.

 

Small engine mowers use gravity flow to get fuel to the carburetor. Meaning the fuel tank should be higher than the carburetor. To test for flow make sure you are on level ground and have a minimum 1/4 full fuel tank. Common reasons for no fuel flow are bad gas cap and dirty float needle seals.

 

 

Remove Bowl


Honda mower gas flow Mower gas cap

The best way to troubleshoot no fuel flow is with the fuel bowl removed.

A fuel tank needs to breath. When fuel leaves the tank it needs to be replaced with air. A sealed tank will prevent fuel from flowing.

Remove the cap and check flow.

Gas Tank


Honda mower gas tank

Honda use a mesh screen in the bottom of the fuel tank to filter the gas.

Look in to the gas tank, which is easier when it's empty, and check the filter for grit. ​​

I use a suction pipe to clean the bottom of the tank, however sometimes you need to remove it to clean it thoroughly.

Gas Tap


Honda mower gas tap

Check if the gas tap is the problem, remove the gas line to the tap and check flow.

Float Needle


Honda mower float Honda mower carburetor needle Mower carburetor cleaner

Remove the float and check the needle seal.

Use fine wire to clean out the needle seat in the carburetor. I use a strand from a wire brush.

Blow some into the needle seat on the carburetor.

Fuel should start to flow.

Gas Bowl

The best way to troubleshoot no fuel flow is with the fuel bowl removed.

A fuel tank needs to breath. When fuel leaves the tank it needs to be replaced with air.

A sealed tank will prevent fuel from flowing.

Remove the cap and check flow.


Mower gas flow Mower gas cap

Gas Tank

Honda use a mesh screen in the bottom of the fuel tank to filter the gas.

Look in to the gas tank, which is easier when it's empty, and check the filter for grit. ​​

I use a suction pipe to clean the bottom of the tank, however sometimes you need to remove it to clean it thoroughly.


Mower gas flow

Gas Tap

Check if the gas tap is the problem, remove the gas line to the tap and check flow.


Mower gas tap

Needle

Remove the float and check the needle seal.

Use fine wire to clean out the needle seat in the carburetor. I use a strand from a wire brush.

Blow some into the needle seat on the carburetor.

Fuel should start to flow.


Honda mower carburetor float Honda mower carburetor needle Honda mower carburetor needle

Ignition System

Spark is just as important as fresh gas. When it comes to spark, your plug is the first component to check. So be sure to have a good plug on hand. In this section we will check the: plug; plug wire; coil; coil control wire; bail lever.

 

The test will require removing some covers. You don't need any special tools to complete this test, but I prefare to use a spark testing tool.

 

It easier to check solo and loads the coil to spec, I use the Oregon in line tester and you can check the price on Amazon. 

 

 

 

 

Float Needle


Mower repair tools Honda spark plug

For this test you will need a spare plug, any plug will do for the test.

But only fit Spark Plug (BPR6ES) to a Honda gcv 160 and 190. 

You will also need a plug spanner, insulated pliers and a very brave helper, who can withstand very high voltage....... Joking.

Plug Test


Mower plug Honda spark plug

Note: The best way to test spark is with the In Line Spark Tester tool or similar, as it will load up and stress test the coil.

Remove the plug from the mower and put the plug wire back on the plug. Now hold the plug against the metal of the engine using the insulated pliers, take care to ground it well.

The helper now attempts to start the mower while you observe plug spark. You should see a bright blue spark. If no spark, try the new plug.

There's 2 possible outcomes:

(1) No spark with either plug. If so keep reading.

(2) Spark is good, if that is the case, check out "Carburetor cleaning" and if that fails run a compression test.

Check Damage


Mower plug wire Honda spark plug cap

If you have no spark or your spark is poor you could have a faulty coil; spark plug wire; coil cap; short circuit of coil control wire or poor bail lever cable adjustment.

Look for obvious signs of damage. 

Throttle Stop/Start


Mower throttle Honda on/off switch Honda throttle cable Honda throttle cable

This is the throttle stop/start control type.

Most Honda mowers are fitted with stop/start control at the throttle lever and some have the bail lever stop/start, which is covered next.

The stop/start coil control switch see here, is mounted beside the carburetor.

Check that the switch is being operated by the linkage when you set the throttle to the start position.

If not, adjust the cable at the throttle lever.

Testing Throttle Switch


Mower on/off switch Honda plug

Truthfully, I don't usually test these switches, because they don't give trouble. So at this point I would go ahead and fit a new coil.

However you can test them by un plugging and repeating the spark test performed at the start of this guide.

If after running the test, the plug now sparks, replace the switch.

Still no spark, go ahead, move on and replace the coil.

Tools

For this test you will need a spare plug, any plug will do for the test.

But only fit Spark Plug (BPR6ES) to a Honda gcv 160 and 190.

You will also need a plug spanner, insulated pliers and a very brave helper, who can withstand extremely high voltage....... Joking, it's only moderately high voltage.


Mower repair tools Mower spark plugs

Spark Test

Note: The best way to test spark is with the In Line Spark Tester tool or similar, as it will load up and stress test the coil.

Remove the plug from the mower and put the plug wire back on the plug. Now hold the plug against the metal of the engine using the insulated pliers, take care to ground it well.

The helper now attempts to start the mower while you observe plug spark. You should see a bright blue spark. If no spark, try the new plug.

There's 2 possible outcomes:

(1) No spark with either plug. If so keep reading.

(2) Spark is good, if that is the case, check out "Carburetor cleaning" and if that fails run a compression test.


Mower spark plugs Mower spark plugs Mower spark plugs

Damage

If you have no spark or your spark is poor you could have a faulty coil; spark plug wire; coil cap; short circuit of coil control wire or poor bail lever cable adjustment.

Look for obvious signs of damage. 


Mower coil wire Mower plug wire cap

Throttle Stop/Start

This is the throttle stop/start control type.

Most Honda mowers are fitted with stop/start control at the throttle lever and some have the bail lever stop/start, which is covered next.

The stop/start coil control switch see here, is mounted beside the carburetor.

Check that the switch is being operated by the linkage when you set the throttle to the start position.

If not, adjust the cable at the throttle lever.


Mower throttle lever Mower on/off switch Mower cable adjustment Mower cable adjustment

Testing Throttle Switch

Truthfully, I don't usually test these switches, because they don't give trouble. So at this point I would go ahead and fit a new coil.

However you can test them by un plugging and repeating the spark test performed at the start of this guide.

If after running the test, the plug now sparks, replace the switch.

Still no spark, go ahead, move on and replace the coil.


Mower on/off switch Mower plug test

Bail Stop/Start

This is the other type stop/start system, the bail lever, and is connected to the engine brake which incorporates a simple stop/start switch.

When the lever is released a brake block pushes against the flywheel slowing the engine down. At the same time the simple stop/start coil control switch is operated.

Check that the switch is being operated when you pull the bail lever. If not adjust the cable.


Mower throttle lever Mower on/off switch

Bail Stop/Start


Mower bail lever Honda on/off switch

This is the other type stop/start system, the bail lever, and is connected to the engine brake which incorporates a simple stop/start switch.

When the lever is released a brake block pushes against the flywheel slowing the engine down. At the same time the simple stop/start coil control switch is operated.

Check that the switch is being operated when you pull the bail lever. If not adjust the cable.

Testing Bail Switch


Mower on/off switch Honda plug

So at this point I would go ahead and fit a new coil, because I have never fitted one of these switches.

But you can test the switch by un pluging and checking for spark as before.

If after running the test, the plug now sparks, replace the switch.

Still no spark, go ahead, move on and replace the coil.

Coil Replacing


Mower cover Honda engine cover Honda gas tank

Your engine may look different but this process will be the same.

Remove plastic pull assembly cover.

Remove pull assembly held on by 3 nuts.

Fuel tank is now free, take this opportunity to clean it if needed, otherwise no need to remove fuel line, just set it to the rear of the engine.

Remove Coil


Mower coil Honda engine coil Honda coil

Remove two bolts that hold the coil in place. Remove the coil control push on wire connector, under the coil.

Fit Coil


Mower coil Honda engine coil Honda coil

Fit push on wire connector and bolt the coil in place, but don't tighten yet.

An air gap must be maintained between the coil and the flywheel.

A business card is just the right size. Push the coil snug against the business card and tighten the two bolts.

Remove the business card.

Rebuild in reverse order.

Don't forget to refit the push on wire connector and turn on the gas.

Nice work!

Testing Bail Switch

So at this point I would go ahead and fit a new coil, because I have never fitted one of these switches.

But you can test the switch by un pluging and checking for spark as before.

If after running the test, the plug now sparks, replace the switch.

Still no spark, go ahead, move on and replace the coil.


Mower on/off switch Mower plug test

Coil Replacing

Your engine may look different but this process will be the same.

Remove plastic pull assembly cover.

Remove pull assembly held on by 3 nuts.

Fuel tank is now free, take this opportunity to clean it if needed, otherwise no need to remove fuel line, just set it to the rear of the engine.


Mower cover Mower pull assembly Mower gas tank

Remove

Remove two bolts that hold the coil in place.

Remove the coil control push on wire connector, under the coil.


Mower coil Mower pull assembly Mower gas tank

Fit Coil

Fit push on wire connector and bolt the coil in place, but don't tighten yet.

An air gap must be maintained between the coil and the flywheel.

A business card is just the right size. Push the coil snug against the business card and tighten the two bolts.

Remove the business card.

Rebuild in reverse order.

Don't forget to refit the push on wire connector and turn on the gas.

Nice work!


Mower coil Mower coil Mower coil