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Honda IZY 4.5HP Easystart - Cuts out when hot?

The mower starts first time on choke. After about 3 or 4 minutes, it begins to miss fire, and loses power and stops with popping noises - yesterday it fired back through the carb and blew the air filter off. It will the restart immediately (occasionally needs choke even though it is hot) but will fail again within 30s - 1 min. The carb has been stripped and cleaned but was spotless anyway - no difference. Could this be a sticking inlet valve causing the burnt gasses to be push into the carb, reducing power? - Does the head need to come off??

JFW
March 2007
Hi my izy will not start when warm for love nor money! From cold great once it has bern running will not start the plug is always wet got to leave the thing for half hour then it goes perfectly! Any sugestions

Mike
October 2015
A new NGK BPR6ES spark plug has not worked, but just wanted to say that I bought mine at Eurocar parts for £2.15. Check first on their centralised number that a local branch has one in stock and reserve it.

MCB
April 2015
I would like to offer a big thank you to everyone who posted on this site I wish I had seen it sooner,I had the same problem as most of the people on the site, changed the plug and it is back to being has good as new

joltter
March 2015
Well, I use a izy as a main mower in my work. Just as above, changed the plug over and is running great again. :)

Lee
October 2014
My Izy, was starting and cutting out within a second or two. Then after leaving it sit for a 20/30 seconds. It would do the same again. Sounded like fuel starvation, but on reading this post I decided to change the spark plug first. But that didn't work. So I took the carburettor apart and found a load of guck in the float chamber. Cleaning that fixed the problem. However, in hindsight there is no need to remove the whole carburettor to clean this chamber. It is held in place by a 10mm stud in the centre of the base. It can be removed easily with the carburettor in place.

Kieran Egan
June 2013
Hi, Im a proffesional in garden maintenance. I have my IZY mower since 2003 and used it regulary for domestic gardens. It is the best mower you can buy. You should change the spark plug and oil at least every 6-12 months. Apart from that my IZY has hardly had any maintenance/money spent on it. However it now has developed this very problem. Specialist Honda places are very expensive, so I took it to a very, experienced maintenace mower business. The problem was it needed a new starter coil. They fitted a re-condition one off another engine for me (£60). Problem solved. Should get plenty more years use out of this excellent machine now

Richard
June 2013
OMG !! Is was the plug ! Wish I had read this weeks ago ! Halfords now sell the individual if and not just the pack of 4.

Chris Martin
April 2013
I have a kind of similar problem with my Izy.

I have had mine for about 6-8 years and it has always started first time every time. Usual operating procedure for mine has always been, cold start on choke, run on full throttle, close throttle, engage brake, then to restart put back to full throttle.

However this year it started refusing to warm start whilst warm unless I used choke, also it now stalls on closed throttle. Although on full throttle it still seems quite capable of cutting the lawns.

I have tried all these tricks so far
-Replaced air filter
-Replaced spark plug
-Replaced fuel
-Ran on high concentration Redex
-Poured Redex directly into Carb.
-Put Carb cleaner through Carb.

It will now sometimes warm start without choke but still will not tickover on closed throttle.

Ideas anyone?

Cheers

Baz

Baz
July 2012
I had exactly the same problem.

Before you start dismantling it, buy a new spark plug from eBay for about £2.

It's 99% going to be the built-in resistor in the spark plug that's packed up.

Naz Nomad
July 2012
Self Propulsion Problem.

Could be a simple thing. Check behind the blade (make sure you take lead off spark plug as you dont want to lose your hands) and check if the the drive belt has come off (it will be slack). If it has and is not broken, simply put it back on the pully (get one side in the groove and turn blade). My Izy does this quite often as I have lots of twigs in garden and they tend to knock it off.

Clive Davison
June 2012
Cutting out so I changed the spark plug no difference
I replaced the carb and now it runs like new.

The1beard
June 2012
Hi, I have got the power model which moves forward on its own when the drive clutch lever is lifted. I have just found that that mechanism has stopped working. Without that self-propulsion mechanism, the lawn mower is too heavy too use. Does anyone know what the cause might be.

Gom
April 2012
Very grateful to you all, I'd cleaned carb and was about to take the machine to an (expensive) specialist. New plug and problem solved. It was behaving exactly as in the initial question- 90 sec running, bang- and stop. Restarting again in seconds.

Merseadoc
April 2012
Thanks to all,
I too was convinced I hard a carb problem - Starts and runs for 10 seconds then backfires and stops. Spent 2 hours stripping everything, then did a websearch and saw all your answers to this problem.
Ordered 2 new spark plugs - fitted new plug - now it doesn't miss a beat - Brilliant
The original spark plug was 9 years old.

Ian S
March 2012
Had the same problem the honda dealer said the carb was worn out 3 years old ! and the price of a new carb was more than what the mower was worth. Checked this site and replaced the spark plug, what do you know it works like it did when it was brand new. Thanks saved me £250.

Bob
March 2012
Thanks for the info. about changing the plug, I just spent an afternoon trying to fix what I thought was fuel starvation. Changed the plug, presto! good as new.
Well done all concerned.

Derek
March 2012
Miracle of miracles. Yep, fitted new plug and mower runs like new. Just shows the power of the forum!!

mickymower
March 2012
i am a RAC patrol and when i read all the threads regarding spark plug i laughed,im doing non starts on cars every day and very very rarely change plugs.....
I'm now eating humble pie CHANGE THE PLUG!!!!! it works. I had the whole carb in bits,realigned coil pack but to no avail. The plug was the problem..
also drilled a small hole in cap

RACMAN
March 2012
Hi,
yes once again air filter and spark plug change did the trick !

David
March 2012
I'll just add to the chorus so far of users who've had the cutting-out-when-hot symptoms, which seem like fuel starvation, but are cured by fitting a new plug. Took me a year of increasing frustration until I found this discussion and solved the problem! Thanks all.

Dick.
October 2011
My mower has only started and run on full choke. It is at least 7 years old but had it's first service in 2010. Slightly surprised that the man found that nothing needed doing or replacing. I replace the fuel after each winter but will now drain the carb by running with fuel tap closed on the final cut of the autumn.

Just ran out of fuel mid-cut and after refill with fresh it wouldn't start or even fire. Plug sooty, so cleaned with emery paper without any difference. Got my wife to pull the cord while I held the plug against the block to observe spark, which seemed OK but no idea what the gap should be. Plug slightly wet, which shows fuel coming through. After another 45 minutes of failure, I dumped the petrol by inverting the whole mower; can't seem to disconnect the fuel line easily to drain properly. Put the rest of the fuel can in the wife's car (mine is diesel anyway :) and bought fresh again; no change.

After reading the many helpful comments on this forum, I went to a local car parts place and bought a new plug; the non-resistor version BP6ES for £3. BINGO! Loadsa black smoke for a few minutes but now runs in all throttle positions including idle without cutting out.

I will try and check the carb for residue and crystals ... seem like you have to remove the air filter bolts to get at it.

Grass cut and can now return to the Walker Cup.

Sep 2011

Tom Wilson
September 2011
Had the same problem it would start and run for approx 30 secs and then cut out did all the normal sfuff but found the problem to be with the small black rubber hose from the carb it had rotted at one end a bit tricky to get your hands on but the solution was to remove the small hose then trim of the rot and replace but i put it in the reverse way around i found that it fitted better, once all back together and a good clean all around not had any problems since. Hope this helps anyone

peter
August 2011
Hi,

My IZY was working fine last week but now will not start at all. I've changed the spark plug but it's made no difference.

Any idea on what I can do to get it started please? The mower is around 5 years old and I have to admit to no maintenance....

Simon Dent
April 2011
Just found this forum after scratching my head for 20 mins working out why the mower wouldn't work, especially as she was working ok yesterday! Fortunately my Mazda uses the same spark plug as the Izzy, so put a different plug in (not a new one, just a used one from the car) and she's as good as new. Thanks everyone :-)

Rob
April 2011
Guess what... following winter storage Izy starts then cuts out after a few seconds.

Installed new spark plug and she's up and running again!

Jeff
March 2011
Thanks to those who pointed out the need for a new sparking plug.

Last year, mine had taken to stopping after 30 seconds regardless of whether it was on full revs or the slowest speed or whether it was in use or stood on the drive.

It would re-start striaght away and run properly for another 30 seconds.

It seemed like a lack of fuel flow and I did put a tiny hole in the cap but it made no difference.

Left it over the winter - checked it again and it was still doing the same thing as regular as clockwork. Fitted a new spark plug ... problem solved ... celabrated by giving it a good clean.

Thanks again,

J

Jamie
March 2011
Sorry, I made a mistake in an earlier answer. NGK BPR6ES spark plugs are ALL fitted with a resistor (which is what the "R" means of course!). The non-resistor version is BP6ES.

I've also had second thoughts about recommending a spark plug without a resistor for the Izy mower. It is just possible (though I think unlikely) that the absence of a resistor might upset the electronics.

Perhaps best, after all, to fit a BPR6ES and be prepared to renew it every so often.

Another David
December 2010
I've just noticed the comments from Jon Duke (July 2009).

Jon believes the fuel tank cap should have had a breather hole in the centre, but this is not the case. The dimple in the centre of the cap is just a moulding mark, not a missing breather hole. On the Izy, the cap breathes via the screw thread that retains the cap to the tank.

As Jon says, there is a small disk of felt in the centre of the cap. This connects the air space in the tank with two grooves moulded into the cap. Those grooves lead outwards from the centre of the cap to the screw thread, this being formed such that air can pass along it, i.e. between cap thread and tank thread.

Another David
December 2010
I doubt if the cutting-out problem is ever due to the fuel tank cap, and it is also unlikely to be due to dirt in the carburettor. Sorry David (May 2010) but I don't believe Redex is of any benefit to a modern engine - and please don't use Easystart as this will cause rapid engine wear.

As others have said, the usual problem with Honda mowers cutting out when running is failure of the spark plug. If the NGK plug has an "R" on the side it has a built-in resistor, and it is this unseen part that fails.

A replacement spark plug without a resistor will overcome the problem and will be cheaper to buy. What is needed is a plain NGK BPR6ES as fitted to several car engines.

The resistor was provided to reduce electrical interference but I doubt if running without one will cause any problem to anyone.

Another David
December 2010
Many thanks for the advice. The mower (bought 2001) started to play up last summer, with all the symptoms described. My wife couldn't start it, so I've been mowing the grass myself ever since, nearly pulling my arm out of its socket at each session. Yesterday it cut after just 10 paces, and then would NOT respond. I had just chosen its replacement, and about to click the "Add to cart" button, when inspiration struck, and I found this web page. The new spark plug (just £3.14) worked for me like a dream. The fuel cap vent was clear, but a 2mm hole provided a positive bleed. I didn't realise how much power it had lost. Now it fills up the grass holder again, so higher productivity.
Just one tip: be sure to get the correct spark plug - the "fits most mowers" ones you see in garden centres and the like usually have a shorter reach than required.
Now I'll treat it to a new fill of oil, before the winter lay-up.

Fred Pell
October 2010
The only problems I have experienced with my IZY - (six years old) is that it is prone to getting water in the fuel over winter - don't know whether this may be due to condensation - empty out the fuel into a suitable container - and I mean tip ALL of it out you will be able to see the beads of water at the bottom. Ideally store without fuel in the tank in winter - occasionally clean the plug properly with a small wire brush, file the spark surfaces clean and check the gap.

Mike Barlow
August 2010
I'm a landscape gardener who bought an 18" honda izy 2 years ago. Mine repeatedly hunts up and down and fouls the
the spark plug, it soots up within minutes of being cleaned. Took it to a local dealer who said straight away, "you need a new air filter" he put one on and it ran perfect. its now on its fourth and has started hunting again, I'm thinking of calling it Prince Phillip...

Paul
August 2010
i bought mine new 2 years ago 21" as a professionall i need a good mower for my job, however it would run perfect for short periods of time then cut out, sent it back to honda under warranty, they repalced the carb, and performned a service, sent it back to me, it ran fine for about 3 hours further useage and then started again, i was told by one of my customers actually, whose lawn was half cut when it stalled and wouldnt start that he had an old honda motorbike that had had a similar problem, all he did was drill a tiny hole in the fuel filler cap of the mower and 2 years on its still running like a dream, it works also by simply loosening the cap slightly.

mark
June 2010
Another Izy - same problems! Except ours wouldn't start at all.
1. Checked air filter - OK
2 Replaced spark plug as a precaution
3. Emptied fuel, added fresh
4. No better - still wouldn't start
5. Used Easy Start in the air intake, started straightaway
6. Added Redex to fuel once engine started so it would pull some through the carb and clean the jet
7. It happily ran for an hour while I cut the lawn

Problem solved.

Honda IZY 4.5HP Easystart - is the clue in the name??

David
May 2010
THANK YOU FOR YOUR ADVICE.
I had exactly the same problem with my machine.
Cutting Out,after running for 50 seconds, Backfiring on immediate attempts to restart. However after 4 or 5 Minutes the machine would restart on first pull in the choke position. then invariably cut out again after 50 seconds.
After reading the advice of fellow HONDA 4.5 HP m/c owners
.I drained the old fuel and replaced with new.
.I cleaned the air filter.
.I replaced the spark plug £3.65
This resulted in my m/c being ready to Rock and Roll again for another season.
THANK YOU.
Maurice Howie.

Maurice Howie.
April 2010
Yes its the spark plug. Was surprised to see it was as the old one was only mildly sooted. Changed it and it was as good as new. Poured redex down the plug hole before also and left it overnight to flush it out.

Shame halfords only sell spark plugs in boxes of 4!

Alex Miles
April 2010
I have had an IZY 18" self propelled now for 7 years, no problems until the first mow of this year, started ok on choke (third pull), ran for 2 minutes then stopped, after a couple more minutes started again ok then ran for 30 seconds and conked out again.After numerous repeat performances my right arm packed in. This was seriously denting Honda bulletproof reliability. I checked the plug (a bit sooty but the right gap).Then I looked at this website and saw references to failing plugs and blocked petrol filler cap holes. I couldnt believe it was so easy. Couldnt be bothered to brave the traffic for a new plug so drilled a very small hole in the plastic filler cap and tried again, It really works, finished off the rest of the lawn (Quarter acre) no problem. Sometimes the simplest answer is the best. Thanks for top advice
By the way my previous mower was a 16" IZY that I gave away to a friend after 14 years service, same oil, same plug, no maintenance, thats Honda reliability for you.

john c of Newbury
April 2010
Same issue. Changed spark plug running great

rbh
March 2010
The Izy eats spark plugs, always replace first as its the easiest job. Had one today that starts first time on choke then hunts (brrrmm brrrmm) revs rise then fall, only would run on choke. dirt in float chamber underneath carb. remove bowl unscrew main jet in the central tube, blow out with pump, on top of carb remove brass throttle stop screw, brass screw under that reveals the pilot jet, blow out with pump, I used foot pump fitted with tubless tyre valve for a good seal, when air comes out of carb mouth, replace all, will then run. always turn off fuel, run carb dry at the end of using mower as the fuel evaporates leaving residue and crystalls, a shot of Redex now and then works wonders to keep it all clean

old Pete
March 2010
My buddy services these things for a living.
A few tips.
Leave old fuel in it over winter - it won't start. Always use fresh fuel.
At the end of the season, I always shut off the fuel and let the engine run until it cuts out. That way old fuel is not left in the carb.

The Honda 4.5 will not start unless full choke is used.

If you do strip the carb - to unblock jets - use an air line, the canned air just doesn't do it.

Ade
February 2010
I have the Honda 535 electric start and was experiencing similar symptoms - it would start then just cut out within 20-30 seconds - no caughing or spluttering - it would just cut out - it loked like fuel starvation - checked the fuel and the cap - assumed it was to do with the throttle linkage - looked on this site and even though it made no sense to me at all (since the mover started perfectly and ran well for a while) decided that the fastest thing to try was the spark plug -

Changed it and it just runs perfectly!!!!

Would NEVER have guessed that.

Thanks

Paul from Poole
November 2009
Hi, I have had my izy since March 09 and have had similar problems to those listed below - spluttering, backfiring etc. It has been to dealer twice. First dealer said that it had been tipped on side - pretty sure it hadn't! Second dealer said that Isy has a problem with the choke system. Unfortunately design fault and reoccuring. Interesting to read previous comments as will try this when reoccurs. Mine has now developed a problem with SP so not too happy with the machine at all.

Jazz
July 2009
We bought our Izy earlier this year. It has this habit of most times, after about 5 minutes of running, getting into a stage where the engine surges, then cuts back repeatedly, and after about 2 minutes of this, it cuts out altogether. The inside of the exhaust outlet is black, indicating that the mixture is, at least some of the time, too rich. This could be significant, but I don't think it is (read on). I took off the air filter as per one of the other replies, and could not say that it was definitely faulty, so I looked at the petrol filler cap. Inside there is a rubber washer that behind it holds a porous small cylindrical sponge block. The rubber washer has a hole in to. The petrol cap has what looks like a hole in its middle, but in mine the hole did not go right through the cap, so I drilled it out with a very small (about 0.8 mm) drill. The cap will now let air into the petrol tank as petrol is used up. I haven't used it since this work, but I expect it to behave better. I really do think that when one buys a top price mower from a top engine comapny on should expect better than this. Next time I will probably investigate the cheaper options. My confidence in Honda is shaken!!!!

Jon Duke
July 2009
Same engine fade as above.........decided to attack the carb...........found this website................change plug instead.................shop had only a high temperature type............seemed sensible choice................izy going like a train.

Thanks everyone

elbee
June 2009
I've had the same problem, from new (2007) I always felt that this mower was underpowered. It's spluttered and stalled completely this weekend. Followed the advice below and tried with the fuel cap off - Result - it's like a new mower. I'll get a new spark plug to complete the job. Thanks to all just saved at least £50 at the local mower service centre....

Robin A
June 2009
I seem to be getting a similar problem. Starts fine on choke but then when it warms up I move it off choke to full throttle position. Up to today it would run fine (brrrrrrrrrrrrrrrrrr etc.) but now it goes into brrm brrrm brrrm brrrm cycle which eventually leads of chugging and death. Tried it without the fuel cap on, same problem.
Only runs smoothly if I run slightly on choke, too much choke and it chugs, too little it starts this "brrm brrm brrrm" business.

Toby
June 2009
Had the same problem. Would run for 30 secs and stop. Then restart quite easily, run for 30 secs, chug, cough and stop again.

Swore it was a fuel issue, stripped carb, cleaned and blew out everything with carb cleaner. Still the same.

In the end it was the spark plug as suggested here. Never would have thought that this behaviour was spark plug related, but it was. Runs lovely now.

Jef L.
April 2009
I had experienced this problem for the past couple of seasons (my mower has been in use for about 7 years with no maintenance!) it was solved by replacing the spark plug. Definitely worth a try as it is an easy fix.

Mike Protheroe
April 2009
hi, i've had trouble getting mine started for a couple of years now, dragged it from the shed today and it's having none of it! checked the fuel, cleaned the plug, nothing! just been looking on the web for spare part suppliers just in case its the coil and cant find any???
any suggestions?

thanks

lee
April 2009
I was having a similar problem to some of the posters on this thread, namely, the mower running for thirty seconds and then cutting out. I tried draining the fuel (as this was the first outing of the spring) and putting fresh fuel in but to no avail. Eventually, I went to Halfords and bought a small bottle of Redex (£1.29) this seemed to do the trick in flushing out any dirt or contaminants from the fuel system.

Grant
March 2009
Thanks to everyone - mine started playing up late last year. So yesterday I stripped n cleaned the carb, pipes, tap, tank, no obvious signs of any dirt etc. No change.

Found this today, so whipped out the plug - slightly oily black. Ah Hah! New plug in and it's fine.

Condition of plug suggested it was running a bit rich, so had a look and on the full throttle position it was just touching the choke lever and closing the butterfly slightly. So, I've moved the cable outer in so it no longer touches the lever* - time will tell.

* Undo the cross-head screw where the cable joins the linkages bracket, remove the clamp 'cos it's got a locking ridge, set handle at full-throttle position so it finds it's own position and replace the cable clamp.

Pete
March 2009
Please can you tell me what spark plug gap should be used on my 4.4 hp Honda Isy

Rod
September 2008
Thanks everyone. I had exactly the same problems as you describe. Cleaned the carb/tried running without the fuel cap but just the same. Thought I'd need to buy a new mower. Then read your notes yesterday, replaced the sparkplug today and it runs better than ever. I hadn't realised just how much power I'd been losing over the months.

Absolutely Brilliant advice.

JSE
August 2008
Found the answer - I simply replaced the plug - runs like a dream

JFW
August 2008
Further to my posting in June, I appear to have solved the cutting-out problem by drilling the small hole in the filler cap. I'm not totally convinced it's the perfct answer as when I start the mower I fill a reasonable sized garden with clouds of white smoke until the engine reaches it's operating temperature. I feel something isn't right somewhere down the fuel system. Any ideas?

john G
August 2008
Had exactly the same problem. Runs for about 30 seconds, worse when you load the blades by mowing, then starts to stall, spluttering, popping. Would seem like fuel starvation ? So tried the idea of removing the fuel cap - no good. Tried running with no fuel cap and no air cleaner - no good. Cleaned the
plug (which looked ok, but a little black) - no good. So replaced the plug - Problem solved!! Would seem that it was just the plug
(which looked fine but obviously wasn't). Mine was a 2002 Honda Izy which had only been used for 2 seasons out of the 6.

ljs
August 2008
Just having same problem with brand new Izy with automatic choke. Been back to main dealer twice and they have been unable to solve the problem - I'm not too sure they believe there is a problem. I've just found out that unscrewing the filler cap when it starts to labour soon re-establishes correct engine speed, but as I use it quite a lot it's not very convenient. I'm afraid to keep the cap loose all the time as I would undoubtedly lose it, so I have simply drilled a small hole in the centre of the cap which I'm hoping will have the desired effect, as I have no doubt invalidated the warranty. I'll let you know.

John G
June 2008
Had exactly these symptoms. Remove the air filter which exposes 3 off 6mm screws (10mm heads) remove all three (two long ones hold carb onto engine) and the plastic housing, this exposes the choke flap which in my case was stuck partially closed. Clean the mechanism with a solvent cleaner to remove soil and grass debris and operate the choke lever repeatedly. Then clean the spark plug with a wire brush and solvent. Job done

kevin fletcher
June 2008
So glad I found this forum. I had the same spluttering of my Honda Izy, with it eventually cutting out. I just loosened the fuel cap slightly to allow the air to flow and it has worked perfectly since.

FTM
May 2008
The 30 seconds cutting out problem is probably a blocked fuel cap breather. My Honda mower suffered with this until I inspected the cap and found that the breather hole had not been punched out properly during manufacture. clearing the breather hole cured the problem. So as mediaguy suggested - try running with the fuel cap off as a quick check.

Taff
May 2008
Hello... at the end of last season I had the same cutting out problem as others here.

The mower is just years old and needed a service.

Amongst other things they replaced the spark plug... after 3 uses this season the same old problems is back!

After reason the stuff here about fuel and air it made me think the engine is somehow being starved or petrol.

I slightly loosened the cap and now I the problem has gone! Try it!

BE CAREFUL THOUGH... the cap can work loose and drop off.

Good luck.

Mediaboy
April 2008
Having sort of same problem. Izy will start easy enough but then stops after 30 secs. Leave it for a minute and it easily starts again, then stops again afte 30 secs. Everything points to fuel starvation, but it's fine. No idea what the problem is. I have tried everything.

Dave
April 2008
Hi, we had the exact same problem with one of our Izy's...cutting out on us when hot and only starting up again once it had cooled down. Ours is a brand new machine and I think it was down to the engine 'breaking in', as after a few times of this happening to us it's stopped doing it now. It did 4hrs of non stop mowing the other day after having these problems after 10min or so...so i'd say just bear with it.

Pristine Gardens
March 2008
I think I've got it sussed, John M got the answer - 'It ran OK with the petrol cap off'. The fuel tank is becoming sealed & so is starving the carb of fuel. check the Fuel cap - there is an air way, if this is blocked then the tank gets pressurised & fuels refuses to flow! Clean the rubber seal & make sure the airways are not blocked - I think the seal must go on a particular way round to give an airflow. I will sort mine out & let you all know.

Carl

Carl S
March 2008
Hello, John here again, tried the Honda this morning and same problem but only twice. I still think it runs out of fuel after 30 secs, a carburetter bowl do you think ? Anyway I decided to bounce the Honda up and down on the path whilst it was still running and it kept going. I am going to Halfords and get some additive for the petrol that might deal with a float and needle problem in the carb.
John

John M
February 2008
Feb 2008
Just got my very lightly used Isy 4.5 out, running OK in Oct 2007. After 30 sec running at full revs started to cough and stop, started again after about 30 secs but with same result, this for a further 6 times. Suspected fuel starvation, checked air filter, OK, cleaned plug (dirty) same reslut. started to dismantle air cleaner housing to look at carb and thought, Hey there can't be anything realy wrong so tried again, same result but it would run longer on part throttle ! I had filled with fuel so ran with fuel cap off, result, could it be an air lock ?
Mowed lawn no problem. I use Mobil 1 syn from new. JOHN

John M
February 2008
Just had my Izy apart for the second time having left the lawn half mowed!! Cleaned sooty plug, removed and cleaned carb and checked air cleaner, which looks fine. Although it sounds like fuel starvation, I've checked the fuel flow to the carb and it's fine. I now suspect something electrical, so will talk to the local Honda dealer to see what they think before spending any money.

goggomobil300
October 2007
Had the same problem with my izy, seemed like fuel starvation when hot, leave for a minute or so, restart. Runs for a minute, splutters to stop.
Plug dirty with carbon. Carbon glows like a cinder when hot causing pre-ignition. Clean/replace plug. OK..........

Seems that the izy runs slightly rich but dosn't smell rich.

Del Griffith
September 2007
Hi, I had the same problem as well so:-
1. Checked the air filter (3 years old) seemed clean but replaced anyway.
2. Checked carb for contamination but it was clean as a whistle.
3. Replaced spark plug. The original was sooted up.
4. Gave the grass box fabric a thorough clean with the garden hose. The fabric was completely caked up and not "breathing".

Result? Success! Mower now runs just like new.

Ed
September 2007
am having exactly the same problem myself. Has been getting worse over the last few weeks. checked the spark plug and cleaned it (covered in carbon) cleaned the air filter (pretty clean anyway). started again really well, but then cut out within a couple of minutes! spark plug coated again in carbon. Have topped up fuel recently but not completely refreshed it. Any ideas?

John G
September 2007
Have exactly the same problem with mine. Spoke with a friend who also had same problem. He changed the high tension coil, spark plug and fuel - now runs OK. He does not know which of the 3 items was the fix! I am about to change the plug as this is easy to do - fingers crossed.

Tony
June 2007
are the valve clearances adjustable?. it may be the inlet valve is not fully closing therefore needing a richer mix to enable the engine to run. if the valve clearances are adjustable then set them correctly. if they arent adjustable and the valve seat is worn you can either renew the valve or do what i done and remove the valve and file a bit off the top to give you a bit of clearance. this worked with an old robins engine. good luck

mers
April 2007
Hello,

Recently had exactly the same symptoms (same model Honda) myself. I thought the petrol had gone stale so emptied the remains and drained the carb. However, I suspect the real problem may have been the spark plug - as a precaution, I changed this at the same time. Once done, it was like having a new mower again. Worth a try if you haven't already.

James Y
April 2007
Hi,
I'm having the same problem but I'm not really as technically proficient as you seem to be. From a layman's point of view I'm just wondering if it's been sitting over the winter with old petrol in it?

Have you had any joy?

Phillip Oliver
April 2007
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Mend Garden Tools, Lawn Mowers
Free repair help for Honda lawn mowers