petrol mower won't start - any ideas

[tosh]

As I previously mentioned I've finally decided to tackle my hoarding problem - I'm selling most of it.

We bought a Rotavator and petrol mower soon after we bought our house. Both were used briefly then stored at my parents house. They've been there for the past 13-14yrs in one of their  "dry" outbuildings.

Anyway, after a lot of bitterness within the family I've walked away, in turn they delivered back my stuff whilst I was out.

The Rotavator was sold 2 days ago, but the mower is still listed. I thought it would be simple to get going - but having just spent the past 6hrs I'm starting to rethink what I thought.

Its a Atco balmoral 14SE electric start. The battery is obviously flat and my family didn't think to bring the charger back too.
No worries, its got a pull start as well.

I knew it would be pointless using the pull start, so removed all the outer trims to expose the engine and drive shaft. The carburetor was removed and cleaned in fresh petrol using a soft paintbrush. The spark plug was removed, cleaned and put on the gas ring to warm up. I used a cordless drill with a socket on the driveshaft to turn the engine over.....nothing!!
Removed carb again, rinsed thoroughly in clean petrol then blew out using a 12v tyre inflator with a football needle fitted. The plug was again removed, heated and then refitted...nothing!!!
Removed plug and poured petrol directly in, reinserted plug and used pull start, rope snapped, but engine fired up and died immediately.

Spent the next 20min removing pull start and replacing snapped cord with new cord.

Again removed plug, poured in petrol, replaced plug - This time I used the cordless drill to turn the engine over...again fired up and died immediately.

Got out can of carb cleaner squirted directly into carb whilst turning engine over, again fires up but dies.

The mower should fetch good money if I can get it working - otherwise its not going to fetch anything. The condition is amazing considering its not been touched for over a decade.

Can anyone give me some ideas please.

[Mr. Whippy]

Can you get it to run, even briefly with starting fluid?  If so, the carb needs a rebuild and thorough cleaning, not just spritzing with the cleaner (petrol is getting to the carb, I'm assuming).  If it won't fire up with starting fluid, replace the plug with a new one and see if it will fire with starting fluid.  If not, then the engine may have a problem with compression, and doing a compression test, followed by compression test with a tablespoon of oil down the plug hole is in order.

It will tell you:

1. If the engine has proper compresesion.
2. If the compression is correct only with oil in the cylinder, then the rings are damaged
3.  If there's low compression with and without the oil, then one of the valves is leaking (suspect exhaust).

Also make sure there isn't an ant nest or mouse nest in the muffler. 

[NKlamerus]

Well, your either not getting spark or fuel or air. Sounds to me like like the engine burns whatever fuel your putting in the chamber and then dying when that burns off.

Therefore, I would bet your not getting fresh fuel.

Did you clean the tank out? Check for rust and water. Also inspect every hose. Sitting for that long I would definetly suspect some dry rot.

[HarleyXJGuy]

Sitting for so long I would always assume the carb is gunked up. Did you pull out the jets and look through them, maybe clean them out with a tine wire if they are big enough for that?

Also the plug was replaced with a new one? Not much chance I would think of reusing the old one.

Like Mr. Whippy said you can eliminate a lot of possible problems with a simple compression test. If you have good compression it is just a matter of finding out if it is Air, Fuel or Fire that is the issue.

Almost forgot, where does your spark come from you may have an issue with the wires or source of spark.

[tosh]

Cheers for the replies

Ok

Both 12v & 14v wouldn't even touch the engine. The 24v Bosch does turn it over but it knocks the hell out of my batteries!!

So I'm guessing compression is good??
I've probably had it fire up a dozen times but it dies as soon as the fuel burns up. I did keep it going for around 10-20 seconds by squirting carb cleaner directly into the carb.

The air filter is perished (foam) the fuel tank is plastic. Both float and bowl were covered in a varnish like substance - I'm guessing that's the old fuel that's evaporated?? I've cleaned the bowl and gently cleaned the float.

I agree - it seems as though the fuel from the tank isn't getting to the cylinder?

On all occasions when it started, there was nothing to suggest there maybe serious problems - no back firing, no blue smoke.....Nothing 

It should purr - like I said the condition is amazing.

Could it be the jet is clogged up with that varnish stuff?? But I'd have thought the carb cleaner would have dissolved any residue.

Edit

I haven't replaced the spark plug - simply because it does fire up. If I get it to run, even roughly I'll put a new plug in. But until I'm sure of what it is I don't want to start throwing money at it.

[HarleyXJGuy]

Oh no carb cleaner will not put a dent in residue if it is old enough. Are your jets the kind that can be replaced? Also if you can get a wire through them that sometimes works.

Please tell me you removed or replaced the inline fuel filter if there is one. Also there is often a screen or small filter at the base of the fuel tank that could be the issue.

Pretty sure it is a fuel issue though, just a matter of working through all the possible issues at this point.

[HarleyXJGuy]

I forgot to add this is all coming from my years of working on gasoline engines. Never worked with one that runs on petrol so take my advice with a grain of salt. 

[tosh]

Ok

Pictures...

[NKlamerus]

Pull the hose between the tank/carb and make sure it's free. Then take a light and look into the inlet on the carb. That should give you a good idea on how gunked up it may be.

I'm not recommending this by any means, but we used to "clean" the carburetor by taking the air filter and fuel hose off. Open the throttle and blast compressed air in the fuel inlet (where fuel would enter). Usually we could get most the mud out of it that way. But I doubt there is mud in your carb

[tosh]

The fuel line must be ok as I removed the float bowl earlier, the grips I put on the fuel line were obviously not tight enough as petrol was pouring out.

I'll shine a light into the inlet.

Would there be any benefit from removing carb and soaking for a day or so in a vat of clean fuel.

[PTRSAK]

From the symptoms you describe I'g be heading straight to the jets. Main and idle circuit.
If it sat for that many years the jets will have healed up from a combination of fuel residue and corrosion.

you obviously have compression and spark from the fact that it fires up on a direct prime of raw fuel in the cylinder. But it dies because the carby isn't supplying a continuous flow.

If you're just planning to sell it you can try cleaning the jets, start with soft materials like a toothpick and even up to fuse wire or other copper wire. Using anything to hard can enlarge the jets and mess up the tune.
If you plan to keep it, spring for a carby overhaul kit and replace all jets and seals.

[HarleyXJGuy]

From the symptoms you describe I'g be heading straight to the jets. Main and idle circuit.
If it sat for that many years the jets will have healed up from a combination of fuel residue and corrosion.

you obviously have compression and spark from the fact that it fires up on a direct prime of raw fuel in the cylinder. But it dies because the carby isn't supplying a continuous flow.

If you're just planning to sell it you can try cleaning the jets, start with soft materials like a toothpick and even up to fuse wire or other copper wire. Using anything to hard can enlarge the jets and mess up the tune.
If you plan to keep it, spring for a carby overhaul kit and replace all jets and seals.

That's what I already said PTR.

You just said it in a way he could understand. Showoff. 

[Crow]

Is that Tecumseh engine? As everybody is saying, jets are glogged. And must say, do not give compressed air through that carburator. There is couple seals and springs that will go flying if you do that.

[tosh]

Spent another couple of hours - still not running!!
My patience is beginning to wear.

Removed plug and check for spark on cylinder head - seems ok - so guessing that confirms
Compression, coil and plug can all be ruled out.

Again removed carburettor (tillotson) cleaned again in fresh petrol. Removed bowl, was expecting the bottom bolt on bowl to have holes in it??

The carb looks to be sealed - I can't fined away to open it. So removed this....

It was all gunked up. The tube is hollow and I assumed this sucked fuel up from the bowl and squirted it towards the cylinder. But having poked a paper clip down - it doesn't go all the way to the holes at the top???

Sorry - as you've all probably guessed I'm pretty clueless with engines.


 Update:

With nothing to lose - put that brass thing in a cup and poured boiling water in - loads of debris came out - left it for a few minorities then stirred it to dislodge any left. Removed and then blew down the tube with the end immersed in water - bubbles!!!

Ok I'm tempted to remove carb and do the same.....boil it!!

Yes or no??

[Crow]

No.

Find air jet, clean it, and you are good to go.

[lowtech]

Oh no carb cleaner will not put a dent in residue if it is old enough. Are your jets the kind that can be replaced? Also if you can get a wire through them that sometimes works.

Please tell me you removed or replaced the inline fuel filter if there is one. Also there is often a screen or small filter at the base of the fuel tank that could be the issue.

Pretty sure it is a fuel issue though, just a matter of working through all the possible issues at this point.

This and much of teh stuff mentioned before. Without any research I suspect the mower uses a vacuum operated fuel pump. If teh membranes are torn or hardened, the engine will not get enough fuel and die. If you found a varnish like residue, it will most likely still be inside the small orifices inside the carb body and will prevent it from workiong properly.

[tosh]

Well, perseverance paid off..... Got it going tonight, 1st pull too!! 

Having spent most of the weekend messing around with it, I gave in late last night and listed it on Gumtree for a paltry £85!! Within 2 minutes I had an email saying " I'll take that pal, txt me your address" Grrrrrr.

I just knew this guy would probably be a dealer and would no doubt get it going in no time and then sell on for a huge profit - I removed the listing this morning and had another go tonight.

Removed Carb, air box, manifold, exhaust. Sprayed carb cleaner into the inlet port incase valve was seized.

Next removed fuel bowl, also removed a brass nut from the opposite end of the threaded alloy cast tube where that brass rod in the picture above went, which turned out to be a clogged up jet!!

Boiling water and a sewing needle, then blew out with carb cleaner....getting giddy now!!!

Re-assembled everything and pulled starter....purred into life!!

Isn't that just the sweetest sound ever!!

Now she's running I'll give her a good service, new air filter, plug, oil change etc. clean her up, make sure everything's working may even pick up a new battery for the electric starter.
Will then relist around spring easter time. Hopefully will fetch good money.

There was also the scarifier cassette when I left it all at my parents. Cannot believe the price they are now fetching. Hopefully that will turn up along with the battery charger.


The most important thing I've learnt.....is don't give up!!

Thanks to everyone here for helping me get it sorted.
 

[HarleyXJGuy]

Very cool, so satisfying once you finally get it to run.

Lost count how many mowers, dirt bikes and four wheelers I have had to go through this process with.

[Mr. Whippy]

That is a cool mower.

Congratulations.  A lot of times on small motors, there is no non-destructive way to disassemble the carb, so the unit has to be replaced, if a good soaking doesn't sort it out.