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sasquatch
06-04-2012, 07:13 PM
Put a carb kit in my "weed Eater" yesterday.

After a number of pulls to start it, Got it to run, and adjusted the carb needle to where it ran smooth, Quick response from the throttle when opened, and nice smooth idle.
Shut it off a few times and it started first pull, idled beautifully. Cut with it for an hour. Then put it away for the night.

Went to use it today, and it just will not start, It has spark, but the plug appears dry, primer is almost full, but doesn't appear to be getting fuel now.

Any ideas ?? Thanks.

Toolguy
06-04-2012, 07:14 PM
Maybe it's out of gas?

Tel
06-04-2012, 07:17 PM
Not an Echo is it? Them dammed things don't need as reason not to run!

A.K. Boomer
06-04-2012, 07:18 PM
Check and make sure your tank vent is operable...
at least crack it open and listen for that vacuum sound.... if you hear that instead of pressure or nothing then you just might have it...

sasquatch
06-04-2012, 08:03 PM
AK Boomer, i'll check that in the morning. Good suggestion.

(The tank is full of fresh right outta the pump w/2 cycle mix.)

Strange it ran SO GOOD yesterday, idled beautifully, and restarted on the first pull three or four times.

lakeside53
06-04-2012, 08:14 PM
Check you carb mount screws also. Hopefully it didn't puke a crank seal.

Does your primer pull fuel from the tank and return the excess? Look into the tank to see or pull the return hose.

Willy
06-04-2012, 08:34 PM
Lakeside53 brings up a good point about the function of the primer.
I very occasionally have the same symptoms on my Stiihl trimmer.
I always look to see if the primer is returning fuel back into the tank.
If not I just remove the gas cap from the trimmer and blow into the tank while operating the primer, this always primes the primer and I'm good to go again.
Don't forget to bring along a beer to get the gas taste out of your mouth.;)

sasquatch
06-04-2012, 08:52 PM
Good points about the primer, and yes it is returning fuel back into the tank. I did notice the return line when i pump the primer has the odd air bubble in it?-The primer bulb is not completely full, just around half full all the time, which it was yesterday when it ran so good.
I will trying blowing into the tank though ,(carefully).:D

TGTool
06-04-2012, 09:25 PM
Jeez, giving a blow job to a weed trimmer! This place is getting weirder all the time! :eek: I think I'd need the beer(s) first. :D

Willy
06-04-2012, 10:05 PM
Jeez, giving a blow job to a weed trimmer! This place is getting weirder all the time! :eek: I think I'd need the beer(s) first. :D

Yeah I know, just remember to blow...don't suck!

A.K. Boomer
06-04-2012, 10:27 PM
AK Boomer, i'll check that in the morning. Good suggestion.

(The tank is full of fresh right outta the pump w/2 cycle mix.)

Strange it ran SO GOOD yesterday, idled beautifully, and restarted on the first pull three or four times.


Yes not saying it's it but it fits the bill with the little bit of info I have to go on --- Gas builds up it's own pressures when heated and jossled about,, but then all the sudden you let things cool and the tank is down and you start having fuel problemo's

It's a good start - many little two stroke fuel caps have a bicuspid type valve - it's like fish lips facing inward --- after setting an entire season and stuff like that they can become stuck together .... if you have this design give em a squeeze .

sasquatch
06-04-2012, 10:39 PM
Re: Fish lips facing inward: WHAT A DESCRIPTION!!:D :D

My cap isn't like fish lips, just got a piece of green plastic wedge of some sort. (On the inside, then a little hole on the outside with what appears to be a little brass vent less than 1/8th across. Tried blowing out out a bit ago, nothing seemed to happen, wonder if it's a pourus bronze or?
(I got a couple of spare caps from scrapped engines for parts, i,.m going to dissect a cap tommorrow see what is in there.)

A.K. Boomer
06-04-2012, 10:57 PM
Sasquatch, they are basically a check valve - they will not allow you to "blow out" but they should allow you to blow in...

sasquatch
06-04-2012, 11:06 PM
Tried blowing "In" nothing semed to give, (maybe my lip pressure was poor,):D going to investigate that in the morning, thanks for the help so far.

A.K. Boomer
06-04-2012, 11:09 PM
Yes - investigate - they do not need to vent much so you may be getting fooled -- but they do have to vent in some or you will gridlock your fuel supply....

atty
06-05-2012, 02:05 AM
For what it's worth....just had a round with my weed whacker that had been acting kind of cranky for a couple of years, but I just wrote it off to old age, both me and the whacker. Anyway, this year it finally got to the point that the only way it would start was a fuel prime with a syringe down the throat of the carb., then after a few rounds of that, it was fine. Primer bulb was also returning fuel, but I was not happy with how the bulb pressure was sounding. Decided enough was enough and started in on the carb. In the process I finally worked one of the fuel lines enough that it gave up the secret. An ever so slight crack right at the nipple where it goes into the fuel tank.

Even though the fuel lines looked OK, and I could see fuel traveling through, that's all the leak that it needed to take on a whole new personality. One that I didn't care for. :(

aboard_epsilon
06-05-2012, 06:06 AM
try puting a non resistor spark plug in it .....

works wonders for some stuff .

all the best..markj

Abner
06-05-2012, 09:06 AM
Mine has an in tank fuel filter. Somehow worse than my chainsaw for plugging with micro dirt I cannot see. :mad: I have done the carb kit too. Finally took a pocket knife to the filter screen and presto runs better than it ever has.

Disclaimer; The use of pocket knifes on fuel filters should be done for entertainment use only. Past results should not be used to gauge future performance.:p

sasquatch
06-05-2012, 09:17 AM
Thanks abner, i checked the in tank filter , i could blow through it , so presumed it was fine,--- hmm, i could try it without the covering on it, as i have a couple of spares.
(I did also change the fuel line during the rebuild),

Thanks all you guys for the help so far.

firbikrhd1
06-05-2012, 10:29 AM
Does it even try to run when you choke it? IF it does, perhaps you have the mixture screws adjusted too lean. It's easy to do with a hot/warmed up engine and happens this way, you get the thing started after a carb rebuild with the mixture screws adjusted to an initial recommended setting. Then after the engine warms up you readjust the screws and it runs great, but, it's possible to get it too lean so it runs really well at high RPMs. Then when you shut it off and leave it overnight it's far too lean to run when cold. It will pop or attempt to run with the choke on but stall. Try enriching the mixture screws 1/4 turn or so and see it that helps.

sasquatch
06-05-2012, 11:24 AM
It won't even kick, and each check the plug is dry.

One thing i did remember, was that in order to remove the gas tank, on these things you gotta remove a housing on the rear, as the tank screws are in behind that housing, anyway removing that housing exposes the inside of the crankcase, (which i didn,t know,) the gasket looked perfect so i put it back together with a little grease on the gasket.

However now i,m suspecting what someone mentioned back a few posts about a vacumn leak there, so again dismantled it, put some sealer on the gasket, and closed it up again.

See what happens now, i'll leave it sit for a few hours, gotta head to town.

flylo
06-05-2012, 11:33 AM
You can check the crank seal if you can make it run by spraying starting fluid on the seal if you can get to it. If the RPMs go up=bad seal. I'l take off the gas cap,put it on loose,lock the throttle open, choke it & pull. If nothing I'd remove the air cleaner, give it a small shot of starting fluid & pull. Most 2 strokes I start I switch on,pull choke,lock throttle till it fires,push choke & start then unlock the throttle. Good luck!

lakeside53
06-05-2012, 12:32 PM
You can also (as a test) gravity feed fuel to the carb. Small tank on hook about 3 feet higher than the carb, tube to the inlet. It should run that way even with poor crankcase integrity.

Did you change the fuel filter before you put on a on a new carb? Is the fuel inlet hose o.k. - leaks, crap, etc? Wouldn't be the first new carb to be blocked by old stuff. Also... new carbs can fail. If you open it, look for the tiny galley plugs (aluminum disks) on the metering side to be secure, and that the sealer hasn't flaked of and is blocking a jet.


In general, just putting on the choke will cause enough negative pressure to pull fuel even if you have a bad crank seal. Bad meaning "leaking"... if it's missing, that's another problem.

A.K. Boomer
06-05-2012, 01:27 PM
Yes all good suggestions esp. Attys about the hoses cracked and sucking air,

So did you replace the diaphragm pump in the carb? that thin spring loaded diaphragm is actually your fuel pump that runs off the crankcase pressure and vacuum,
if it's got a pinhole in it it will not pump fuel properly...

lakeside53
06-05-2012, 02:44 PM
hmmm... maybe I misread what you wrote, but the diaphragm is the metering side (think of an all-attitude float bowl) and acts on a spring lever that allows fuel to enter the chamber from the pump side; the fuel pump is a flat membrane typically with two small tabs that act as check valves for the pumping action.

The pump side rarely fails. If the tabs are curled up from the ethanol... then it won't pump. And... probably not this issue as it ran yesterday, but check your order of gaskets - it's reversed from pump to metering side.

A.K. Boomer
06-05-2012, 02:51 PM
Yes one's a pump and the other is the metering - the metering is connected to a needle and seat is it not?

the pump just has reeds or something like that- been awhile but im about to find out because I need to get my weedeater going before I get my annual clean-up-your-act letter from the city:D

lakeside53
06-05-2012, 02:57 PM
Yes, the metering diaphram is either connected, but more usually just in contact, with the lever that actuates the needle valve. It's not the fuel pump. The fuel pump side isn't spring loaded -typically flat mylar.

A.K. Boomer
06-05-2012, 03:02 PM
Right you are - not spring loaded - just uses the positives and negatives of the crankcase to get the job done...

sasquatch
06-05-2012, 06:58 PM
Well, the situation has now changed.

Today i went at it again , and yes i done most everything mentioned, changed the diaphrams, screens, new fuel line, changed the needle and seat, checked the fuel filter , on and on.

I got it to start kicking,, then got it to run three times for about 5 seconds, then it would again quit. Yes i was priming it with a squirt bottle through the carb.
Then Nothing, Just nothing, plug was now wet,(previously yesterday it would be dry,),, so in frustration,, (My right arm is getting a major workout!)
I check for spark, now there is None,, no SPARK!!

So, i,m scrapping the darned thing, and going to buy a new one!! This was a great snipper and lasted 11 years, time to get on with other projects.

So, a BIG thanks to everyone who responed to this dilema , much appreciated. You all were a BIG help.

A.K. Boomer
06-06-2012, 12:32 AM
What?

so that's it ? so la de da - we don't have spark so we just buy a new one ?

Really --------- ?

No ---- not really - this is the HSM ------ we don't buy new anything - we keep fixing the same crap over and over and we end up dieing with it,

that's what you do pilgrim -- you pick yourself up - you dust yourself off - get back on that Fuquing horse and ride that pig back into the ground one more time!!!

are you hearing me?

Dare i show u a pic of my 23 year old DR. Martin sandels complete with rivets - duct tape and reinforcing screws ------ what about my 50 year old Hoover that I have wired to kick in a secondary set of windings and would drag a dyson sideways at 30mph+

Get back on the fuquing horse or your a douche... (nothin but luv - A.K B., you can thank me later);)

flylo
06-06-2012, 12:50 AM
Better show a video of that thing running by the weekend or sounds like your in Biiiiiiiiiiiig trouble! :eek:

lakeside53
06-06-2012, 01:59 AM
Quiter... fix that POS! Remember how happy you were when it ran a couple of days ago? That joy can be yours again;)

No spark? Check the plug for a TINY sliver of carbon shorting. Check the HT lead is still connected to the plug clip. Pull the grounding wire off the ignition. If it runs, you have a short somewhere. Check the ignition-flywheel gap; should be about the thickness of a business card.

If all else fail, replace the ignition.

Krunch
06-06-2012, 06:17 AM
So, i,m scrapping the darned thing, and going to buy a new one!!

http://imgc.allpostersimages.com/images/P-473-488-90/60/6067/4OZD100Z/posters/michael-crawford-still-won-t-start-new-yorker-cartoon.jpg

A.K. Boomer
06-06-2012, 06:58 AM
Quiter... fix that POS! Remember how happy you were when it ran a couple of days ago? That joy can be yours again;)

No spark? Check the plug for a TINY sliver of carbon shorting. Check the HT lead is still connected to the plug clip. Pull the grounding wire off the ignition. If it runs, you have a short somewhere. Check the ignition-flywheel gap; should be about the thickness of a business card.

If all else fail, replace the ignition.


Yes - Yes - Yes,,, You guys brought a tear to my eye,

Sasquach your lucky my Pops ain't still around or you'd be catching an earful,

Test it with the plug out but grounded again - yank the cord in a dark room and look for arcing all along the plug wire and coil,
test the resistance on the plug itself, Your almost there......

think of all the beer you will be able to buy with the money you save - that's what pushes me on --- equate everything into your favorite 6 packs and how many --- that will give you the incentive to keep pushing on...

Were pullin for ya.

sasquatch
06-06-2012, 08:26 AM
Ha Ha Ha Ha!!!!!! You guys are GREAT!!!!!!!!!!!!!!!!!!!!!!!

Got some other projects to get done now, fooled enough time away on this thing,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,SO,,, I just put it aside for now.:rolleyes:

firbikrhd1
06-06-2012, 10:18 AM
Now that you are talking about no spark I'll relay a problem I once had. It may give you some ideas about your problem. I took a weed eater apart to do some work and had an intermittent spark issue after I put it back together. Turns out a wire going to the on/off switch had gotten crushed when I reassembled it. The insulation was damaged and it was intermittently shorted. I've also had switches go bad so it might be a good idea to check that possibility.

Peter S
06-06-2012, 08:18 PM
No spark? Got another spark plug lying around, anything will do just to see if you get a spark.

sasquatch
06-06-2012, 08:52 PM
YIPPPPEEEE! I now have spark again!!

A nice thin blue arc!! Bad connection in the wire.

Tommorrow going to pull the carb apart again, and will reseal the crankcase again.

Here's hopin!!:D

Don Young
06-06-2012, 09:10 PM
I don't recall whether your engine has a rubber one-way vent in the fuel tank cap. It could be one more thing to check. I believe you said you had checked the exhaust for obstructions. Those are the two obscure problems I have had with these engines.

sasquatch
06-06-2012, 09:14 PM
Don, i switched caps, i,m thinking this may be an enginevacumn/pulse problem from a leaking gasket, probably the crankcase.

I,m going to dismantle the carb again completely to check for any dirt obstructions etc, there's some very tiny holes in that carb.

sasquatch
06-06-2012, 09:17 PM
Forgot to mention, the tank holds pressure when i sit it in the sun for a bit, you can release the air, the vent in the cap should work that way to draw air in, but not leak fuel out i think.

lakeside53
06-06-2012, 09:28 PM
Don, i switched caps, i,m thinking this may be an enginevacumn/pulse problem from a leaking gasket, probably the crankcase.

I,m going to dismantle the carb again completely to check for any dirt obstructions etc, there's some very tiny holes in that carb.


Unhook the gas tank and gravity feed the carb to test.... that way you might save unnecessary crankcase work.

Don't blast the carb with air - you destroy the integral check valves.

sasquatch
06-06-2012, 09:34 PM
Re: unhook the tank, to save crankcase work:

I,ll give that a try too.

Don Young
06-06-2012, 09:56 PM
While you have the carburetor off/apart, check that the little pulse passage to the crankcase is clear and not obstructed by a gasket. Be sure its joints are all sealed by the gasket or diaphragm. Check that the little diaphragm tabs that make the check valves are not bent. If it uses one, be sure you have the gasket on the correct side of the diaphragm; I forget which way it goes but it only works one way.

sasquatch
06-06-2012, 10:00 PM
Yup, will try to do a thorough check,, i,m still puzzled as it ran SO good, perfect idle the day before, something changed over the next 24 hours.

A.K. Boomer
06-07-2012, 01:45 AM
That's the spirit --- you'll get it - it has to obey the laws of physics --- it's not some kind of voo-doo (unless an x gf made a mini u and put a curse on u - don't ask)

were all pullin for ya...

oldtiffie
06-07-2012, 03:07 AM
Not an Echo is it? Them dammed things don't need as reason not to run!

Odd that.

I was having a bit of trouble not too long ago with a quite old "Stihl" 2-stroke weed-eater which had being going very well up to that time.

My dealer suggested dropping the Stihl as it was hard to source parts for and "shop time" would be considerable. He suggest an "Echo" and it has perforfomed faultlessly - same as my "Echo" "pole (extendable)" chain saw.

I really do like the modern body harness for the "Echo" weed-eater.

I have older model "Stihl" petrol and electric chain saws which are running very well but if they need to be replaced, I'd be quite happy to change to "Echo".

sasquatch
06-07-2012, 08:48 AM
No, not an "Echo".

Just a little 18cc "Poulan Weed Eater" Manufactured by WCI, it has a "Walbro" Model 226 carb.

(There were 3 different types/brands of carbs on these things.)

Abner
06-07-2012, 09:36 AM
I understand your frustration. But I have a 30 yr old stil saw runs great(30 yrs!). The newer weed eaters like mine have some sort of carb to limit emissions or so they say. I think part of their brilliant emissions plan was to make it (not work) by restricting the fuel.

- after years of having some dope(r) at the saw shop work on mine I went back to the most simple, fundamental trouble shooting. It all comes down to spark and fuel. And your problem sounds just like mine - a lack of fuel.

Until you have cut the screen on your fuel filter you have not done it all. Running a weed eater with a hole in the filter screen makes no sense on many levels but it works and you sir - have nothing to loose.

lakeside53
06-07-2012, 12:21 PM
Cutting the fuel filter screen is a really bad idea and has nothing to do with restricting fuel flow and emissions. Rule 1 in such a motor - filter the fuel to keep the junk out. Tanks are always full of grass, dirt and other debris. Change your fuel filter every year or so. It's not just a "filter" - it is fuel pickup - it traps foaming fuel (vibration) when the tank is low.


Tiffie - what your dealer said is just a "local" aberration. Stihl in the USA has 99.8% parts availability for up to 20 years old, with about 90% of those available overnight to 3 days if it has to be shipped from another warehouse. When I worked for a Stihl Dealer, I built a 1980's BRAND NEW 056 Magnum 2 from new parts - the last of some, and I did have to call the wareouse to dig for the rare stuff, but... (don't ask the cost :) ). I still have it.

There is nothing wrong with Echo, but most brands make low-end junk as well as "pro". If you buy a $99 weed eater, don't expect long life in "robust" use.