OutdoorKing Repair Forum Forums Repairs and Maintenance Questions On Hand Held Blowers/Vacuums Petrol Blowers & Vac's ECHO pb 1000 carburettor tuning

I am tryng to correct a problem where the carburettor screws have been messed around with to the point where the motor does not have ignition.

i have read the owners manual under "adjusting carburettor -general" but everything i seem to do does not work. And because im trying to start the motor it often gets flooded.

Is there an easier set of insturctions to get the carby set or is it all just a game of guess?

the manual state:
1. Turn HI and LO adjustment screws (C) and (B) clockwise until
seated lightly in carburetor body. (this is barely screwed in position i presume?)

2. Turn (B) adjustment screw counter clockwise 1-1/8 turn.

3. Start engine and allow it to run at high idle until warn (approx. 2-3 minutes).

any help?

It would help if you told us the make and model of carburetor. Essentially you usually start with both screws open about one and a quarter turns, then adjust them both with the engine running. Walbro recommend opening them one and a half turns IIRC, so you will be leaning them off throughout the adjustment process. Are you sure you have a strong, consistent spark? If you don't, you are wasting your time with the carburetor, it isn't to blame.
If you have ignition and a good spark plug, you should be able to start the engine - but there is a ritual that has to be followed with the choke. In most cases the ritual is, with the engine cold and clear of fuel (that is, not when you have already fouled everything up by pulling it over repeatedly with the choke closed) you fully close the choke and pull the starter until the engine burps - that is, runs for no more than half a second then stops. This usually takes about three pulls, but on a few engines it is more difficult. You then half-open the choke and pull again. It nearly always starts on the first or second pull on half choke. However if it has a belly full of fuel due to being pulled on full choke after it has burped, you will have little chance of starting it. You must commence the ritual with the engine clear of fuel.

Hi grumpy and Johno123, from what I can gather the carby is a Zama Model CIU-K11 P/no 125200-05061.

thanks deejay, i never would have found that information on my own.

No probs Johno, best of luck with it mate, they can be tricky little devils

ok, i have tried.....

i am 99% sure it was only the carby tuning that did the stuffup as i saw the blower working and then he played with the carby settnigs to 'tune' it and voila, a stall and no restart.

grumpy, i have ignition but i have 1 question to ask, in regards to this sentence:

"If you have ignition and a good spark plug, you should be able to start the engine - but there is a ritual that has to be followed with the choke."

If i have adjusted the carby screws (1.5 turns from full in) and gave the motior a couple of pulls, if it does not start, do i need to take off the spark plug and clear the chamber of excess fuel before i readjust the screws and attempt to start the motor again? (or can i just keep letting the screws off and giving it 1-2 pulls for every adjustment).

i really want to get this blower started again!

You need to have the engine (both crankcase and cylinder) clear of fuel when you begin, for the ritual approach to work. You can clear it by removing the spark plug and pulling it over 20 times with the throttle and choke wide open, using the rewind starter. Then install the spark plug, connect it, and apply the ritual (do make sure the ignition is on when you do this last part, of course).
Note that the engine will not start with the choke closed: it will only burp for less than half a second. Then you half-open the choke and try to really start it.
Two things to worry about: first, the plug has to be good. 2 strokes ruin their spark plugs fairly quickly, due to the plug operating at too low a temperature for proper self-cleaning except at full throttle. You should expect to replace your spark plug about every ten hours, unless your engine is rather easy to start. The main symptom of a dirty plug is hard starting, and cleaning the plug has only a marginal effect on this. The second thing to worry about is the possibility that the mixture adjustment screws have been abused. If they have ever been done up tightly, they are finished and need to be replaced. You can check this visually by removing them (one at a time - don't risk putting them back in the wrong holes) and examining the taper on their tips. Any microscopic sign of distortion means they are ruined: misshapen mixture screws do not adjust smoothly, and are likely to be incapable of successful adjustment.
Do not adjust the mixture screws on the fly while trying to start the engine. They can only be adjusted sensibly with the engine running. If it won't start by following the ritual with the mixture screws at say 1.25 turns, you are doing something wrong or there is something wrong with the machine. Any time you have pulled the cord ten times with the choke closed trying to get it to burp, don't go any further without clearing the engine of excess fuel again. It won't start once you've fouled it with fuel.
Incidentally I was once cursed with a little chainsaw that was hard to start. I even took it to a dealer, who said it was perfect and I should just cope. I gave the little saw away instead. It made the most beautiful 14,000 rpm 2 stroke sound I've ever heard once it was running, but life's too short to bother with an engine that's hard to start.

im happy to report that i have managed to get the blower started.

The difficult part came with guessing what combination of throttle setting and low speed it needed to get it going (tolerance of 1/3 of a turn with the low setting).

Once it started the adjustment process was fairly easy.

thanks for all your help grumpy, and to you deejay for supplying the carby model number!