I ended up replacing the Throttle lever on my echo. Since I did that last weekend, my weedeater isn't throttling as high. Basically, the throttle cable seems to have stretched and the new lever won't pull it as far. Is there a way to tighten the cable up, or make an adjustment so it throttles like it used to? Thanks
(1) All throttle cables stretch, at least a bit, (2) all tools are not constructed to the exact same dimensions -- and thus even in a newly constructed tool, the throttle cable, when it is installed at the factory (if that is where it is installed), needs to be adjusted then, and likely needs to be adjusted later -- so I think there must be a provision for adjusting the throttle cable. Usually you adjust so that when the throttle plate is fully closed, there is a little play in the cable before the throttle operating lever starts opening the throttle plate. But I seem to recall other ways of adjusting the throttle cable on various devices. Like adjusting it to not fully open the throttle plate, when the lever is fully depressed (so that the cable doesn't continue to pull on the throttle plate, beyond the point where it is full open). But my memory is not so good on this. There is usually a cable clamp near where the cable connects to the throttle plate. You can usually pull the cable cover further along, or less along, in the clamp. There is usually also an adjustment at the throttle operating lever, for where on the actual cable, the inner cable connects to the throttle lever.
Note, adjusting the outer cover of the throttle cable, further along or less along in the clamp, is usually sufficient to adjust the cable. You adjust it so that there is little play in the throttle lever, before the throttle starts opening. However throttle cables that also operate off-run switches, may be a little more complicated to adjust. It doesn't matter how much the cable has stretched, as long as it isn't stretching significantly when you pull on it, adjusting as I described above, should also adjust it so that when the lever is fully depressed, the throttle plate is fully open.
If the throttle cable operates an on-off switch, you not only have to adjust the play in the throttle lever, before it opens the throttle, but you also have to make sure that when the throttle lever is fully closed, that the switch is closed. The switch usually shorts out the ignition primary, to shut off the engine, that is why you want it closed, not open, to stop the engine, tho I suppose it is possible that there may also be designs where the switch is open to stop the engine, and closed to allow it to run. Just make sure the switch is fully operational, closed or open, whichever it is supposed to be. You may have to add a little more play in order to make sure the switch works.
i dont use echos any more but worked on lots of them in the past . the older model 2000 and 2400 mounted the cable to the engine body by using 2 brass nuts to hold the cable against a peice of plastic mount. these nuts can be turned one way to lenghten the cable and another to shorten the cable. adjust till you get more top speed. you need 2 10mm open end wrentches
"adjust till you get more top speed." I have an Echo 2000 and I see the 2 nuts that lawnboy dan is talking about. I think this is the only adjustment for the cable. I don't think there is another adjust ment at the trigger end. The length of the cable really does not matter, if it is a .25 inches too short or too long, it makes no difference. It is the positon of the cable housing, in the clamp that these 2 nuts adjusts the cable housing within, that matters. I do NOT think you should be adjusting the throttle cable using top speed as what you look at. That could cause problems with idle speed. You could easily get things so that the throttle never closes enough at idle speed, and then it will be impossible to adjust the idle properly, with the idle adjustment screw. You must adjust the cable by watching the throttle fully close, and then loosening the cable a bit more, so that you pull the throttle trigger about 1/8 inch, before you see the throttle plate cam move at all. You might even want to turn the idle adjustment speed screw all the way out, before adjusting the cable, making sure there is play in the cable. Then turn the idle speed screw back in, to adjust the idle to the correct speed. Preferabley with a tachometer, but you could eyeball it by the way the centrifugal clutch stops the trimmer head from turning -- it stops it from turning at a bit above idle speed, if it is working correctly -- so you adj the idle speed until the head stops turning, and then lower it still a bit more. So if you adjust the play at closed throttle, then the max throttle posit should automatically be correct. That is because the throttle cam, and the trigger, both move a fixed distance, which is non adjustable. The throttle cam will hit the carb stop plate, just about when the throttle trigger is all the way down. If the cable, and the trigger, does not have way way too much play in at at idle, then the throttle will open all the way, at, or before, the trigger is fully depressed. You could check to see that the throttle cam is hitting the carb stop. If it is, the is no point in adjusting the nuts to shorten pull the cable housing up further. The throttle simply won't open any more. Also, if the cable is too tight, and the throttle cam hits the carb stop plate before the throttle trigger is fully depressed or nearly fully depressed, it could make things so that during use, the throttle trigger eventually becomes damaged, and also the cable stretches faster over the months, than it should.
If you turn the idle speed screw out, then adjust the cable for 1/8 inch play at the trigger, then adjust the idle speed, you should re-check the cable, and make sure there is still 1/8 play (or a hair more). If adjusting the idle speed screw made the play a lot more, you should tighten up the play down to 1/8 inch again. I doubt this will happen tho. The idle speed screw only appears to move the throttle plate a tiny amount.
this is the only adjustment for cable length on echos. at least the ones i am familure with. true idle speed may be affected after adjustment but the idel speed screw has enough adjustment to cover this. the tric is to only move the adjustment nuts just enough that the trottles goes to wide open. if you only go this far and no further -idel speed will still be with in adjustment range of the idle screw. its desighned to work this way.
I think you are right. I don't know what I was thinking. If you adjust the nuts so that the throttle goes to wide open, and no further, or perhaps, just a hair short of wide open, the idle speed will be within the adjustment range of the idle screw. And after you adjust the idle screw, you will have your 1/8 inch of play at the throttle trigger. And it IS designed this way. I don't know what I was thinking. The reason I say to adjust the cable just a hair short of fully moving the throttle cam against the stop is that if you adjust right up to the stop, you might be erring on actually adjusting it to pull the cable hard against the stop, and the user's finger, with the trigger fully depressed, could be putting more tension on the cable than the throttle return spring would put on it, causing it to stretch faster. Also there is some risk of the user being able to break the trigger. Does echo make service information available, for stuff like this? I know these engines are really really simple, and self evident.
