OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Trimmers and Brushcutters Ryobi Trimmers & Brushcutters Ryobi Lawn Hornet 1100 MK III Leaking

Hi grumpy, Ok, after some more testing and some troubles getting the cutter to start after stalling, I decided to revisit your instructions and here is what I am to so far. The position of the needle was sitting somehow 4 to 5 mm below the flat part of the carby body. I realised this wouldn't come to meet the 1.65mm you say it should be, no matter how much I fiddle with the lever. If I bent it too much i was compromising the spring mechanism. (at 90 degrees the needle would unhook or the spring would come lose. Anything less that that would not lift it enough to be at 1.65mm from the top. I assumed that perhaps my carby is different, so lifted the needle as much as i could and went ahead trying to adjust the mixture screws. The problem I have now is the cutter wouldn't start for the initial settings ( 1-1/4 turns CCW on both screws). I tried a bit more turn and a little lees turn in either or on both screws with no luck. This is just after I had been using it. One good sign is, in the choke position I get a positive response. So much that it sometimes runs on full choke for a few seconds. I'll die if I switch to partial choke. Similarly when I manage to get something out of it in the partial choke position, it is just a fast burst that dies out in no time. I have tried to switch this quickly to the run position but it dies anyway. Is it possible that my carby needs different initial L and H settings. It was running some minutes before I played with the screws. I didn't actually take note but it seems i had to screw them in more than 1-1/4 turns to get them to the bottom.

Lifting the needle makes the mixture richer. If you lift it too far, the carburetor will flood, which will be pretty obvious if it happens. However there is something wrong with the process if it measures 4 to 5 mm down, and runs as well as you had it running initially. You didn't by any chance put the lever in upside down the last time you assembled it, did you? The spring end of the lever has a feature to center the spring, if you have it the right way up.

Using different L and H settings will not hurt anything, but needing to use them tells you that your metering lever height setting is wrong. If you need to use a lot more than about 1 1/4 turns it tells you that you have the needle too low, and if you need to use a lot less it tells you that you have the needle too high.

Nope, the lever is not upside down. For my type of carburator it is just practically impossible to lift the needle that much. It sits at about 4-6 mm below the flat part of the body. So I did some more research and found a couple of sites that say the walbro tool is to measure the height of the lever arm(not the top of the needle) That makes more sense to me, at least for my type or carb and it is consistent with the photo you attached and other photos I have seen. I also found out that the tool is not needed for WT carbs as the lever sits flush with the surface right beside it. This can be set with the end of a small ruler. I will try readjusting the lever back to where it was and see. I know I am spending too much time on an old cutter that people say is not worth the money but this has been a great learning exercice, which is what I am really after.

It seems the 2 months since I last set a metering lever is too long for my memory to hold up: I gave you an incorrect instruction. Yes, you have to set the height of the lever arm directly above the spring, not the height of the tip of the needle.

Now, let's run through the process with that correction. The WA model does not require a measuring tool, for the reason you gave: you can just lay the end of a ruler across the surrounding metal and it has to just touch the end of the lever, right above the spring. However that is because the WA has a flat surface lower than the surrounding surface. Here is the instruction from the WA manual:


Here is the one from the WT manual, which you will notice applies also to the WA:


The measuring tool you made is supposed to be the same as the one in the WT manual: it spans all the way across the end of the carburetor. What you may be saying is that the dimension I gave you (1.65 mm) is incorrect.

Here is the Walbro Service Manual's instruction for setting the lever height:


So, if you use the 1.65 mm gauge you made, applying it to the lever arm above the spring, not the tip of the needle, does everything suddenly work correctly? Or are you saying I gave you the wrong dimension for the gauge? That 1.65 mm figure did not come from Walbro, it came from a repair technician on the internet, so it could perhaps be wrong - I'd very much like to find out if it is.

I found this:

Apparently there are two types of WT: Circuit Plate Type and Welch Plug Type. The first one doesn't need the tool, the second one does.




I am not sure what this all means but from the diagram above and photo below (taken from outdoorpowerinfo.com) my carb seems to be a Welch Plug Type. So it may need the tool after all.



However, there seems to be on line speculation that when you use the tool, the height of the lever arm comes to be flush with (if not very close to) the internal flat part of the carb around the lever. My carb has that flat section. I haven't yet tested this.

In regards to the distance (1.65mm), I didn't mean to imply it was wrong. In fact I found it is supposed to be between 0.060" and 0.070" You gave me 0.065" so you are spot on.

Had to edit to add this last pict showing the position of the straightedge for the WA WT WTA Welch Plug Type one.

Now that you have made the gauge, it seems like a good idea to use it - it works on any WA or WT, as I understand it. Then having set the lever correctly, you can check whether the lever height does correspond with the nearby flat surface on the carburetor body. On the WA, the flat surface does work, and that is the way I set WA lever height, but WT is not quite so straightforward because there are variants. That seems to be why Walbro recommends the tool, which works for all of them.

For future reference, remember that your tool is for WA and WT: some other models use other dimensions for the distance between the top of the lever and the height of the carburetor body.

Referring to a couple of posts ago, I think it is well worth persevering with getting this carburetor, and this trimmer, working properly. You are learning something as this goes forward. You never learn anything by giving up, you just lose confidence in yourself.