Homelite string trimmer problem

[trobinson017]

I have a Homelite Trim n' Edge trimmer, 25cc, model UT20024A. Worked fine until yesterday when it stopped dead in the middle of trimming. Plenty of new fuel mix in the tank. After initial troubleshooting I drained the gas out of the tank and along with it came some tubing pieces and the fuel filter. Do'h! I got new tubing today (clear tubing!) and put it all back together, but I'm not sure if the tube lengths are correct or if they even need to be certain lengths. For that matter, I don't know what the non-filter tube does. It had nothing attached to it as far as I can tell. Carb overflow? Air input?

Anway, once it was all back together I tried to start it. I pumped the bulb once and it stayed flattened. Normally, it pops right back up so I can keep pumping it. But now it always just stays flat. Seems like this should be an easy fix and may be related to the tubes I replaced. Oh, there is fuel in the bulb and the filter tube has fuel in it. The other, uknown tube also has some fuel in it but not completely. It's like some fuel came out of the carb into it when I pushed the bulb down.

Any idea what's keeping the bulb from popping back up? Any other help on getting this baby running would be much appreciated. My yard looks like crud with only 1/2 of it edged.

Thanks!

Trob

 

[Lawnranger]

Try switching the lines at the carburetor and see if that makes a difference. The longer line in the fuel tank needs to be long enough for the filter to move around (model airplane people call them "clunks") and pull fuel from the bottom of the tank no matter the orientation of the engine. The shorter line is the return line from the carburetor and allows the primer bulb to "push" fuel back into the tank. I had one case where the primer bulb didn't return to normal and it was due to a plugged screen in the carburetor but don't go there yet, just try switching the lines at the carburetor and report back what you find.

 

[Parkmower]

Did you use actual fuel line, not just clear tubing? Was it the same diameter as the old one? Did you replace both lines?

 

[trobinson017]

Did you use actual fuel line, not just clear tubing? Was it the same diameter as the old one? Did you replace both lines?

The tubing package specifies it's a fuel line for most 2 cycle small engines. It is the same diameter as the old stuff and I did replace both lines. The tubing fits snugly over the carb input/output as well as the holes into the tank.

Trob

 

[trobinson017]

Try switching the lines at the carburetor and see if that makes a difference. The longer line in the fuel tank needs to be long enough for the filter to move around (model airplane people call them "clunks") and pull fuel from the bottom of the tank no matter the orientation of the engine. The shorter line is the return line from the carburetor and allows the primer bulb to "push" fuel back into the tank. I had one case where the primer bulb didn't return to normal and it was due to a plugged screen in the carburetor but don't go there yet, just try switching the lines at the carburetor and report back what you find.

I'll give this a try tomorrow. Since the fuel filter was disconnected when I discovered the problem I may very well have swapped the lines when I replaced everything. Thanks for the suggestion!

Trob

 

[Mini Motors]

I'd ask about the filter, and if you cleaned or replaced it. And I'll second the inquiry about fuel safe hose.

The filterless line is a return line. The primer bulb pulls fuel through the filtered line into a galley, where it can get sucked into the engine. When this galley gets full, the overflow goes back through the other line back to the fuel tank. If the filter is clogged, and the lines are reversed, the primer bulb will do what you described. And if your fuel line was broken just above the filter, you wouldn't have known if it was clogged. A bit convoluted theory, but if true, could answer your issue.

 

[tyjoja]

just had a poulan pro weed eater apart and it has two lines, 1 to carb, 1 to bulb and then to carb. the guy above may be right and you have them reversed

 

[trobinson017]

UPDATE: Ok, I went and found a tune-up kit specifically for my model of trimmer. It comes with new primer bulb, fuel line with filter attached, return line, a special tool for line insertion into tank and instructions. According to the instructions I have the lines in their correct positions. That's beside the point tho and I've replaced them with the ones from the kit. I also replaced the bulb. Everything as regards the fuel system from tank to bulb is new and installed according to the instructions. I filled the tank with gas mix and pushed the primer bulb. It came right back up the first push. Second push it hesitated but came back up. Third push it stayed flat. Very little gas came into the bulb. The fuel filter line was full of gas. A little bit of gas got into the return line.

I wonder now if the base unit that the primer bulb sits on top of, which looks to have a diaphram in it, is the problem. Perhaps the fuel intake into that is plugged or there's debris inside that unit? That's all I can think of at this point. It just seems air is not entering or exiting the bulb properly.

Any other ideas?

Trob