# Trimmer spewing gas.



## Fusion7 (May 18, 2009)

Hello all. I need some help with a Homelite UT20860 weed trimmer. A friend gave me this trimmer because it wouldnt run right so I put all new gaskets on it, new fuel lines and filter, new spark plug and cleaned the spark arrestor screen/muffler. Now it will runs fine for 5 minutes or so and then dies and about 20 seconds after it dies gas starts spewing out of the carb through the air filter. It will do this for a minute or two then quits. This trimmer has 2fuel lines and I tried to keep track of which went where but I am not positive I got them back right. Any ideas I what I screwed up? Thanks for any help.


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## geogrubb (Jul 28, 2006)

Sounds like the duckbill valve in the fuel cap isn't working properly, I think they are supposed to let air in and out but not the fuel, try removing the fuel cap to release the pressure when you shut it off to see if helps. Have a good one. Geo


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## rotti1968 (Apr 26, 2009)

I would also check to make sure your needle is closing,it may be stuck in the open position. you may have other internal carburetor issues that will do this.


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## Guest (May 18, 2009)

if your not 100% positive that you put the lines back on correctly, try switching them around and see what happens.


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## Fusion7 (May 18, 2009)

Sorry for the long time in between reporting back. I finally had the time to work on this thing. What I found is that it has a Zama C1U H39 7ZB (no idea what the 7ZB is for) carb on it and going by the rebuild kit I have and searching other places (Zama's site) is that it has a Welch plug. Going by the picture and info on their site I know where it goes but don't understand what it does. There are no holes in the channel that the plug covers. When I took it apart to replace the gaskets I did not see the Welch plug. The reason why I did not think about the plug is that I had left it in the bag and dug through my trash can today and there it was still in the bag. Would installing it help my problem? I know it takes a special tool to seat it right, which I dont have. But I do have all the tools to fabricate one.


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## Lawnmowertech (Nov 12, 2008)

Fusion7 said:


> Sorry for the long time in between reporting back. I finally had the time to work on this thing. What I found is that it has a Zama C1U H39 7ZB (no idea what the 7ZB is for) carb on it and going by the rebuild kit I have and searching other places (Zama's site) is that it has a Welch plug. Going by the picture and info on their site I know where it goes but don't understand what it does. There are no holes in the channel that the plug covers. When I took it apart to replace the gaskets I did not see the Welch plug. The reason why I did not think about the plug is that I had left it in the bag and dug through my trash can today and there it was still in the bag. Would installing it help my problem? I know it takes a special tool to seat it right, which I dont have. But I do have all the tools to fabricate one.


yes the welch plug can play a huge roll in the way that carb operates


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## 30yearTech (Sep 14, 2006)

All you need to install a welch plug is a flat punch and a hammer. Nothing real special about it. Just don't hammer too hard...


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## Fusion7 (May 18, 2009)

Well, from what I have read thats what I figured I could do, but wanted a pro to tell me so. I have read that some cover the thing with clear fingernail polish or other products to seal the plug. Do this or not? Now, what exactly does this thing do? All I can gather is that it would keep the metering lever from raising the needle too far. Like I stated earlier there is no holes in the slot the plug covers and looking at some of their other carbs they have check valves and retainers. There is no room for this that I can see.


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## Fusion7 (May 18, 2009)

Back again. I called Zama since they are in my home state about the welch plug and the guy said its in there if I look closely. The one in the rebuild kit will not fit where the old one is I dont care what the guy says. He said the needle is sticking open causing the trimmer to spew gas, rotti1968 nailed it. I checked it and, checking the spring the rubber tip on the needle, the brass orifice the needle plugs..they all seemed fine to me. Put it back together and it is still doing the same thing. After $50 of parts I gave up on it. My father-in-law gave me an IDC580 that ran fine when he put it up a few years ago. Im going to try and get it running this week, if I can. Man that thing feels heavy-duty compared to that Homelite. Money is tight or I would go buy a new trimmer. Thanks for your help.


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