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cncman08

Hard starting allis 720

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cncman08

I am having trouble starting my 720. I have an electric fuel pump on it and that worked great for the first couple years after that conversion. Now the last few months I have to put a little gas in one of the plug holes to get it started for the day. Once I get it going for the day it starts fine until the next day. I checked to make sure all the hose clamps on the fuel line were tight. That didn't help. I thouht maybe i was getting air in the fuel system due to lose clamps. I pulled the return line and turned the the pump on it seems to be flowing plenty of fuel. I replaced the fuel pump. I am trying to get every thing ready for mowing and don't want to deal with giving a little squirt of gas every day. I also took the carb apart and think I need a new jet. The jet was always was hard to adjust and I believe I found the cause. The threads for the needle were tapped crooked. I am hoping you guys have some ideas !

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720nut

Chris mine starts hard sometimes usally just change plugs. I would replace the valve,maybe trash in carb ? Mine refused to start in Ohio past weekend but Sunday morning started after filling filter with trash, gonna clean fuel system. just a thought

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cncman08

My filter looks good. I have clear one so I can see what is in it. The inside of the tank is also clean. I do not believe this is a problem with the plugs as after I put a squirt of gas in the plug holes it fires right up and runs fine. Thanks for the suggestions.

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cncman08

Is it possible there is a small leak in carb to manifold gasket or manifold gasket to engine ? Would that cause low vacuum and hard starting. Is there only one bolt that holds the manifold down on each side? I also noticed my fuel pump is noisy. It makes the noise of when you run of gas all the time. I don't remember it doing that when I first put an electric fuel pump on. That is why I replaced the pump. The new pump makes the same sound as the old one did.

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cncman08

That is a good idea about the choke. I will look at that this evening. Any idea where to find a jet? My local simplicity dealer want $75. For that price I am thinking about switching to the zenith 13793.

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cncman08

That is a good idea about the choke. I will look at that this evening. Any idea where to find a jet? My local simplicity dealer want $75. For that price I am thinking about switching to the zenith 13793.

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cncman08

Paul I did check the float it was right set at about 3/16" may a little less. The needle and seat looked clean and the rubber tip looked. I was thinking maybe a sticky float or needle though.

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cncman08

Over the weekend I did some tinkering on the 720. I found that the choke did not close all the way when hooked up to the cable. I removed the clip that holds the cable and pushed it to full choke and it has worked every time. Thank for the ideas. I also mowed for the first time with this machine. What a great mower. I wish I would have been using this for mowing since I brought it home.

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