Ezgo MPT 1200 acts like it is running out of fuel

[popeyeracing1]

I have a MPT 1200 I am working on for a friend. When he brought it to me it had old fuel. He also brought a new China carburetor. We cleaned tank out and installed carb. He also brought two spark plug took old ones out and installed new ones which was same number. Cart cranked up and ran good on jack. Started putting intake tube on and now it acts like it is running out of gas. Took intake tube off runs better. He pulled plugs out while I was taking intake pipe off and they are both very black. The gap on one of the plugs was closed all the way down. It doesn’t appear that anything hit it so I am not real sure. Put a new plug in it and ran it again with intake pipe off and it runs pretty good. Put intake pipe back on and it acts like it is running out of fuel. Was wondering if it was a adjustment on carb. Any help would be appreciated!!

[JPonLKN]

A few things to look at first...make sure the plugs have a gap of 0.028. Did you replace the air filter? Black plugs would indicate incomplete burn of fuel, so either too much fuel/not enough air, poor atomization of the fuel/air mixture (ie: junk carb), or inadequate spark, or some combination thereof. If you didn't take the carb bowl off, you should. I know its new, but you probably used the old fuel lines/filter and got a bunch of junk in there. If the tank had old yucky gas in it, so did the fuel lines/fuel filter. Replace the fuel filter, and clean the fuel lines out with carb spray and compressed air. Did you replace the air filter? Sounds like not enough air, so clogged air filter could be the cause. You might be better off taking the original carb and cleaning it up real good. Just my $0.02

[popeyeracing1]

I replace fuel lines. Replaced air filter. Only thing I didn’t replace was fuel pump but I pumped gas through it into a bottle and it seems to be pumping fine. I will pull bowl and check it tomorrow and I will check gap on plugs.