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66 Fuel Pump Leaking

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Old Mar 7, 2020 | 06:16 PM
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66 Fuel Pump Leaking

Y'all help. There's a hole in the fuel pump on both sides next to where the mounting bolts go. Didn't pay much attention to it when I took it off and redid the gasket, but now I've got fuel pouring out of there and I can't for the life of me figure out why that hole is there in the first place. Is there supposed to be a plug? Is that supposed to act as an overflow valve type thing? Losing a lot of fuel when it's running.
 
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Old Mar 7, 2020 | 06:42 PM
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So apparently it's a weep hole and since there's fuel leaking out of it, the diaphragm has torn and I either need to replace that somehow or buy a new pump. Probably why my idle was so rough lately.
 
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Old Mar 8, 2020 | 07:40 AM
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Yep, answered your own question..
 
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Old Mar 8, 2020 | 05:07 PM
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Might this keep fuel from going into the crank if the diaphragm goes bad?
 
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Old Mar 8, 2020 | 05:20 PM
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Can't hurt. Might help. Maybe not the way to bet - take a whiff of the dipstick, does it smell like fuel, does the oil look thinned out, or reading high as if somebody added 2 quarts above the full line?
 
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Old Mar 8, 2020 | 05:51 PM
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That hole is there to keep pressure from building on the back of the diaphragm. Your diaphragm is toast.
 
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Old Mar 9, 2020 | 12:25 PM
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good news is, I just replaced mine. couple bucks and a 20 min fix.
 
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Old Mar 9, 2020 | 07:30 PM
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Ended up being no big deal, 30 bucks and 20 minutes like you said. And now I have a better idea how mechanical fuel pumps work.
 
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