Crucial 5ive B

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1Coopgt said:
That would be my assumption. You shouldn't have a vacuum in the tank . That wont let the fuel get to the carb. The little breather vent of your should let air into the tank .
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I still don't understand then. If the tank cant vent out how is there not supposed to be vacuum in the tank? If air cant escape out the tank, then the tank would be sealed, correct?

Same issues. Hope its the isolator gasket, cause after that I don't know. Here's a video.
 
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There should be minimal vaccum in the tank when running. Like next to none if the vent is working properly. If it's got pressure in the tank something is causing it what is the question. You don't have quick connects in the fuel line, or inline filter do you?
 
Seandonato73 said:
There should be minimal vaccum in the tank when running. Like next to none if the vent is working properly. If it's got pressure in the tank something is causing it what is the question. You don't have quick connects in the fuel line, or inline filter do you?
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Yup, quick connects. Think they are the culprit? I was going to take them off and see if it ran better also. They were next on my list until the isolator gasket showed up.
 
The air vent is a o-way vent ,it allows the built up pressure to escape .if the vent gets dirty or plugged up ,your engine rpm's
will drop an eventually die!

The gas builds up the pressure alone ,just like a red gas can sitting ,built up pressure can also force an put pressure on
the carbs diaphragms ,an in time distort them ,an in some cases when the stuff sits at long periods of time ,the fuel
will push through an fill up in the block!
 
cbaker65 said:
The air vent is a o-way vent ,it allows the built up pressure to escape .if the vent gets dirty or plugged up ,your engine rpm's
will drop an eventually die!

The gas builds up the pressure alone ,just like a red gas can sitting ,built up pressure can also force an put pressure on
the carbs diaphragms ,an in time distort them ,an in some cases when the stuff sits at long periods of time ,the fuel
will push through an fill up in the block!
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"O-way"?? What's that?
 
crucialRC said:
"O-way"?? What's that?
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The fuel tank vents ,most are in the fuel cap ,but some tanks have a different type of venting device ,it is a one way rubber valve.

I think Z had installed one on his tank ,they are mostly common on weed eaters & leaf blowers!
 
cbaker65 said:
The fuel tank vents ,most are in the fuel cap ,but some tanks have a different type of venting device ,it is a one way rubber valve.

I think Z had installed one on his tank ,they are mostly common on weed eaters & leaf blowers!
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+1 one way??
don't make your mind up before you replace gaskets and new manifold ??
crucialRC said:
I still don't understand then. If the tank cant vent out how is there not supposed to be vacuum in the tank? If air cant escape out the tank, then the tank would be sealed, correct?

Same issues. Hope its the isolator gasket, cause after that I don't know. Here's a video.
Click to expand...
 
dougstar said:
+1 one way??
don't make your mind up before you replace gaskets and new manifold ??
Click to expand...
Doug, maybe I'm reading this wrong but Cbaker is saying the tank should vent out? How is that possible with our breather setup?? You said yourself the the breather we have only let's air in. Are you saying we have another vent that let's air out???
 
crucialRC said:
Doug, maybe I'm reading this wrong but Cbaker is saying the tank should vent out? How is that possible with our breather setup?? You said yourself the the breather we have only let's air in. Are you saying we have another vent that let's air out???
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LOL....it really doesn't matter which way ,as long as the tank can breath ,if it cant breath ,the engine wont run or it will run
crappy!
The easy way to find out if it isnt breathing ,is to fire up the engine ,if the engine starts to lose rpm's ,un screw the gas
cap ,if the engine starts to smooth out when you do ,then it is a pressure issue....:cool:
 
cbaker65 said:
LOL....it really doesn't matter which way ,as long as the tank can breath ,if it cant breath ,the engine wont run or it will run
crappy!
The easy way to find out if it isnt breathing ,is to fire up the engine ,if the engine starts to lose rpm's ,un screw the gas
cap ,if the engine starts to smooth out when you do ,then it is a pressure issue....:cool:
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Gotcha. I'm going to change the isolator and gasket and see what happens. I'll keep y'all posted.?
 
But ,his carb. ,the only time I ever seen that type of issue ,is either a air leak in the line or carb gasket not sealing around
the bulb ,or he has his fuel line backwards ,an his is running an drawing fuel through the other tube ,explains why his
primer bulb is not filling up with gas!
 
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