red max carb

bertsmobile1

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Here something puzzling, the carb diagram hose connections show the larger diameter hose is the fuel inlet and the smaller is the return. But when you look at the fuel line replacement it shows the opposite.

The feed line to the carb s a SUCTION line and is always a thinner internal diameter with a heavy wall to prevent it collapsing.
The return line is a PRESSURE line and thus is thin walled and usually bigger.
Reversed, the carb will not prime as you are sucking air from the top of the tank & blowing bubbles out the filter.

I it is not pumping fuel through the primer there is either an air leak or one of the check valves is not working.
Fill the tank to the top of the filler neck, replace the cap & pump the bulb.
IF it now pumps fuel then you have a hole in the delivery tube, usually just near the grommet or hole where it passes through the tank.
The tubes are a service item and should be replaced from time to time in any case.

No joy with that then pull the line from the carb to the primer bulb and block it off with your finger.
When pumping the primer bulb that line must stick to you finger, if not the primer or the duck bill check vale in the primer is duff.

If you replace it under no circumstances buy a primer bulb off the web.
There are a lot out there that are defective with bulbs that quickly crack, leak or even blow apart when the equipment is running, thus coating you with hot fuel.
 

bluejeans

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Jan 1, 2015
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Thank you for all your inputs everyone. Boobala the link you sent me shows the fuel inlet is the larger diameter hose from carb diagram, but the replacement fuel line shows the larger diameter line is the return. So I ran a new tylon fuel line to the inlet (larger diameter)and shorten the smaller diameter hose. Now it works like a charm. Maybe reddmax changed their carb and fuel line set ups in the newer models from the ebz7500 model. "CHEERS!"
 

Boobala

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Feb 15, 2015
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Thank you for all your inputs everyone. Boobala the link you sent me shows the fuel inlet is the larger diameter hose from carb diagram, but the replacement fuel line shows the larger diameter line is the return. So I ran a new tylon fuel line to the inlet (larger diameter)and shorten the smaller diameter hose. Now it works like a charm. Maybe reddmax changed their carb and fuel line set ups in the newer models from the ebz7500 model. "CHEERS!"

I find it hard to imagine the diameter of the lines was the culprit, are you sure the old lines weren' clogged, cracked or whatever ?? Well no matter now, so long as you're up and running, keep the filter CLEAN !! Regards, Boobala
 
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