2004-2009 Honda TRX450R/TRX450ER Service Manual, Page 126Get this manual
FUEL SYSTEM ('04'05) Remove the pump cover, spring and diaphragmVisually inspect the following:diaphragm for deterioration or pin holesspring for damagediaphragm shaft for excessive wear or damageorifice in the cover for clogging or restriction DIAPHRAGM
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