Aisan fuel systems are used in a variety of different forklifts including Toyota, Hyster, and Yale. Aisan is partly owned by Toyota so you see mostly Aisan in Toyota forklifts.
Rebuilding an Aisan regulator is a bit more difficult than the traditional and popular Impco model J. Depending on your skill level, you might want to simply replace the entire unit.
Remove solenoid from unit
Remove back studs with socket
Remove seals and pad
Remove parts from new Aisan repair kit
Re-install valve parts
Re-install back cover
Install o-ring and spring
Re-install pad and oring
Re-install sintered metal filter
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