[zzyzzx]

Originally Posted by MMGT1

clear tube, about a foot long is all you really need to quickly test a regulator. Pull the vac line off the regulator, put the clear tube on the regulator and then suck on the tube creating vacuum. If fuel comes up into the tube the diaphram is ruptured.
To really get serious about testing it you need a vac tester. Attach the vac tester to the regulator, pull it down to about 15g/mercury and it should hold vac for the better part of 10mins. If it falls off quickly then replacment is required.

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