They won't open up unless the engine is under load. You won't be able to get the vacuum low enough without doing some damage to your engine. If you are suspecting that they aren't opening, you will need to do an on the water test with the engine cover open or off to see.
Two Chrome 10 hole wheels with Kenda Loadstar radials.
Mounted, balanced and delivered.
PM or email me for tire, wheel or package pricing.
CARBURETOR REBUILDING - $199
Parts, labor and return shipping included
Holley Marine 4160 Freshly Rebuilt $349 - Delivered
2 LED 6" BRAKE LIGHTS DELIVERED $32