Re: Marine Carb or Not
 

The fuel curve, and metering circuitry needs to be set up differently for a carburetor with or without "J" Vent Tubes.

When I worked in the marine industry we had a boat catch on fire in the yard, and insurance would not cover it because some of the items on the engine were not USCG legal, even though that had nothing to do with the reason for fire.

For the slight difference in price, and performance why you you want to risk it?

Re: Marine Carb or Not
 

J tubes ...no J tubes :confused: :confused: The 330/454 415/502 356/454 all with Quadrajets don't have J tubes from Merc :eek: .

Re: Marine Carb or Not
 

As far as I know they don't have to mention that. Your automotive policy doesn't state that ANY & ALL replacement parts must be D.O.T. approved, but trust me if they are not they won't pay, and it's still against the law.

Re: Marine Carb or Not
 

I believe the vent tubs are cut at an angle so they will still pour down the carb throat.
Gary

Re: Marine Carb or Not
 

Whether or not your carb is marine spec will be a mute point when your boat catches fire from the engine compartment. Years ago my 750 holley melted and disapeared down into the intake manifold - Don't think an insurance adjuster would have been able to tell what kind of carb it was - cause it was gone! - Same with alumn valve covers and exhaust manifolds. -- fiberglass burns pretty damn hot.

Re: Marine Carb or Not
 

Holley has angle cut vent tubes also :( . Lookin at those Quads. if the gas came out the vents , your guess is as good as mine which why the gas would go. depends which way the boat was rocking , I guess :rolleyes:
The 350 Mags with the Webber carb that looks like the old Carter AFB is the same way too :eek: . So what make them ok :confused: :confused: :confused: