Quadrajet Problem Solving > Diagnose a Quadrajet carburetor problem

Marine Quadrajet Flooding Out

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rozicrc:
I have a marine quadrajet 17083522 that I rebuilt with one of Cliff's kits as the idle circuit was plugged up.  It is on a mercruiser 3.7 liter engine, and the float was set to 3/8".  I had issue with the carb stalling out when the boat was warming up in the water, where the back end sits a little lower than the trailer, and fuel would spill out of the intake gasket to carb mounting surface to the point where I would not start it again for several hours as I was afraid of a fire.  Long story short, I have rechecked the float measurements for appropriate setting at 3/8", vacuum checked the needle and seat assembly, installed a fuel pressure regulator set at 4 psig, and today have had the same issue.  The issues seems to get worse when I park the boat on a steeper incline, in other words if I lift the bow up by parking on a steeper part of my driveway I get more fuel running down the backside of the carb.

I am starting to wonder if I could have a needle/seat leaking by, or if the listed 3/8" is not the correct float setting.  Please help!!

rozicrc@hotmail.com

StillLearning:
Try dropping the float to 1/2" or so and see if the flooding goes away. There are other reasons for flooding but this is one of the most common.

Cliff Ruggles:
3/8" is PLENTY low for a Marine unit.  You have other issues someplace.

Could be leaking at the gasket under the seat, float arm bent/dragging, or the clip on the needle is hooked incorrectly into one of the holes on the float arm, but the problem would not be float level......Cliff

rozicrc:
I actually disassembled the carb and put regulated air on one side of the carb, and filled with water to test for float operation.  The water shuts off the flow of air at 4 psi and 1/2" below the top of the bowl.  At 5.5 psi I get sputtering but increasing the water level or dropping the pressure back down seals it.  The carb is angled down 10 degrees on the boat.  Other than trying the wedge should I try and swap floats?  This is a brass unit at 9.91 grams so it is borderline for the spec of 9.88

rozicrc:
Oh and no clip on the needle it is gone per the book.

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