Cliff's Quadrajet Parts and Rebuild Kits

Quadrajet Problem Solving => Dialing in your rebuilt Quadrajet carburetor => Topic started by: trudaddy on August 07, 2025, 09:11:32 AM

Title: Excessive Fuel Burn Black Exhaust
Post by: trudaddy on August 07, 2025, 09:11:32 AM
I recently rebuilt my quadrajet and did the initial 2.5 turn tune. I put on muffs. Boat fires up with two pumps and idles around 800 rpm.

Additional work done just in case relevant. I emptied fuel tank, new fuel/water filter, replaced fuel guage sender and all fuel related hoses. Replaced throttle control cables and shift linkages. All set to spec.

There is excessive fuel smell when running in addition to blackish smoke from exhaust. I got a bit of dieseling one time after running 3/4 throttle and and abrupt shutdown. I cannot figure out the issue. I have checked the float with guidance from Cliff. That is not the issue. Not sure what to check/adjust.
Title: Re: Excessive Fuel Burn Black Exhaust
Post by: 77cruiser on August 07, 2025, 09:25:01 AM
Is the issue only at idle?
Title: Re: Excessive Fuel Burn Black Exhaust
Post by: trudaddy on August 07, 2025, 01:02:55 PM
If I start the motor and it just idles it is mostly fine. The problem happens when giving it gas and generally driving the boat as intended. The problem persists when running in gear at low speeds in no wake too. At idle after first starting up it isn't really an issue.