Fuel Delivery Issues
#1
Thread Starter
Platinum Member
Joined: Sep 2012
Posts: 57
Likes: 1
From: Georgia
I recently purchased a 38' Fountain with blown 540's making 750-ish ponies. The port motor runs flawlessly. The starboard motor has been "popping" and making mischief. The "popping" follows a spike, then a drop in fuel pressure in the gauge for that motor. The backstory is this: purchased the boat out of state (did successful water test, no issues with motors, clean bill of health) and put it on a trailer making the 9.5 hr drive back home. The following day fueled up boat and then went to the lake, popping sound when you pass 2750-3000 rpm's (starboard motor only). The motor is a 540, Teague superchiller, B&M blower, 575sci dual throttle bodies on top all tuned by Tyler Crockett by previous owner. The starboard motor has a new Edlebrock 1790 fuel pump (replacing a weak SX Performance 18203), new Aeromotive regulator (and matched to previous regulator's output pressure) and a fresh/clean Pureolator fuel filter. The fuel pressure at 2500 is 30-32psi (on one of the 2 rails after the regulator) and holds constant at idle. In fact, the motor idles without issues what-so-ever. The fuel pressure (while slowly advancing throttles to get on plane) stays constant until the 2500-2700rpm range, then it spikes to 35-37, dips down to 24-25, the motor pops due to lean fuel conditions, and I immediately pull off the power. I know I am missing something simple because I have been staring at the problem from a close range. Input/help is appreciated. Please feel free to ask questions.
#3
Registered
Joined: Aug 2007
Posts: 1,038
Likes: 2
From: St.Louis MO
Check the dip tubes in the tanks. You might have a pin hole or pick up tube issues. I had a issue with my Baja, that there were screens on the bottom of my pick up tubes and they were clogged up. Took them out..took out the screens...




