Mercury XR6 150 has issues at WOT

[Hookin_Hogs]

Hello, I have a 1998 Mercury XR6 150hp that is carb. The issue I have is one, kinda hard start when cold but I realize that is to be expected. My main problem is that when I go WOT (hot foot) it acts like it’s either getting not enough or way to much fuel. Starts bogging and if I ease into it it’ll eventually pick up at sit at 5200rpm full throttle no problem. After it reaches Full throttle, when I left off and push the pedal down again it’s snappy and works great, no issues. So far I have replaced fuel filter, had carbs rebuilt and synced and linked, rebuilt the fuel pump, put new gas in tank. So it still has the issue and I brought it to my mechanic and he said my timing and throttle was off. He fixed both of those issues and it worked perfect! Like a dream. But yesterday I rode around in a lot of rough water and about mid day it has the same issue again, turns out I cracked my fuel filter. So I replaced it this morning took it to the lake and has the same issue again. I’m confused why sometimes it’s perfect and then sometimes it’s a pain in the a$$. I’m probably forgetting something but I will answer any questions that are needed. Thanks I’m advance.

 

[racerone]

There is no reason for it to be hard to start when cold------Post your procedure for starting it cold.----Perhaps missing a step.-----Test run with another fuel tank and hose.