150hp Black Max issues

[ChrisD2725]

Going to help my dad with his boat this weekend and want some input from you guys.

its an older ranger with a 150hp black max, probably an xr2. Anyway, he got it back from the shop after having the water pump and carbs done and it ran great the first outing. Now however when you try to accelerate during hole shot it falls on its face, if you roll off the throttle and slowly open it again it will fight through it and it runs great wants the rpm comes up. According to my dad it idles fine and starts right up hot or cold.

deductive reasoning says its going rich or lean during acceleration, i havent seen the problem first hand so im guessing carb float levels are wrong after being set by an inexperienced tech.

I dont have a book for this motor, can someone tell me what the float levels should be or offer any other advice?

 

[racerone]

Serial # is ??-----If it has low speed mixture screws then open them up 1/4 turn at a time and test run.----Not likely a float problem.

 

[ChrisD2725]

Ill get the SN's off of it, where will i find the low speed screws on these carbs? Any way to hook vaccum gauges to them to check sync? I am used to the kehins on my 1965 900, ive never messed with a black max before.

 

[Dukedog]

probably gonna be fuel delivery related.. no adjustment with those carbs.. try enrichner when it acts up.. if it helps, would "kit/rebuild" fuel pump first.. if that doesn't help would clean carbs makin' sure ta use all new gaskets (inside and out) goin' back together.. floats should "hang level" when bowl is held upside down.. approx. 1/16/3/16"".....

 

[Dukedog]

sorry I messed up.. if tha enrichner helps that leans towards, but not always carbs.. no change leans towards fuel pump.. both pump and carb stuff is cheap to not do 'em both anyway….