pro v 200 HELP PLEASE (rod bolt)

[lunker0477]

have a 1994 p200tlrs pro v having problems with a mid range surge and iv lost 600 rpm , boat come up on plane fine then surges like its starving for fuel through out mid range then will only run 4800 rpm on top end used to turn 5400 to 5500 rpm ,changed and cleaned all filters ,2 new fuel pumps ,1 had a small pin hole in it, but id didnt fix problem,new lines from primer ball to carbs,carbs rebuilt by yamaha dealer to the tune of 500 dollars,still not right,he has carbs off again going through them,read in another post that thermostat malfunctioning could cause a lean condition anybody got any other ideas.thanks

 

[lunker0477]

Re: pro v 200 HELP PLEASE

Re: pro v 200 HELP PLEASE

ttt

 

[lunker0477]

Re: pro v 200 HELP PLEASE (rod bolt)

again

 

[rodbolt]

Re: pro v 200 HELP PLEASE (rod bolt)

still sounds like a fuel issue.
make sure the correct main jets were installed in the correct carb bowl, some of those motors used 3 different sizes between the banks.

 

[lunker0477]

Re: pro v 200 HELP PLEASE (rod bolt)

thanks ,will check and see keep u posted

 

[lunker0477]

Re: pro v 200 HELP PLEASE (rod bolt)

told dealer to check to see if main jets were in right bowls.he said 1 of the slow air bleed jets was messed up and might not be seated in carb causing this fuel problem this part is # 30 on the yamaha schematic what does it do.thanks

 

[rodbolt]

Re: pro v 200 HELP PLEASE (rod bolt)

pilot air jets will make it idle funny not make high speed funny.

 

[Big Keepers]

Re: pro v 200 HELP PLEASE (rod bolt)

It sounds to me like a main jet issue. Mid range to WOT would be using the largest jet in the carburetor to supply fuel. Perhaps someone didn't get the float set properly and it is starving for fuel at higher RPM but has plenty at idle.

 

[lunker0477]

Re: pro v 200 HELP PLEASE (rod bolt)

talked to yamaha dealer today ,he said all main jets were marked 154 in all 3 carbs,any other ideas.thanks

 

[rodbolt]

Re: pro v 200 HELP PLEASE (rod bolt)

does this engine use a quick connect fuel fitting at the cowl? does it have a check valve between the engine fuel filter outlet and the lower lift pump intake?
has the fuel system vacum been checked at about 70 Lph for less than 4" HG?

 

[lunker0477]

Re: pro v 200 HELP PLEASE (rod bolt)

engine does not use a quick disconnect,check valve removed and replaced with in line filter (new).not sure about fuel system vacum checked i will call marina and see ,what does lph mean and also 4''hg.sorry for so many ? but need to know how to explain to mechanic,rod bolt wish you were a little closer i would be making a road trip to n.c.lol no very many yamaha techs here in western m.d lol.thanks

 

[rodbolt]

Re: pro v 200 HELP PLEASE (rod bolt)

LPH is Liters Per Hour, to use GPH Gallons Per Hour then figgure about 20 GPH.
4"Hg is 4 inches of mercury on a vacum guage.
you either have a fuel restriction or the carbs are nasty again.
your engine doesnt use the engine temp to control fuel delivery.