260 help help help bogging problem

[tangerine386]

ok guys i need help i have a 93 260 osr 7750 rev limit problem is when i put the boat in it runs good for a while then it sputters and dies it will crank back up idle fine but when you try to give it gas it bogs down wont plane this has happen 3 times now compression is good this is alist of new parts fuel tank removed cleaned,all lines replaced new filters ,injecters pulled cleaned flowed,new 984fuel pump,new 39lb regulator 55lbs of pressure at the rail,new stator,2 new switch boxes and replaced the ecu temp never above 140 while running coils are firing im about to go bald pullin my hair out on this one ive got near 4k in this thing now help help also the horn was removed down to reeds and cleaned and all lines were replaced https://youtu.be/gTakC0oK2JI or just look up my channel seattime or punch in the bogging problem

[laser_ED]

ok guys i need help i have a 93 260 osr 7750 rev limit problem is when i put the boat in it runs good for a while then it sputters and dies it will crank back up idle fine but when you try to give it gas it bogs down wont plane this has happen 3 times now compression is good this is alist of new parts fuel tank removed cleaned,all lines replaced new filters ,injecters pulled cleaned flowed,new 984fuel pump,new 39lb regulator 55lbs of pressure at the rail,new stator,2 new switch boxes and replaced the ecu temp never above 140 while running coils are firing im about to go bald pullin my hair out on this one ive got near 4k in this thing now help help also the horn was removed down to reeds and cleaned and all lines were replaced https://youtu.be/gTakC0oK2JI or just look up my channel seattime or punch in the bogging problem

if that is a gold regulator with 55lbs fuel pressure ,,,,start there,,,,it should be 39lbs,,,black reg is 56lbs,,,,,what chip are you using ..48,,,,63????

[capteliminator]

Did you check the fitting in the horn that feeds the map sensor in ECU for blockage when changing ECU's?

[tangerine386]

my fuel pressure gauge is right before rail that is steady at 55lbs the reg is 39 lb and new all hoses new i will recheck those and it is a A17 ecu it did same thing with old ecu

[tangerine386]

Any one any one crickets!!!!

[BUZZIN' DOZEN]

The regulator is what determines pressure, when working properly the only way to make more, any where in the system with a normally functioning regulator, is to dead head the return line.
Yes, sounds like you need to look into your regulator.

[ShadowFlier]

A17 on a 260?

That box is for a promax

[tangerine386]

yes the a17 was on it i just purchased another a17 it a LL block the regulater is new but it is a cheaper model than the bosch so maybe that a issue but why would it run fine for 15-30 min then act up could i have a temp sensor going bad causing the ecu to go into safe mode only idle

[tangerine386]

according to parts diagram 93 motors came with a15 or a17 ecu

[2015Duramax]

if you have 55psi on the fuel rail your regulator is not working or have a blockage in the return line . If your box is set for 39psi and you have 55 psi at the injectors it will give you problems .

[tangerine386]

just to clarify my fuel pressure gauge is mounted after the fuel filter right before the rail just outside of the cowling showing the pressure at 55lbs before the regulator and my return line is flowing good can hear the fuel going back in tank when fuel pump on and motor not running so that part is good

[ShadowFlier]

just to clarify my fuel pressure gauge is mounted after the fuel filter right before the rail just outside of the cowling showing the pressure at 55lbs before the regulator and my return line is flowing good can hear the fuel going back in tank when fuel pump on and motor not running so that part is good

Yes but if your pressure at the rail/backside of injectors is 55lbs and it’s supposed to be 39lbs it can give you issues.

[tangerine386]

why would it run fine for awhile then act up if reg not working then wouldnt just not work from get go? my link to video is not right will try to repost it any way in youtube search window type the bogging problem it should pop up

[tangerine386]

search window on youtube the bogging problem for a video of it acting up this was after running up river for 6-8 miles

[CI STV]

just to clarify my fuel pressure gauge is mounted after the fuel filter right before the rail just outside of the cowling showing the pressure at 55lbs before the regulator and my return line is flowing good can hear the fuel going back in tank when fuel pump on and motor not running so that part is good

It doesn’t matter where your regulator is mounted, as long as it not on the return side of the regulator. If you’re seeing 55 psi anywhere on the injector side of the regulator (which is where you’re saying it’s at) and the ECU is calibrated for 39 psi, the motor is going to run pig rich and load up. Do you have the Gold or Black regulator? The gold is the 39psi and black is 56psi. If you have the Gold regulator and you actually have 55 psi of rail pressure, then something is wrong. Even if you hear fuel returning to the tank, the return could be restricted somehow sufficiently to increase fuel pressure. You can bend/kink or pinch the return line to increase pressure significantly with a return fuel system. That’s why they always recommend a return that’s the same size as the supply.