'96 TBV Issue?

[Hbcraft]

1995 7.4. Owned boat for years and fixed, maintained, replaced everything at least once...except this: running boat as usual this weekend and after one of many previously successfully throttle pushes towards 4500rpms, the motor sounds like a rev limiter kicked in at 3800rpms. It won't go over 4000rpms but cuts out like crazy until I pull back below 3800rpms. It runs and idles perfectly below 3800rpms. Just did this and it is maintaining this profile since the weekend. Any experience out there with this type of temper tantrum? Until I get this figured out I'm stuck at 40mph! Lol

 

[alldodge]

Your running out of gas at higher rpm. Check for a fuel line restriction like the antisiphon valve on top the tank, and fuel pressure (4-7 psi) at the carb.

 

[Hbcraft]

Thanks AllDodge. With that confidence I'll focus on fuel delivery. Is it safe to say then that if the TBV module goes bad, it goes bad and doesn't work at all? In other words, it wouldn't just malfunction on high rpm spark advance, right? Just curious. Thanks again.

 

[Bondo]

right? Just curious.

Ayuh,.... Welcome Aboard,.... 'bout 100:1 odds,...

 

[Hbcraft]

It was the antisiphon valve. It had corrosion builtup on the backside of the check ball and couldn't open up all the way. Thanks for the help with this!