Issue getting on plane and engine turning off under load.

[Cigalert]

Now you got me thinking.

Sy ruined a few perfectly good weeks tank testing the boat and saying everything was fine. The more the throttle was hammered the worse the problem got. I finally yanked the plastic cover off the motor while underway. My buddy was driving and I pinned the throttle linkage by hand. Easy to trace from there but a real crappy rigged boat. When I say drywall screws I'm not exaggerating. 3" screws and about 1/4" of the screw was buried.

BTW, I'm interested in seeing the boat cause I was pretty loaded up in Needles when I fixed that thing....with the original screws. Might be my rigging to blame.

Sent from my hemDROID

[jetboatperformance]

Would tend to agree with Menace and others re the potential Carb issue , most commonly the accelerator pump circuit could be a problem (cough and die out) , Quadrajets were OEM Carbs in Gm products from late 60s to mid 80's and can actually work well with stock applications (I actually worked on these at Cadillac ) . The fact that this boat sat for 2 years is a complicating factor as modern fuels have a very short "shelf life" and they also tend to attract and moisture .moisture can over time gather in the low reaches of the float and accelerator pump well (inside the carb) and create white powdery corrosion which reeks havoc with carb internals Very likley you may have to clean and kit the carb as a starting point Tom

[riverrunner1984]

Sy ruined a few perfectly good weeks tank testing the boat and saying everything was fine. The more the throttle was hammered the worse the problem got. I finally yanked the plastic cover off the motor while underway. My buddy was driving and I pinned the throttle linkage by hand. Easy to trace from there but a real crappy rigged boat. When I say drywall screws I'm not exaggerating. 3" screws and about 1/4" of the screw was buried.

BTW, I'm interested in seeing the boat cause I was pretty loaded up in Needles when I fixed that thing....with the original screws. Might be my rigging to blame.

Sent from my hemDROID

Im looking for a pic through a bunch of old Disks. Ill post one when I find it.

[riverrunner1984]

Here is a pic of the boat on the trailer as well as the carb...When I pulled the carb off, I noticed some residual card board like material where the gasket would, be stuck to the engine. Any tips on removing it? Is this a bad thing???? I am new to all this so thanks for all the advice.

[Cigalert]

Interesting colors...looks awful close but they made so many purple/teal boats around that time frame. Did you peak under the drivers side and see if the carpet on the back of the front seat was worn?

And the only carbs I know about are in bread.

[riverrunner1984]

Interesting colors...looks awful close but they made so many purple/teal boats around that time frame. Did you peak under the drivers side and see if the carpet on the back of the front seat was worn?

And the only carbs I know about are in bread.

LOL at colors, it is a work in progress. The caret is not worn under the seat. However, after reading the previous comments, I went home last night and unscrewed the foot throttle and found that the front seat was stopping it maybe about 3/4 of the way now. Needless to say, I will be moving it further back....

This may explain the planing part but not the boat dying when under load in the water. Based on the looks of the old carb, I am going to purchase a new one. Thinking this will be the key.

[Cigalert]

LOL at colors, it is a work in progress. The caret is not worn under the seat. However, after reading the previous comments, I went home last night and unscrewed the foot throttle and found that the front seat was stopping it maybe about 3/4 of the way now. Needless to say, I will be moving it further back....

This may explain the planing part but not the boat dying when under load in the water. Based on the looks of the old carb, I am going to purchase a new one. Thinking this will be the key.

Nice, I know the carpet was worn on the back of the front seat and the screws holding the pedal bent because the performance gradually got worse on my buddies boat.

And probably a good call on the new carb too. My 1990 454 looks like Telly Sevalas' head compared to yours.

[jetboatperformance]

Here is a pic of the boat on the trailer as well as the carb...When I pulled the carb off, I noticed some residual card board like material where the gasket would, be stuck to the engine. Any tips on removing it? Is this a bad thing???? I am new to all this so thanks for all the advice.

Re the "residual gasket material" protect the plenum area with a shop rag and carfully scrape the gasket off the intake as well as the carb, just an observation on the carb , Marine OEM QJs are often painted Black, the top cover and base on yours is black but the float bowl/chamber/main body looks to have been "boiled out" or replaced perhaps ? , in any event of the outside condition is an indicator of the inside the carb likley needs to be cleaned and kitted , Tom

[Woods 017]

Little late, but if there is anything in the jet (ie a stick or piece of debris) the boat will struggle to get up on plane. How does the impeller look? When you hit the gas does the motor respond? Hope you have it figured it out by now but if it isn't the carb I would take quick looks inside the pump just to make sure everything is ok.