engine goes faster wile...

Weird problem i'm having cant figure this out.
1990 4.3L TB 4, ALPHA 1 4 Barrel carb.

while in WOT boat is a bit lazy, it will get on plane but not as fast. Now imagine tilt / trim is ALL THE WAY DOWN if i push tilt up or down or trim up or down as soon as that hyraulic pump kicks in the boat takes off, its like instant turbo boost, if i let go of the switch its back to lazy mode again.

whats been done : plugs, wires, cap + rotor, ign coil, fuel pump, filter, gas tank drained and cleaned, new edelbrock 1409 4 barrel carb, oil change, impeller, 14.5 x 19 prop, oh and a new battery.

any suggestions and or help would be appreciated
thanks

That doesn’t make sense unless something in trim is shorting out 12 v supply to ignition.

disconnect 12 v supply to trim when you get it out in deep water and try it out

you mentioned new 1409 carb, did you rejet this for the 4.3 as the carbs out of the box are more set up for 5.0/5.7

Ayuh,...... Sounds like a Bad Ground to me,.....

Start at the battery, 'n clean to shiny metal Clean, all the wire connections,..... Both ends of all the Grounds, especially,.....

the tilt / trim was working intermittently so i had completely rewired it. looks like i'll have to trace more wires lol

bondo said:

Ayuh,...... Sounds like a Bad Ground to me,.....

Start at the battery, 'n clean to shiny metal Clean, all the wire connections,..... Both ends of all the Grounds, especially,.....

Click to expand...

this is one of the very first things i had done.

Check... ground cable from battery to engine block.
ground (and power) leads on the ignition system on the engine block itself
where does the lift/trim system get its ground from?

Do you own/know how to use a multimeter?

sandkicker said:

Check... ground cable from battery to engine block.
ground (and power) leads on the ignition system on the engine block itself
where does the lift/trim system get its ground from?

Do you own/know how to use a multimeter?

Click to expand...

all grounds have been SUPER DUPER cleaned, and checked from end to end for any possible chaffing, rubbing etc.. all power connections also cleaned and checked end to end at : battery, solenoids, starter, alternator
Tilt / trim ground : looks like 1 ground wire from battery is going to the hydraulic motor bracket then from that bracket to the solenoid.
Yes i own and know how to use a multimeter.

snip.