help bennett trim tabs

when i operate my trim tabs my volt meter goes way down and my motor backkfires thru my carb. what could this be and what could i check oh bt the wak on 1986 wellcraft 230 aft cabin w/ 350 omc w/ omc cobra outdive if that matters

 

I would guess the trim tabs electrical power is likely coming through the engine harness. If it has always been that way and worked well previously then you have a bad connection developing somewhere along the line. When you attempt to operate the tabs not enough juice is coming through so by operating them you are in affect grounding out the engines ignition shutting it down.

 

Had similar on 230 omc,it was the main earth wire connection corroded ,mine was just a bolt into the engine block.

 

kenrahe,

I saw you posted the same question at the I-Boats forum and answered it there last week.

Bglad is on the right track. I would suggest that you clean all the electrical connections in the system, paying particular attention to both ends of the black ground wire at the pump.

Also make sure that the Trim Tab system is not taking the power from the ignition switch at the helm.

Let me know what you find and I will be delighted to help get the problem fixed.

Tom McGow
Bennett Marine