1976 Mariner 2876 trim tabs

[Ctmangrum]

So I didn't find anything in the original manual about trim tabs. Im troubleshooting to see if there is an actual issue or im just not doong something right. What has to be on in order to operate the tabs? Engine running? Engine just turn to ACC? Just battery switch on the cranking battery? Should there be a long delay before they move? Fuse is fine. Thanks.

[Viper]

Typically they're on their own circuit independent of the engine and other systems, so nothing else has to be turned on for them to operate. I assume they're hydraulic, when you operate the control, can you hear the pump running? Have you checked the fluid level? What brand is it? Bennett, Instatrim Boat Leveler, Teleflex?

[Cooler]

This may not be accurate for 77, but Carver was pretty standard about these techniques. Your DC main switch would need to be on, and battery selection switch not in off position. If there is a connection through an ignition switch, ( doubtful ), it would be to the port side ignition switch. Like Viper said above, they are normally direct, independent circuit. They are pretty quiet, until they hit max setting. Maybe that is why you think there is a delay, there should be no "delay". If you can reach the actual tab, then grab one and feel the up/down motion. Remember also that the button on your tab raise/lower is opposite of which tab you are adjusting. Button on the right side of the switch is actually operating the port side tab. er

[Ctmangrum]

Source of the post Typically they're on their own circuit independent of the engine and other systems, so nothing else has to be turned on for them to operate. I assume they're hydraulic, when you operate the control, can you hear the pump running? Have you checked the fluid level? What brand is it? Bennett, Instatrim Boat Leveler, Teleflex?

Bennet hydraulic an I didn't hear the pump but, i was also by myself in a working boat yard so it would be hard for me to hear from the flybridge. Ill get someone to stand by the bilge and listen. If there's no pump sound, what are you thinking? Ive done no troubleshooting yet.

[km1125]

There are a couple solenoid-type valves and the hydraulic pump. If you're not hearing the pump, then I'd first check breakers and fuses to see if you're getting any power down there. If the pump runs but there's no up/down motion, then it's either the connections to the solenoid valves or the valves themselves. Bennett has a lot of troubleshooting info on their site too, with wiring diagrams. Check the fluid level in the reservoir too. Leaky seals on the tab units will cause a loss of fluid. There's only a couple O-RIngs in those and they're easy to replace.

[Cooler]

If you are in a boat yard, I assume you mean the boat is on blocks, on the hard. Check to see if the batteries are disconnected. Lot of yards require you to disconnect the batteries while the vessel is in storage status. Are the blowers working? er

[Viper]

As km said, there's a few things you can check at the pump itself. If she's been in a salt water environment, you'll want to check the control switches as well, salt air and spray will corrode them. Also check the harness plug and ensure the contacts are clean and free of corrosion. First get someone to operate the switches while you're down below listening to the pump. If the pump doesn't work, you'll need to determine whether it's getting power or not when the switches are activated.

[Ctmangrum]

Source of the post If you are in a boat yard, I assume you mean the boat is on blocks, on the hard. Check to see if the batteries are disconnected. Lot of yards require you to disconnect the batteries while the vessel is in storage status. Are the blowers working? er

Its on the hard and i have power. Im currently "sprucing up" the boat.

[Ctmangrum]

Source of the post

Source of the post
Typically they're on their own circuit independent of the engine and other systems, so nothing else has to be turned on for them to operate. I assume they're hydraulic, when you operate the control, can you hear the pump running? Have you checked the fluid level? What brand is it? Bennett, Instatrim Boat Leveler, Teleflex?

Bennet hydraulic an I didn't hear the pump but, i was also by myself in a working boat yard so it would be hard for me to hear from the flybridge. Ill get someone to stand by the bilge and listen. If there's no pump sound, what are you thinking? Ive done no troubleshooting yet.

They worked with just the battery switch on. I was just testing with the wrong circuit tester and was not showing any power. (110v instead of 12v). Rookie mistake.