[Wong]

Shabah 182 won't start. No electrical power. Except power trim works. Therefor not battery issue.
No power to gages or radio.

Replaced ignition switch but that didn't fix the problem.

[mikeyt]

I'm assuming you are asking for help here..... First thing to check is your ground. Follow the groundwire from the battery, take the connections apart, clean and reconnect. There should also be a ground block on the transom near the battery that can be cleaned. Bad grounds / poor connections are the usual cause of these problems. You can also check the fuse block up underneath the console.

[Wong]

Did this. Still wont start

[ColoradoDiablo]

As mikey said..................connection issue.
Take apart the main wiring harness plug that runs to the front of the boat and clean the connections , use dielectric grease , plug back together.
Kinda hard to help when your responses are short with no real info as to the symptoms of the problem.

[allz28]

Try bypassing the push button circuit breaker. On my 5.7l it's right on top of the engine. When mine went bad, I had the exact same symptoms: no power to starter, but I could raise and lower my lower unit.

[mikeyt]

That's a possibility too. This from the Mercruiser manual:

1 A circuit breaker provides protection for engine wiring harness
and instrumentation power lead. Reset by pushing RESET button.
In an emergency, when engine must be operated and cause for high
current draw cannot be located and corrected, turn OFF or
disconnect all accessories connected to engine and instrumentation
wiring.
Reset circuit breaker. If breaker will not reset, electrical overload has
not been eliminated. Further checks must be made on electrical
system.
2 A 20 amp fuse may be located in ignition switch “I” terminal lead
to protect electrical system. Check for blown fuse if key is turned to
START and nothing happens (and circuit breaker is not tripped).

[Wong]

This weekend , after trying everything I could think of, I got a mechanic to look at it. He figured out that it was the 90 amp Mallory starter fuse. Going to replace this next weekend. Looks like I have the answer.