blower, bilge, nav light buttons dead

[lesaew]

Was out Fri evening in my '01 21V, had the nav lights on. By the time I raised the lift (engine was off) and reached to turn off the lights, all the lights on the dash had gone out. None of the buttons on that panel worked (bilge, blower, stereo, nav/anc). I pushed all the breaker reset buttons on the dash, checked all the fuses, checked battery terminal connections, checked connections on back on the dash, and found nothing.

Sat morning, I opened the engine hatch (bc the blower wouldn't work) a few minutes, and took some house guests out for a ride. We cruised for a while and tubed for a while. Went to take off and she sputtered and died. It wouldn't start (engine would crank but sounded like it wasn't getting fuel - tank at about 1/2). Reset the main breaker. Got towed in.

Tried to crank it after about an hour and noticed my nav lights came on when the key was in the ON position. Engine wouldn't crank.

I don't even know where to start with this one. Suggestions?

[noworries]

I'd start by cleaning the battery terminals and then work my way electrically forward. Could be another bad ground or loose connection. On second read, is your alternator working? What are your battery voltages?

[lesaew]

Don't remember specifically, but quick glance of the gauges, voltage looked normal.

Other than directly under the dash and at the battery, are there any places I should be looking for points of failure? Also, I noticed each one of the breakers on the dash (push buttons on the right) had 2 wires with the exception of the one labeled ACC. It had 2 leads but only one wire. I couldn't find any unconnected wires that would reach it. Is that normal?

[dogbert]

It's normal for the dash lights to go out when the key is off. Mercruisers are notorious for not starting if the voltage is low, so I'd check your battery to see if it's charged properly (take it to Autozone to get it tested). It may be that your alternator is not working properly and you ran down your battery. I had that happen to me last year.

Also, there are 2 inline fuses in your dash, one for the gauges and one other one that control something (maybe the buttons). You can find them by following the wires from your ignition switch. That may explain your Nav/Blower/Bilge not working.

If I had to guess, it's either a bad battery or bad alternator.

[lesaew]

right, there are actually 3 inline fuses behind the ignition switch, and all are good (used a tester, not just an eyeball).

Something I forgot to mention, sometimes I could hear a faint clicking sound (head under the dash) when I pushed the buttons, and sometimes not. Like 1 out of every 4 pushes would click.

[dogbert]

Hmm, maybe it's a short somewhere. I know some guys have had trouble with their TAPS button, where it would short out. Do you know if your TAPS is working?

[lesaew]

TAPS was working. And the engine would crank without hesitation. When I turned the key I could hear the fuel pump kick on, but it sounded like it wasn't getting fuel.

Duh, will check the fuel filter when I'm there next weekend.

[dogbert]

Also, check your distributor cap. The one on that engine doesn't last very long. It will cause your boat not to run.

[lesaew]

Update: I called my mechanic. Tracing down a bad ground is not my idea of fun. I will let you all know the results.

[lesaew]

Update: called my mechanic last Thursday, and he said he was banging his head on the boat all day. He found weak spark coming out of the distributor cap so he replaced the cap. It fired right up, he water tested it, put it back in the shop to install a battery disconnect switch, and then it wouldn't start. Again weak spark out of the distributor cap. Replaced the cap again, would not fire.

I'm afraid he's going to take it to the lake and sink it. Any suggestions?

[chpthril]

Update: called my mechanic last Thursday, and he said he was banging his head on the boat all day. He found weak spark coming out of the distributor cap so he replaced the cap. It fired right up, he water tested it, put it back in the shop to install a battery disconnect switch, and then it wouldn't start. Again weak spark out of the distributor cap. Replaced the cap again, would not fire.

I'm afraid he's going to take it to the lake and sink it. Any suggestions?

The strength of the spark will be produced by the coil, the cap, for the most part, distributes the spark to the proper cylinder. Weak spark is an ignition primary problem such as a bad coil or a coil with low voltage to it. Need to find a technician, someone with diagnostic skills.

[lee]

Try the sensor inside of the distributor cap. Merc had a bad batch in 2001.

[lesaew]

Just heard back from my mechanic. He replaced the distributor cap, plug wires, and coil. Spark was still intermittent. Turns out the tach is "going bad." With the tach disconnected the spark is consistently good.

As for the accessories, the connecting block under the dash is bad. Do I need to get that from Tige or is there an aftermarket recommendation? (I guess I need a set of guages too.)

[mneal]

Intermittent electrical issue are not easiest thing to diagnose and solve, without knowing the exact details of the transactions IMO not too fair to throw tech under the bus.

The strength of the spark will be produced by the coil, the cap, for the most part, distributes the spark to the proper cylinder. Weak spark is an ignition primary problem such as a bad coil or a coil with low voltage to it. Need to find a technician, someone with diagnostic skills.

[chpthril]

Update: called my mechanic last Thursday, and he said he was banging his head on the boat all day. He found weak spark coming out of the distributor cap so he replaced the cap. It fired right up, he water tested it, put it back in the shop to install a battery disconnect switch, and then it wouldn't start. Again weak spark out of the distributor cap. Replaced the cap again, would not fire.

I'm afraid he's going to take it to the lake and sink it. Any suggestions?

The OP is doubting the skills of the MECHANIC and ask for suggestions.

Just heard back from my mechanic. He replaced the distributor cap, plug wires, and coil. Spark was still intermittent. Turns out the tach is "going bad." With the tach disconnected the spark is consistently good.

As for the accessories, the connecting block under the dash is bad. Do I need to get that from Tige or is there an aftermarket recommendation? (I guess I need a set of guages too.)

Intermittent electrical issue are not easiest thing to diagnose and solve, without knowing the exact details of the transactions IMO not too fair to throw tech under the bus.

^^^^3 brand new distributor caps and and it's still not running When I made my recommendation, he was chasing a "weak" spark, not and intermittent spark.

Based on the info given, I stand behind my suggestion to find a skilled technician, with the proper tools, and the knowledge to use them. Sorry if this offends anyone, but I feel I am qualified to make this statement, I stayed at a Holiday Inn last night

Still not convinced it's a Tach "going bad", I dont think we have heard the last of this one.