Sorting out electrical system issues on a new (to me) 2000 Catalina 36 MK II that I just took possession of. Looking for help with an alternator problem.
Before launch and initial test under power, I had yard replace charger with an inverter charger and also had some minor things addressed including tightening the alternator belt. Charger does seem to be charging both batteries.
On Sea Trial, we found that the tachometer wasn't working and the alternator did not seem to be charging the batteries. The alternator remained cool ever after engine was running a while.
The other thing we noticed is that the house electrical is only powered when the Battery Selector Switch is in the "2" position or the "All" position but is not powered when the switch is set to "1". That doesn't make sense to me if everything is connected properly based on the schematics I've seen.
There also seemed to be an MRBF block in the battery compartment that isn't connected. I assume it is there to deal with the "7 inch rule" for fused battery connections.
I want to start tracing wires to make sure things were wired properly with the spring launch and with the charger installation. I also will take the alternator for testing.
I wanted to see if anyone has thoughts or suggestions. In particular, where will I find the end of the alternator lead?
Thanks in advance.
Generally speaking I'd suggest a multimeter to check for voltage and continuity, a notebook and labelmaker to document what is there before and after changes are made. One change at a time, write it down in case you need to go backwards.
This seems different - if the boat yard replaced or repaired things all is supposed to work, or they are responsible until it does. If fuses in the battery compartment aren't connected whoever did the work ought to be fired.
Find an experienced ABYC certified marine electrician to set things right. It may set you back a few weeks and some dollars but it is an investment in peace of mind on your boat.
Denis
Brazen Article #1925
2001 Catalina 36 MKII
While you are tracing wires, I highly recommend installing a #8 ground wire black insulation from ground lug of the alternator to the non-battery side of the shunt.
Your alternator may have become damaged if it momentarily lost its ground connection which is commonly provided through its hinge bolts.
If you have a dedicated starter battery, the alternator output should be connected to this battery with no switch to disconnect it. Then a large cable should be connected to the positive lug and through a switch connected to the common lug of the house battery switch. The alternator will charge any house battery that the switch is connected to.
Sail La Vie 1999 Catalina 36 MKII, M35B-17031, Coyote Point, San Mateo, CA
About Sail La Vie
On my 2001 next to the battery 1/2/both switch, there is also an engine DC power switch. If its off the alternator gets no power. Also, the engine starter won't turn.
Test the battery terminal at the alternator. If there is no power there, then the alternator isn't connected to the batteries, so it wouldn't be able to charge. You can also test it carefully while the engine is idling. If the voltage doesn't jump to 14 volts or so, the regulator isn't exciting the circuit, so it might be a regulator issue, or the alternator is bad.
Update:
Thank you for the advice.
Was able to use multimeter to trace things out. Alternator is connected to the battery switch common post through the rotary engine switch that is on the same panel (under the lunch table). I also find I get battery voltage back to the connector on the alternator so all the wiring seems intact (and now sorted out). Alternator is likely bad and I've already removed it to test/replace.
In terms of the problem not being able to power the house of battery 1 - seemed to be related to a dirty 1/2 switch. Using a ohmmeter, post 1 wasn't connecting properly to the common post when switch was set to "1" but was connecting when set to "Both". I dissembled everything and worked the switch a bit to clean contacts. Recheck showed it was working properly - reinstalled and all is good there.
The MRBF block was to fuse the line from the charger/inverter to the battery - now installed properly.
Hopefully once the alternator is replaced, I'll have a properly working DC system.