Not Seeing a Charge

[starfish]

Need help!

I have a 2005, 350 Hull #333
I am not seeing volts while the engine is running (at 1500-2000 rpm) at the helm. I am showing batteries (new in 2022) fully charged but when the engine is running I am showing a negative on my battery terminals. Just had the alternator tested and it is showing "good". Where do I start trouble shooting?

Thanks
Ed

[wolfe10]

Need help!

I have a 2005, 350 Hull #333
I am not seeing volts while the engine is running (at 1500-2000 rpm) at the helm. I am showing batteries (new in 2022) fully charged but when the engine is running I am showing a negative on my battery terminals. Just had the alternator tested and it is showing "good". Where do I start trouble shooting?

Thanks
Ed

Ed,
We need some clarification on this:

When you say you are "not seeing volts while the engine is running" are you referring only to the gauge at the helm or as asked below have you measured voltage at the batteries (i.e. is this just a gauge or wiring to gauge issue or is the alternator actually not charging)?

And, when you say "when the engine is running I am showing a negative on my battery terminals" what do you mean-- discharge (more amps discharged than charging), other??

With your digital voltmeter, check battery voltage with the engine OFF and then with it running at 1500-2000 RPM. Let us know what you find.

[starfish]

Good morning, Ken and all else,

In response to your message and anyone else:

My volt meter at the helm is showing 11 volts with engine running. My batteries are showing 12.2v (at both batteries when engine is running. When the engine is NOT running I am showing 13.27 at each battery.

I am only guessing the RPM as my tach is not working at the moment either.

I have not yet opened the "dash" to check all the connections for corrosion or lose connections, that is my next task. Please let me know what the next steps should be.

Thanks to all,

Ed


Ed,
We need some clarification on this:

When you say you are "not seeing volts while the engine is running" are you referring only to the gauge at the helm or as asked below have you measured voltage at the batteries (i.e. is this just a gauge or wiring to gauge issue or is the alternator actually not charging)?

And, when you say "when the engine is running I am showing a negative on my battery terminals" what do you mean-- discharge (more amps discharged than charging), other??

With your digital voltmeter, check battery voltage with the engine OFF and then with it running at 1500-2000 RP

[wolfe10]

Ed, that is a real puzzler.

Please verify that you are not on shore power or have a generator running (i.e. the converter or inverter/charger as a second source of charging). Two simultaneous charging sources can give very confusing results.

If the battery bank is in good condition, at rest (no charging and no discharge) voltage will be about 12.7 VDC. Anything above that is just surface charge and will dissipate quite quickly.

But, even dropping from 12.7 to 12.2 VDC rapidly when the engine starts is a HUGE drop= huge discharge.

A non-working alternator (producing zero amps) would not do this-- you would have a small drop caused by the draw of the starter, then have voltage remain fairly steady-- so maybe 12.5 VDC.

Have not noodled through what would happen if positive/negative were reversed-- maybe an electrical engineer can more reasonably address if that could be possible and what the ramifications would be.

[starfish]

Hi Brett,

I am connected to shore power, however, I have my switch turned off to the shore power during this troubleshooting exercise.

As an fyi, everything was perfectly fine, tach was working, alt was charging perfectly. Then mysteriously I noticed my "reverse polarity" light on my panel was illuminated. I immediately unplugged my shore power line and turned everything off. A few days later is when I notice all the current issues with my Tach and the volt gauge at the helm showing only 11. And here we are. I don't know if it is all related but it certainly muddies the water.

Does this change any of your thoughts?

Thanks
Ed

[wolfe10]

Ed,

Sorry, but what damage reverse polarity could have done is "past my pay grade".

Probably need a complete inspection of both 120 VAC and 12 VDC given both have recent/current issues.

I would say the same if the boat had experienced an electrical lightening strike.

[ElizabethG]

Hi Ed,

Let's take a few steps back...

You stated...

"As an fyi, everything was perfectly fine, tach was working, alt was charging perfectly. Then mysteriously I noticed my "reverse polarity" light on my panel was illuminated. I immediately unplugged my shore power line and turned everything off. A few days later is when I notice all the current issues with my Tach and the volt gauge at the helm showing only 11. And here we are. I don't know if it is all related but it certainly muddies the water."

With shore power connected, are you still getting the reverse polarity light coming on? If so, let's get that squared away first.

Bill
2004 C350, #193
Atlanta (Home) / Charleston, SC (Boat)

[TEM58]

Ed,
There does seem to be a lot going on that may or may not be related. As far as the DC charging from the alternator perhaps try the low hanging fruit first. If you haven’t already done it, I recommend cleaning the connections from the alternator back to the batteries— especially connection at the starter. When you have the pedestal open you can also exercise the rotary switch on the back of the tach. It’s notorious for causing tach issues. There’s an explanation on the electrical forum but it’s very simple to do. Hope you find the issue soon, but please let us know how it’s going.

Tim

[starfish]

All, firstly when I unplugged from my shore power supply and simply reconnected in a different outlet the reverse polarity light is now gone. Secondly, I purchased a new alternator that did NOT have a blue wire coming from the alternator with a bullet connector which I am assuming is the "excite" lead for the internal regulator. Still not seeing a charge. I have contacted the company I purchased the alternator from to see what their response is for the lack of that wire. Hopefully I will hear from them today.

My next question is this; does the volt reading from the Alternator go through the Tach and then to the volt meter at the helm? Or does it go directly to the volt meter at the helm and then to the Tach. As an FYI, my Tach is still NOT responding. I am left scratching my head and just cannot figure out what I am missing.

Thanks for all the advice.

Ed

[ElizabethG]

Ed,

Here is the service manual for the M35B which includes testing your alternator; https://www.westerbeke.com/technical%20 ... al_man.pdf

There were two types used by Catalina; Mando on page 72 and Prestolite on page 82.

Before I upgraded to a larger alternator, I had the 50 amp Mando. I'm guessing you have the Mando as well.

Starting on page 94, you will find the wiring schematics. There are also two different helm panels listed in the schematics; Captain and Admiral.

So, depending on which alternator and panel you have, you should be able to determine what the wiring is between your alternator, batteries and helm instruments.

Bill
2004 C350, #193
Atlanta (Home) / Charleston, SC (Boat)

[starfish]

Good morning, Bill,

As I am the 2nd owner of my boat I can only assume that the original owner, Bill Templeton, changed the alternator to a Delco Remy 7294103 which has spade connected to the #2 terminal on the back, a positive terminal and also and EXCITE wire that I assume controls the internal regulator. The alt tested positive at a local Auto Zone, I purchased one anyway but it did not come with an EXCITE wire so my assumption is that it will not work and it did not correct the issue of no positive charge on my helm volt gauge and still nothing on my tachometer. So I am still not sure if the tach issue is related to the "no charge" issue. Have been hoping someone might be able to explain that to me.

Thanks for your response, Bill, it is appreciated.

ED

[ElizabethG]

Hi Ed,

Yes, you will need the exciter wire/terminal.

I may be wrong, but that is what "turns on" the alternator when spinning.

Without it, the alternator will not charge your system and your tach will not work.

Bill
2004 C350, #193
Atlanta (Home) / Charleston, SC (Boat)

[starfish]

So, would I be correct in "assuming" the Tach controls the charge? Meaning, if the tach is not moving the volt meter at the helm will NOT be showing a charge? Should I be looking into replacing my tach if the alt is working properly but not charging? A conundrum for sure.

Ed

[ElizabethG]

Hi Ed,

I'm not sure I understand your question...

The tack receives its power from a red wire (positive) and a black wire (negative) found within the instrument pedestal.

The alternator provides a signal to the tach. Your tach should have a direct connection to your alternator. Double check, but I think it's a brown wire.

In order for the tach to work, it must have the 12 volts noted above AND the signal from the alternator also noted above.

The volt meter at the helm also receives it power from the same red and black wire noted above. When you turn the key on, the volt meter should register the voltage even if the engine is not on.

Bill

[starfish]

An update for all you wonderful 350 owners: Yesterday I replaced the Alternator and still no charge. I put the altimeter on my Tach leads and it appears no sign of "excite" there still. My batteries and my volt meter at the helm are all showing no sign of being charged either.

The wonderful previous owner has signed on to the issue and I feel relieved that help is on the way. If you all don't know Bill Templeton (see Mainsheet magazine) he is the 350 Guru and unlike most previous owners he actually left me the boat in better condition than when it was new. Will certainly keep the forum up to speed as I move forward. Please continue to offer suggestions!

Thanks to all
Ed

[starfish]

Some have asked "what alternator are you using"?

Attached is the Delco-Remy 7294103 which is a direct replacement to the alternator that was with my boat.

The BLUE wire coming out of the back of the alternator is what I believe to be the "excite" wire. It was attached to the wire that I believe goes to the helm; this wire IS NOT on my replacement alternator.

There is a jumper on the new alternator which goes from the #2 spade to the "Bat" (red) post. A white wire is now going from the #1 spade to the "excite" wire to the helm. I have since removed that wire as there was no change to the no charge issue that led to this posting. Still no charge and no Tach.

Hopefully there is a more knowledgeable sailor reading this and can help.

Thanks
Ed