Alternator/Voltage gauge problem, 5411 diesel

[MarkSF]

Originally Posted by Marcobowow

MarkSF,

Thanks for that. You've been very helpful to me. I'll go to the boat, which I've owned since July of this year, and either get the new gauge, or hook up the old one and see if my alternator voltage improves.

I bought this boat in July of this year. I've never owned a large sailboat, just lasers and hobie cats, so this has been quite an education, and expense. Actually, it's been fun, especially learning about a diesel engine.

Marine Sail I haven't read that article, but I will, thank you too.

I'll get the proper gauge back in the boat, which could take a couple of weeks due to Christmas, and I'll post how it went.

Thanks,
Mark

I've been in the same boat (ouch) since getting mine in April. I recommend Don Casey's book "Complete Sailboat Maintenance Manual"

[WanderingStar]

Don't replace your alternator without having it tested, I think a good auto shop should be able to do it. In my experience charging problems are often from voltage regulators, or wiring trouble.

[Maine Sail]

Originally Posted by WanderingStar

Don't replace your alternator without having it tested, I think a good auto shop should be able to do it. In my experience charging problems are often from voltage regulators, or wiring trouble.

There are SOOOOO many problems with these early Universal alt, wiring harness, ammeter & glow circuits that it is often best just to re-wire everything while you're in there. Some of these have started fires. Doing the wiring harness upgrade is a VERY wise choice.

I'd start with addressing the wiring then if the alt does not put out have it tested & fixed. Could be blown diodes, bad connections in the original factory wiring or a bad VR...

[Marcobowow]

Marine Sail,

Do you think there might be any situations where you didn't have to replace all the wiring and parts?

I don't use that much DC power.

I have a 1982 C27 and I use the blower, of course the glow plugs, and the lights, and I use these for only short periods and infrequently. When we stay on the boat, we use shore power and I just installed the Smart Plug system.

My trailer plug connectors looks fine, for a 29 year old boat. I see no signs of wear or melting wires. The old amp meter in the panel didn't work, but didn't seem to affect the charging of the batteries. The PO said he had to change batteries every three to four years.

Mark

[Maine Sail]

Originally Posted by Marcobowow

Marine Sail,

Do you think there might be any situations where you didn't have to replace all the wiring and parts?

I don't use that much DC power.

I have a 1982 C27 and I use the blower, of course the glow plugs, and the lights, and I use these for only short periods and infrequently. When we stay on the boat, we use shore power and I just installed the Smart Plug system.

My trailer plug connectors looks fine, for a 29 year old boat. I see no signs of wear or melting wires. The old amp meter in the panel didn't work, but didn't seem to affect the charging of the batteries. The PO said he had to change batteries every three to four years.

Mark

It really does not matter "how much DC" you use. The trailer connectors are dangerous if you want to continue to push large amounts of DC current through them. This means glow, and alt circuits.

At the very least the alt should be direct wired to the house bank or jumped direct to the starter post thus bypassing 20 feet +/- of small gauge wire and one or two trailer type connectors that are very, very, very well known for high resistance leading to fires or at the least melting of the wires..

You don't need to replace all the wire, unless it is melted, but you WILL need to clean the wire before re-terminating if it is oxidized. Some ring terminals and a terminal strip will cost you about $20.00. A short piece of 6GA - 10GA wire to jump the alt to the starter post will cost about $4.00 at the most...

This is a serious electrical blunder that has caused many fires. It constantly amazes me that there are still boats around that have not fixed this.

In fact you've reminded me that I should post that article here too..