Volt gauge does not match battery

the read out on the volts gaug

the read out on the volts gauge shows up to 1.5 v's less than what a voltmeter shows on the battery terminals. Any thoughts on why they dont match or is the gauge simply stuffed? (I have cleand the conections on the back of the gauge.

"Put your multimeter across th

"Put your multimeter across the terminals on the back of the gauge. If it reads the same as across the battery your gauge is incorrect. Replace it if you want.

If the multimeter reads the same as your gauge you have a voltage drop along the loom somewhere, maybe in the main connector or the earth return."

"Ayuh,...... That makes Perfec

"Ayuh,...... That makes Perfect sense...."

"I don't think most marine

"I don't think most marine (or auto) voltmeters are more accurate than that anyway. All you really want to know is relative voltage. If it's high whilst underway, you are charging OK, if not, then you have a looming problem and best be heading for the marina. At least that's all I expect mine to tell me.
Rod"

"Andrew:

What is the volt

"Andrew:

What is the voltage at the starter? If it is not the same as the battery posts, either the connectors are corroded or the wire is corroded internally. A set of new battery cables can solve alot of electrical gremlin problems.

Old boats like my 87 Baretta end up with a number of internally corroded wires. I just finished a complete re-wire which included new gauges, switches and sending units on my 4.3L from the dash to and including the engine.

Whenever I found a corroded connection, I tried to strip the wires back to clean copper but it just went on and on and on. A few times I was lucky and found clean copper and soldered a jumper in place. I finally got tired of constantly working on corroded wires and connectors and replaced the entire wire system.

What I found with the old harness were a number of the wires on the engine; the starter, alternator and the fuel tank and trim motor relays, etc. were corroded. Apparently the copper wire corrosion slowly worked its way inside the insulation jacket and turned the shiny copper strands of the wire to dull and dark colors.

Since last year I refurbished the entire transom, stringers and flooring, I decided from an ELECTRICAL FIRE hazard point to replace all the wires. Corroded wires have been responsible for countless fires in boats, cars and home appliances.

During the process I tinned the copper ends of the wires and soldered them to the connectors and then shrink wrapped each connector. Any connectors exposed to the elements (coil, relays, sending units, starter and alternator were installed and then given a shot of clear battery protector spray to seal them from the elements. Lots of time went into the re-wire project, but it was worth it to me.

Incidentally, I purchased all new gauges, switches and harnesses on eBay from reputable suppliers at a great cost savings. My parts cost was less than $275 excluding a new alternator and reman. starter which cost me $260. For example, the set of 7 new Faria gauges cost me $100.

Good luck, Guy"

Thankyou for your thoughts the

Thankyou for your thoughts they were very help full. I think that there was a connection problem on the earth. But I will continue the checking. Cheers