Alternator output voltage

[Kevin Schitoskey]

I noticed the voltage gauge on my dash was showing 16V (!}, so I pulled out my trusty volt meter and checked the voltage on the right side 12 volt box.  The voltage right out of the alternator (going to the battery isolator) to be 14.9V.  Is this still excessive?

I've read the stock gauges are notoriously unreliable.

Thank you,

Kevin

[Benjamin]

I don't know what system you have on that Dynasty as far as a diode based isolator, vs a relay like a BIRD.  14.9 might be normal for a diode isolator.  Check the battery voltage on both banks. Should be right around 14V running.  Might change a little depending on temperature, how full the batteries are, and how long the engine has been running. 

[TomV48]

1 hour ago, Benjamin said:

I don't know what system you have on that Dynasty as far as a diode based isolator, vs a relay like a BIRD.  14.9 might be normal for a diode isolator.  Check the battery voltage on both banks. Should be right around 14V running.  Might change a little depending on temperature, how full the batteries are, and how long the engine has been running. 

I concur.   With ours I run a 40 amp DC to DC that puts about 50 amp load on the alternator to charge 40.   With that I see 13 -14 volts running voltage but do see about a volt or so drop if I put the headlights on 

[Tom Cherry]

OK....My comment...without looking or having your prints, the TRUE voltage that you should be, or that I would be measuring is the charging voltage to the batteries.  I would, with the engine running, measure the voltage on the Chassis Battery.  14.9 is typically a bit excessive.  Ordinarily, it will be in the 13.9/14.1 range....and that is a relative number watching my digital gage up front...which might me a bit off.

BUT, the VOM reading on the battery while the engine is running would be by test....as that is coming directly from the Alternator.

OK...a little more research...  CURIOSITY...I suspect that you have prints....  I pulled the 1999 Executive and we have them...but, they were scanned and hard to read unless you piece them together.  I DID look at the 2001....as well as the 1999.

Your measurement point, the ALT terminal on the isolator should be, as you stated, directly from the Alternator.  Maybe a tad lower...but CLOSE...

My THOUGHTS...  Your regulator is a bit funky. 14.9 is a bit high....should be a full volt lower.  The RULE of thumb here is to Rebuild, with OEM Leece Neville Parts....ordered directly from a LN Distributor.  Also put in NEW DIODES....regardless if the shop says..."Tests OK".

NOW, there have been some successful conversions to other brands. @vanwill52 has posted a lot on the DUVAC conversion.  You can search.  USE duvac in the search box.  Then click on EVERYWHERE.  Choose Topics...  MANY different topics and scads of post our there.

That's my take....  Find a good shop or DIY, but understand the circuitry and what you have to do make it work properly...

[Kevin Schitoskey]

I really appreciate everyone's input.  Very thorough and insightful.  I do have the electrical schematics and I'll take your advice and have the alternator looked at.  It is easy to access and we have a good shop in the area.

Again, thank you all - this site is an incredible resource.

Kevin

[Benjamin]

The alternator voltage is not the voltage to worry about.  The voltage at the batteries is the correct voltage to check, as the alternator is usually wired to supply correct voltage at the battery, and may need that extra volt to account for the voltage loss through the isolator and wiring.