Volt meter on dash all the way over to 18

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RobinsBill

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Heeerrre we goooo  :-\  Our brand new to us 1998 Beaver Patriot is running with the voltmeter pegged all the way over to 18.  Help? :-\
 
I would put a volt meter on the alternator output ASAP. It it is cranking out that many Amps, you don't want to fry your batteries and who know what with than kind of amperage.
 
The volt meter on the dash reads 18 volts. That has nothing to do with the amperage the alternator is putting out. Does your husband own a volt meter and does he know how to use it? If not you should hire a competent RV mechanic to fix it. I would look on Craigslist for a local mobile mechanic.
 
Could be the voltage regulator is not reducing the voltage output of the alternator. Agree with having good mechanic look at it before something blows up.
 
SargeW said:
I would put a volt meter on the alternator output ASAP. It it is cranking out that many Amps, you don't want to fry your batteries and who know what with than kind of amperage.

SeilerBird said:
The volt meter on the dash reads 18 volts. That has nothing to do with the amperage the alternator is putting out. Does your husband own a volt meter and does he know how to use it? If not you should hire a competent RV mechanic to fix it. I would look on Craigslist for a local mobile mechanic.

muskoka guy said:
Could be the voltage regulator is not reducing the voltage output of the alternator. Agree with having good mechanic look at it before something blows up.

Thanks Guys!  We will be getting a voltmeter and learning how to use it.  We won't be picking up "The Beav" for another week.  We are thinking we might just have the same mobile RV tech that not only did the "house" systems inspection for us, but he fixed a bunch of little this and that's.  AND he  showed us how to fix these things ourselves too.  He was also very reasonably priced.  And if it looks like the alternator, then there is an RV shop a little ways away.
 
Check the voltage in the dash cigarette lighter with any multi-meter set on the "20VDC" setting. It could as easily be the volt-meter malfunctioning. I wouldn't run the engine long with it showing 18V though. It may not only boil the batteries but it could fry sensitive engine based electronics..... even the radio may not like 18V for long. Could even burn out light bulbs.

Yes..... if the voltage regulator is malfunctioning and putting 18V to the batteries it is likely doing it at full amperage. The regulator should shut-off @ 14.8V. The amperage will boil the batteries in 30 minutes if that's the case..
 
If this is the dashboard voltmeter, we are talking about the engine alternator. You don't want an RV mechanic for that - it is a chassis issue. You may be able to get a mobile engine mechanic, but they usually don't do house calls for non-emergency problems. You can drive it to an engine &  chassis shop.

Check the voltage at the dashboard 12v outlet or other point on the dash to see if the system voltage is really that high. Could be a bad gauge or wire to the gauge.
 
RobinsBill said:
We will be getting a voltmeter and learning how to use it. 
Good idea. A voltmeter is almost essential equipment for an RV. You can get a nice digital voltmeter at any Walmart auto department for under $20, and you do want to get a digital and not an analog. Digitals are much easier to read. They are easy to use. You can Google instructions. It is a good idea to test the voltage of any shore power before you plug in. Make sure you are getting close to 120 volts. Too much or too little could cause problems with appliances.
 
Gary RV Roamer said:
If this is the dashboard voltmeter, we are talking about the engine alternator. You don't want an RV mechanic for that - it is a chassis issue. You may be able to get a mobile engine mechanic, but they usually don't do house calls for non-emergency problems. You can drive it to an engine &  chassis shop.

So, no RV repair shops...  Only chassis truck type places?  With the CAT, Freightliner, etc. logos?
Oh how much new stuff to learn!  :eek:
Here is the strange thing...  We took it to Peterson CAT for the mechanical inspection.  That is where the guy told us about that gauge being like that.  Of course the motor coach wasn't ours yet, but, they had a total lack of interest in having us back in for the maintenance or anything, should we purchase the coach.  In fact, when we asked them to work up a quote on the much needed maintenance, so we could present that to the owner of the coach, the guy flat out said "weee cccaaan... but you really don't want to bring it to us, we are expensive."
They run $98.00 an hr...
We asked him if it was charging at 18 volts, would it hurt anything?  He said, naw, just get it checked out when you get home.  We DID tell him that home was over the mountain and a couple of hours drive.
 
RobinsBill said:
So, no RV repair shops...  Only chassis truck type places?  With the CAT, Freightliner, etc. logos?
Oh how much new stuff to learn!  :eek:
Here is the strange thing...  We took it to Peterson CAT for the mechanical inspection.  That is where the guy told us about that gauge being like that.  Of course the motor coach wasn't ours yet, but, they had a total lack of interest in having us back in for the maintenance or anything, should we purchase the coach.  In fact, when we asked them to work up a quote on the much needed maintenance, so we could present that to the owner of the coach, the guy flat out said "weee cccaaan... but you really don't want to bring it to us, we are expensive."
They run $98.00 an hr...
We asked him if it was charging at 18 volts, would it hurt anything?  He said, naw, just get it checked out when you get home.  We DID tell him that home was over the mountain and a couple of hours drive.
If you drove it for a few hours like that, it's obvious that you engine based electronics are somewhat tolerant to 18v (if the gauge is actually accurate).

I would certainly check the water level on the batteries before starting the engine again. IF the batteries are low on water...... fill them to within about 1/2" of the top with "Distilled Water" only (available at most grocery stores). #1 killer of batteries is low water level. If the alternator has been putting out 18V, the water may have boiled out of the batteries.

This is all you need to check the voltage:
http://www.harborfreight.com/7-function-multimeter-98025.html

Turn the dial to the dial to the "DCV" range of settings and place the pointer on "20". Plug the red lead into the VWmA (Center) Jack. Plug the black lead into
the COM (Bottom) Jack. Turn the switch to "ON".....Carefully put the red probe in the center of the lighter socket and touch the black probe to the casing....... you should have the true voltage reading with the engine running (If the lighter works  ;)).
 
I see two possible issues..

One: Defective volt meter (hey it happens)

Two: Defective voltage regulator (This too happens from time to time)  HOWEVER, there are now two types of alternator systems.. On one kind the voltage regulator is a box, it may be metal, plastic, or epoxy... It is fairly low cost and easily replaced... That is if you can get at it (I mean they put stuff in RV's where a circus controtionist can't even get at it).

The other is built into the alternator.. and if that's where they put it OUCH$$$$$
 
For what it's worth, my experiance on old ford dump truck on farm.
It was randomly jumping back & forth from normal to 18 volts.
We pulled alternator & took to O'Reilly's to get it checked. They said it was OK. We asked how many volts it was putting out. They said we don't know, but it is charging.

We blew it out with an air hose & reinstalled, along with a couple new battery cables. Works great now. Do not know what the problem was.
 
Any auto mechanic can do that, 18 volts is way  too high.  Get it checked ASAP before you do some damage.
 
Thank you everyone!  We have not taken possession of the motorcoach yet...  It was only driven to Peterson CAT and back to the previous owner's home (not even a full hour).  However, let's add just a little more information and see if it makes any difference at all.
The first time we went to look at the coach, the owner had the chassis batteries hooked up to a charger.  It took quite a while to charge the chassis batteries enough to start the engine.  So, obviously discharged, and how many times over the years, we do not know, and those batteries are quite old anyway.  The woman's husband passed away in 2008.  She claims she starts the coach every month and runs it for half an hour, and her son takes it out for a few hundred miles a year for exercise.  The tags expired in 2011, so I'm thinking it hasn't been out for more than a year.
The "house" batteries were not working, old, and bulging. 
Before we arrived to fully inspect the coach, the mobile RV tech put in 4 new "house" batteries, and checked the distilled water in the chassis batteries.
After a day of inspecting all the "house" systems, we drove it the 15 to 20 minute drive to Peterson CAT, left it overnight for them to start their inspection in the morning.  Then drove it the same amount back to the owner's house.

We are not going to drive it home until this issue is resolved...
So, let us get this right...
1. Check the water in all batteries first.
2. Start the coach and check at the lighter with the multimeter to see if it really is at 18 volts.
3. If it is not charging at 18 and reads normal range, then it is probably the gauge?
4. If it is reading at 18 (or higher than it should be), take it in to a nearby shop that can test the alternator and or regulator?
 
RobinsBill said:
So, let us get this right...
1. Check the water in all batteries first.
2. Start the coach and check at the lighter with the multimeter to see if it really is at 18 volts.
3. If it is not charging at 18 and reads normal range, then it is probably the gauge?
4. If it is reading at 18 (or higher than it should be), take it in to a nearby shop that can test the alternator and or regulator?

Yes, and in that order.  If it's just the gauge, very easy repair.

And as stated above, some alternators have an internal regulator, and on some it's external.  Either way, not brain surgery to repair.  If it's internal, you can take the alternator to any Starter/Alternator shop and they can repair it without having to replace the whole thing....which is what I recommend.  They will use good quality parts....with a discount store rebuild, it may be offshore junk inside. 
 
May be a dumb question, but the OP is looking at a 1998 Beaver Patriot DP.  Just how difficult is it to access the alternator on one of those?
 
Molaker said:
May be a dumb question, but the OP is looking at a 1998 Beaver Patriot DP.  Just how difficult is it to access the alternator on one of those?

If it appears to be the alternator, we will not attempt to do this ourselves...  It goes to the mechanic  ;)
 
RobinsBill said:
If it appears to be the alternator, we will not attempt to do this ourselves...  It goes to the mechanic  ;)

If you have an alternator / starter rebuild shop near, call them....they may do the R&R work as well.
 
If it is already at a Cat garage, let them diagnose it.  Not rocket science - it's either the alternator or the gauge. And even if it is the alternator, it may be the voltage regulation circuit than the alternator itself.

Are you contemplating buying this "as is"? If not, advise the owner of the problem and stipulate it has to be repaired before you buy. Or negotiate a sales price that includes the necessary repair(s).
 
Gary RV Roamer said:
If it is already at a Cat garage, let them diagnose it.  Not rocket science - it's either the alternator or the gauge. And even if it is the alternator, it may be the voltage regulation circuit than the alternator itself.

Are you contemplating buying this "as is"? If not, advise the owner of the problem and stipulate it has to be repaired before you buy. Or negotiate a sales price that includes the necessary repair(s).

lol! It's not at the CAT garage...  The coach is at the previous owner's home in Klamath Falls, OR.  We are back at our home in Medford, OR.  The owner did come way down on the price due to a few maintenance and repair items.  We were staying at a hotel in Klamath Falls while the inspections and negotiations were going on.  Now we are home, setting up appointments etc. to get the coach brought up to date on everything.  Also waiting for the dynabeads that we ordered.  Gary, I'll send you a PM  :p
 

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