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Alternator output

Yahoo Message Number: 64968
On a couple of recent, short trips I noticed that my Silverleaf PC is reporting battery voltage of around 12.5. Sometimes down to 12.3 and sometimes up to 12.8. I was surprised to check an old log file from a trip back in Feb. and see that the same thing was going on. I'm used to seeing mid 13's but, my echo charger didn't work for a long time so the chassis battery was always pretty depleted when I started out. What voltages are you used to seeing? Assuming somethings wrong, any thoughts or experiences that would shed light on where to start? My first guess would be the input side of the alternator - anyone know if it's fused or what the routing is?

Thanks,

Greg Jones

'03 Intrigue 11571

Re: Alternator output

Reply #1 –
Yahoo Message Number: 64971
Greg,

The echo charger only comes into play when your not running and on shore power or generator and keeps the chassis batteries topped off.
While running the alternator should be showing around 13.7 on your Silverleaf. If your in the twelves, I would suspect the regulator or alternator. Mine has am adjustment switch on the alternator to change the charging voltage. Put a meter on the chassis batteries with the engine running and if your not in the high 13's at least you know where to start.

Tom

01 Magna 5999

Re: Alternator output

Reply #2 –
Yahoo Message Number: 64972
Trust me, your alternator is bad or going bad. I'm on my third alternator and both of the first two exhibited these exact symptoms down to the tenth of a volt when they went bad. You can limp along for a while (maybe a year in my case) doing things like running the generator while underway to keep the batteries charged up, but eventually you'll have to bite the bullet and replace the alternator.

Brian Davis

'05 Intrigue OVTS
Coach #11901

Re: Alternator output

Reply #3 –
Yahoo Message Number: 64974

Greg:

Mid to high 13's. Any decent shop should be able to test the alternator quickly at minimum expense. Replacing/rebuilding an alternator isn't cheap; not sure if the regulator is internal or external, most seem to be internal.

Bob (rthandren@...)
'05 Inspire 51178

Re: Alternator output

Reply #4 –
Yahoo Message Number: 64976
Quote
Quote from: Greg"
Greg,

I'm on my third alternator. Someone is producing junk! On the Silverleaf I read 13.8 pretty consistently. Lower in the AM just after starting the engine and bringing in the slides but it recovers pretty quickly to about 13.4 and shortly after to 13.8 Lyle Wetherholt
04 Intrigue 11740
> On a couple of recent, short trips I noticed that my Silverleaf PC is reporting battery voltage of around 12.5. Sometimes down to 12.3 and sometimes up to 12.8. I was surprised to check an old log file from a trip back in Feb. and see that the same thing was going on. I'm used to seeing mid 13's but, my echo charger didn't work for a long time so the chassis battery was always pretty depleted when I started out. What voltages are you used to seeing? Assuming somethings wrong, any thoughts or experiences that would shed light on where to start? My first guess would be the input side of the alternator - anyone know if it's fused or what the routing is? >

Thanks,

Greg Jones

'03 Intrigue 11571

Re: Alternator output

Reply #5 –
Yahoo Message Number: 64979
The voltage regulator seems to be made in China and are not very good. They produced a bunch of weak units. Later units are suppose to be better. They are easy to replace but requires taking the alt. off. A good rebuild shop will check and replace bearings as needed as well as regulator, cheaper then a new unit. Will last as well as a new one. Our alternators are very high output and run the high output for a long time. Takes a long time to bring up all the batteries, coach and chassis. High output means lots of heat. Alternator issues are a way of life on fleets. Always surprised at the number of alternator failures on our school bus fleet. A bus would be shut off and then not start from a alternator failure. Seemed to happen very quick. Busses have a high current use. One way to take the load off the alternator is to have the in house charger charge the batteries as much as possible. Otherwise this is normal business with a diesel charge system.

By the way, full charge will go up to 14.2 to 14.8 then drop back to 13.2. Depends on meter system, one may not see the 14.2 until the batters are brought up. Anything under 13.2 after some run time says something is not right. Takes high idle for the alt. to produce, idle does not do it.

Leonard Kerns
97' Magna 5418

Re: Alternator output

Reply #6 –
Yahoo Message Number: 64980
Greg,

Your alternator is going kaput. 12.3 isn't enough to keep things going so I would have it looked at pretty quick. If you find yourself out and the output is low, you can start the generator and bring the voltage back up into the 13.8 range, this being done by the inverter/charger. I had to do this for a couple of thousand miles and it works fine. If you buy new, get ready for a $700+ bill.

Don

'02 Intrigue #11427
'02 Intrigue #11427

Re: Alternator output

Reply #7 –
Yahoo Message Number: 64981
Mine went out last year and I took it off and took it to a alternator repair shop. The rotor / stator/ regulator were all fried. Cost $86.00 with tax.
Kevin Burns
00 Affinity

Re: Alternator output

Reply #8 –
Yahoo Message Number: 64984
Greg... I don't use the silverleaf, so have no idea of how accurately it reads the battery voltage...
Suggest you invest in a good quality Volt/Ohm/Milliameter (VOM) (Fluke makes a good one)
With the engine running, measure the voltage at the chassis battery terminals with the VOM... If your alternator is OK, the voltage will be 13.8+...
Re: the battery itself... turn off the engine and the Echo charger... Connect the leads from the VOM to the chassis battery terminals and monitor the voltage... It should measure 13.8+ volts but will rapidly (within a couple of hours)drop to 12.66V, which is the real, useable voltage of the battery when fully charged... The battery voltage should stabilize at 12.66V if the battery is in good shape...

buck

k7wn, '99magna5653, C10, 4060HD

==============================================

Re: Alternator output

Reply #9 –
Yahoo Message Number: 64990
Greg, my Silverleaf reports 13.8 to 14.1 volts. I have verified that reading with my multimeter.

George in Birmingham
'04 Allure 31038
George in Birmingham
2003 Magna 6298

Re: Alternator output

Reply #10 –
Yahoo Message Number: 65033
Ken here Retired Cat Tech. Today you can just bring your rig to a good Starter Alternator shop. Working on engines all my life our fleet trucks were taken to the Alt/Starter shop and they put on a computer and also load tested the Alternator. A failing bearing noisy etc. we had it rebuilt. In most cases the rebuild shop uses better components then the factory. The load test checks out the entire charge loop, Breakers, Fuses etc. I use to rebuild them years ago but today its cheaper to get the shop to do it, Also starters can be checked. Ken 99 Allure

Re: Alternator output

Reply #11 –
Yahoo Message Number: 65052
Thanks to everyone who responded. As usual, a wealth of information in this group.
I have checked that voltage at the chassis battery with the engine running and it is within a tenth of the Silverleaf reading. Even though I'm 3,000 miles from home I think I'll limp it back. My favorite guitar pick is a great wedge for the boost switch so, between a full chassis battery charge and 2 full Lifelines, I think it will probably make the 4 or 500 mile days I usually travel and then, the generator can help if needed.
Thanks again but, next time please make the solution easier and cheaper!

Greg Jones

'03 Intrigue 11571

Re: Alternator output

Reply #12 –
Yahoo Message Number: 65054
Ugh! I'd be careful on the wedge on the switch without knowing if the solenoid is rated for continues duty or intermitting. Could overheat the solenoid and burn it out. Think a better work around is to run the generator and let it charge things up. A diesel does not take much going down the road. Burn out the solenoid and may have other issues.

Leonard Kerns
97' Magna 5418

Re: Alternator output

Reply #13 –
Yahoo Message Number: 65112
On our '05 Intrigue that solenoid is always on when the engine is running so the alternator can charge the house batteries. The solenoid is triggered by an oil pressure switch. When our alternator went out, we ran the generator while driving and that charged the house and chassis batteries at the same time. Our alternator was smoking and had failed completely. This is when we found out from CAT that the C13 only runs the AC compressor and alternator from the belt and everything else is gear driven off the engine. We drove the coach from and to the CAT service yard with the belt off and the generator running and it kept the chassis battery fully charged.

Bob

2005 Intrigue 11872

Re: Alternator output

Reply #14 –
Yahoo Message Number: 66206
Thanks for all the input. I easily limped it home, all 3,000 miles, by running the generator and running off of the chassis and house batteries until they got low. I discovered that, like Bob's, my Intrigue does make the boost solenoid when the oil pressure comes up. A local auto electric shop had a new replacement for $280, not branded Leese Neville but, from the same manufacturer. Not the easiest replacement but, doable and done and all works well now.

Greg Jones

'03 Intrigue 11571