phorner
11-25-2008, 04:50 PM
This past summer, we travelled just under 7,000 miles and every once in a while, the dash warning light would come on indicating that the chassis batteries weren't being charged. This would usually occur during the first 20 - 30 minutes of driving, then everything would be OK. Sometimes, it would not come on at all for days. I discussed this with Jon and I agreed to simply "keep an eye on it." No problems on our way to Mobile and back.
A couple of days ago, I started up the coach and sure enough, the dash warning light came on again...... and stayed on. Checking the voltage meter, it was clear that the alternator wasn't charging the chassis batteries. A quick PM once again to Jon and he gave me the good and bad news.... it was either the alternator or the voltage regulator. I was sure that a new alternator was in my future, since I had already replaced the 12 volt house battery alternator last year.
Jon gave me clear instructions as to how to diagnose the problem. Check the battery voltage with the engine running. Now, jumper between the "field" terminal and the "positive" terminal on the voltage regulator. If the voltage stays the same, a bad alternator is indicated. However, if the voltage rises, a bad voltage regulator is the culprit.
I hooked up the multi-meter and convinced Janice that she should be the one to hold the jumper wire between the two terminals on the regulator, as only a trained professional could interpret the meter readings and besides, she has curly hair already :eek:
Luckily, the voltage immediately rose to more than 34 volts, clearly indicating a bad voltage regulator. Being able to diagnose this ourselves saved a minimum of an hours labor at a shop in addition to the cost and inconvenience of driving there. There's also the possibility of a service shop simply recommending the replacement of both the alternator and the regulator without even bothering to perform this test.
A new alternator is $1,300 - $1,400 with a re-conditioned one at about $900.
My replacement voltage regulator cost less than $200.
Fired up the bus and all is well again !!:D!!
By relying on a fellow POG member to help me diagnose this problem saved me much more than the cost of POG membership. And, there's the added benefit of having a diagnosis that can be relied upon as opposed to simply changing parts.
Thanks Jon !!
Without question, POG membership pays.
A couple of days ago, I started up the coach and sure enough, the dash warning light came on again...... and stayed on. Checking the voltage meter, it was clear that the alternator wasn't charging the chassis batteries. A quick PM once again to Jon and he gave me the good and bad news.... it was either the alternator or the voltage regulator. I was sure that a new alternator was in my future, since I had already replaced the 12 volt house battery alternator last year.
Jon gave me clear instructions as to how to diagnose the problem. Check the battery voltage with the engine running. Now, jumper between the "field" terminal and the "positive" terminal on the voltage regulator. If the voltage stays the same, a bad alternator is indicated. However, if the voltage rises, a bad voltage regulator is the culprit.
I hooked up the multi-meter and convinced Janice that she should be the one to hold the jumper wire between the two terminals on the regulator, as only a trained professional could interpret the meter readings and besides, she has curly hair already :eek:
Luckily, the voltage immediately rose to more than 34 volts, clearly indicating a bad voltage regulator. Being able to diagnose this ourselves saved a minimum of an hours labor at a shop in addition to the cost and inconvenience of driving there. There's also the possibility of a service shop simply recommending the replacement of both the alternator and the regulator without even bothering to perform this test.
A new alternator is $1,300 - $1,400 with a re-conditioned one at about $900.
My replacement voltage regulator cost less than $200.
Fired up the bus and all is well again !!:D!!
By relying on a fellow POG member to help me diagnose this problem saved me much more than the cost of POG membership. And, there's the added benefit of having a diagnosis that can be relied upon as opposed to simply changing parts.
Thanks Jon !!
Without question, POG membership pays.