| Author | Message | ||
| Jack Conrad (Jackconrad)
Registered Member Username: Jackconrad Post Number: 1277 Registered: 12-2000 Posted From: 67.142.168.139  Rating: N/A |
Yesterday while driving to Palmetto Cove, I noticed our 12 volt voltmeter (house batteries) bouncing between 14 and 15.5 volts. I pulled over and removed the belt sow e could continue to the Cove. House bank is 8 6 volt golf cart batteries that were topped off, cleaned, reinstalled, and all connections cleaned and tightened just before this trip began (3/5). The alternator is a 1 wire auto type alternator. My question is, does this sound like the regulator that is built in the alternator has failed or is there another possible problem? I am going to stop by an Auto Zone, Pep Boys, etc. this morning to see if the regulator operation part of the alternator can be bench tested. Thanks in advance, Jack PS: I am posting this on both BBs to get more information | ||
| Buswarrior (Buswarrior)
Registered Member Username: Buswarrior Post Number: 1848 Registered: 12-2000 Posted From: 76.71.100.13  Rating: N/A |
My first suspicion would be the gauge, not the alternator. Try the multimeter and see? happy coaching! buswarrior | ||
| Jim Wilke (Jim Bob) (Pd41044039)
Registered Member Username: Pd41044039 Post Number: 468 Registered: 2-2001 Posted From: 184.0.3.170 Rating: N/A |
The little regulator can fail to full charge or to no charge. I'm with B/W to check the meter but I think it'll be the reg. Now I think that if the wire between the alt & the batteries is open or has a lot of resistance, the reg can't sense the batteries and may go to full output. Hopefully there is no battery isolator between alternator & batts, either. With engine off, check the voltage at the alternator output stud to be sure it is the same as at the battery end. | ||
| George M. Todd (George_todd)
Registered Member Username: George_todd Post Number: 994 Registered: 8-2006 Posted From: 64.55.111.6 Rating: N/A |
Some more thoughts: A 1 wire alternator does indeed use the voltage right at its output terminal for the reference. However, if there is excessive or intermittent resistance in the output wire to the batteries, the gauge on the batteries will read normal to low. With the engine running, and a good reg, voltage will always be 14.2 at the alt. An engine off reading will only verify that the wire is "there," because the voltage will always be the same when reading it with no current flowing. A connection could have loosened between March 5 and April 20? I feel its the regulator portion of the alternator, and my suggestion would be to take the alt to a rebuilder if there's one in the area. The rebuilders can test it too, and they know how to set up and read the tester. A counter guy in a chain store won't be able to find a listing for an MC8, and probably can't set the tester up properly without knowing the make and model of a car that your alt is used in. Belt up, fire up, and look at the house lights. If they're going brighter and dimmer, its the reg, or a connection, not the gauge. G (Message edited by George_todd on April 21, 2010) | ||
| Jack Conrad (Jackconrad)
Registered Member Username: Jackconrad Post Number: 1278 Registered: 12-2000 Posted From: 67.142.168.139 Rating: N/A |
Thanks for the information. I will recheck all the connections and battery cells today (it was raining when we arrived yesterday). With belt removed, the voltmeter stayed at 12.5 volts. With belt in place and volt meter jumping, the inverter panel sahowed a fault (high voltage). The alternator is a standard 1 wire type as used on automobiles, not a big MCI type unit. Jack | ||
| John Lacey (Junkman42)
Registered Member Username: Junkman42 Post Number: 119 Registered: 3-2007 Posted From: 66.82.9.11  Rating: N/A |
Jack if You can live without the alternator for a few days perhaps You can find a rebuilder where You are! It is unusual for a solid state regulator to be erratic, most likely a bad or broken connection in the alternator. Mark the case halfs and open up the alternator and have a look. If You are a person that knows how to work on alternators ignore Me! John L | ||
| George M. Todd (George_todd)
Registered Member Username: George_todd Post Number: 997 Registered: 8-2006 Posted From: 64.55.111.6 Rating: N/A |
There you go Jack, keeping us in the dark again! HA. Now that we know the gauge doesn't jump with the belt off, AND the inverter is complaining about high voltage with it on, no question about it, the regulator is baaad. (That's what the sheep said.) I was kidding about telling a counter person it was on an MC8, but serious about knowing what make and model of a car or pickup truck to tell them to set the tester for. At least at Auto Zone, they have to plug a module into the tester for the specific make and model, to make it work. I tried it with the alternator off our Toyota forklift, and after several modules, all of which read bad, I gave up and drove across town to a rebuilder to get a new one. I was going to have to get one that looked the same, because we couldn't match the part number. Putting it on a plain old tester, where you just had to read Amps thru a big resistor, and Volts, it put out 35 Amps at over 15 Volts. So, went back to look at wires, (no schematic,) and found a chafed wire, and a blown 10 Amp fuse up under the dash. G | ||
| Jack Conrad (Jackconrad)
Registered Member Username: Jackconrad Post Number: 1280 Registered: 12-2000 Posted From: 67.142.168.139 Rating: N/A |
When I bought it, I simply asked for a universal 1 wire alternator, no specific make or model. I think I will look for a local alternator/starter rebuild shop. Thanks, Jack (Message edited by JackConrad on April 21, 2010) | ||
| doug yes (Dougg)
Registered Member Username: Dougg Post Number: 129 Registered: 1-2007 Posted From: 162.40.209.63 Rating: N/A |
Just for my education, could you post a picture showing how you mounted the Alternator? I'm thinking of doing the same. | ||
| niles steckbauer (Niles500)
Registered Member Username: Niles500 Post Number: 963 Registered: 11-2004 Posted From: 173.78.39.41 Rating: N/A |
Jack - Are you going to be near Walhalla SC any time soon - Don't forget Gene Rochester has his shop there - HTH | ||
| George Martinez (Foohorse)
Registered Member Username: Foohorse Post Number: 93 Registered: 1-2010 Posted From: 174.48.6.180  Rating: N/A |
Jack if you get a story or the run around send it to me. I will set it right for you. parts cost only. | ||
| james dean boggs (Jd_boggs)
Registered Member Username: Jd_boggs Post Number: 156 Registered: 11-2004 Posted From: 76.83.200.109 Rating: N/A |
I had this same problem for years until I solved it last summer. Sometimes these buses have multiple wire segments joined together by pin and socket connectors. These connectors get dirty or the socket looses tension and you get the gage needle bouncing. You can experiment by installing a contiguous wire from the gage terminal to the source and see if that fixes it. In my bus 4 wire segments are common for the volt gage and the fuel tank gage. I solved both by running new contiguous wires. Hope this helps. |