Cricket Too
Lieutenant Commander
- Joined
- May 14, 2003
- Messages
- 1,732
After a bunch of rain earlier in the week and the bilge pump running probably non stop for hours on end (13' Whaler), I went to go out last night and the battery was dead..or just about. It had enough left in it to just barely crank the engine over enough, the engine fires off with barely a turn almost every time so the battery had just enough left in it. Didn't think the battery should be that dead after rain so I figured maybe it hadn't been getting charged by the engine.
Grabbed my meter just to check things out and the battery was at 10.4V...so it was drained bad. Started the engine up again....just barely again and put the meter back on and still showed 10.4, took it up to about 2200 RPM in neutral and charging voltage didn't move a bit. I swapped out the battery with a good, fully charged one and started the engine back up, threw the meter on and it read 12.6, never went up at all. Brought the engine up to 2200 in neutral again and no change in voltage. Just want to add that the tach is working, hence me knowing the RPM I'm bringing it up to.
I know these little engines don't put out much charging amperage, but I figure I should still be seeing at least 12.9 - 13.2V or so when it's running at idle right, or at least at 2200 no? Do these little engines just basically use the battery for starting and not put out much for charging at all? I'm pretty sure that once started the stator provides all the engine needs to keep running....thus not sucking the battery dry like a car would do if an alternator gave out, correct? I don't expect it to charge a dead battery, I know they're not meant to do that, but 12.5 or 12.6V at 2200 RPM seems like zero charging to me.
I've been reading around on the test procedure to check the reg/rec and then it occurred to me that this might be an unregulated charging system and a weak battery might have fried the rectifier. The battery is not new, in fact it's old, about 6yrs old. I know, I know I should've changed it out but just kept putting it off.
Anyway I found a post that Joe Reeves made on another site, it's probably on here too but Google found this first. It's got some weird symbols all over it, I think I have the jist of it, but just wanted to ask if I should see any specific readings when I hook the meter up or if it doesn't matter as long as you get some kind of reading in one direction and no reading the other? My rectifier has the 4 wires, yellow, yellow/grey, yellow/blue and red.
Anyway here is a pic of the rectifier on my engine, not sure if it is a reg/rec or just a rectifier. Joe Reeves procedure is below too.
Remove the rectifier wires from the terminal block. Using a ohm meter, connect the black lead of the ohm meter to the rectifier base (ground), then one by one, connect the red lead of the ohm meter to the yellow, yellow/gray, then the red wire (some rectifiers may also have a fourth yellow/blue wire. If so connect to that also). Now, reverse the ohm meter leads and check those same wires again. You should get a reading in one direction, and none at all in the other direction.
Now, connect the black lead of the ohm meter to the red wire. One by one, connect the red lead of the ohm meter to the yellow, yellow/gray, and if present, the yellow/blue wire. Then reverse the leads, checking the wires again. Once more, you should get a reading in one direction and none in the other.
Note that the reading obtained from the red rectifier wire will be lower then what is obtained from the other wires.
Any deviation from the "Reading", "No Reading" as above indicates a faulty rectifier. Note that a rectifier will not tolerate reverse polarity. Simply touching the battery with the cables in the reverse order or hooking up a battery charger backwards will blow the diodes in the rectifier assy immediately."
Grabbed my meter just to check things out and the battery was at 10.4V...so it was drained bad. Started the engine up again....just barely again and put the meter back on and still showed 10.4, took it up to about 2200 RPM in neutral and charging voltage didn't move a bit. I swapped out the battery with a good, fully charged one and started the engine back up, threw the meter on and it read 12.6, never went up at all. Brought the engine up to 2200 in neutral again and no change in voltage. Just want to add that the tach is working, hence me knowing the RPM I'm bringing it up to.
I know these little engines don't put out much charging amperage, but I figure I should still be seeing at least 12.9 - 13.2V or so when it's running at idle right, or at least at 2200 no? Do these little engines just basically use the battery for starting and not put out much for charging at all? I'm pretty sure that once started the stator provides all the engine needs to keep running....thus not sucking the battery dry like a car would do if an alternator gave out, correct? I don't expect it to charge a dead battery, I know they're not meant to do that, but 12.5 or 12.6V at 2200 RPM seems like zero charging to me.
I've been reading around on the test procedure to check the reg/rec and then it occurred to me that this might be an unregulated charging system and a weak battery might have fried the rectifier. The battery is not new, in fact it's old, about 6yrs old. I know, I know I should've changed it out but just kept putting it off.
Anyway I found a post that Joe Reeves made on another site, it's probably on here too but Google found this first. It's got some weird symbols all over it, I think I have the jist of it, but just wanted to ask if I should see any specific readings when I hook the meter up or if it doesn't matter as long as you get some kind of reading in one direction and no reading the other? My rectifier has the 4 wires, yellow, yellow/grey, yellow/blue and red.
Anyway here is a pic of the rectifier on my engine, not sure if it is a reg/rec or just a rectifier. Joe Reeves procedure is below too.
Remove the rectifier wires from the terminal block. Using a ohm meter, connect the black lead of the ohm meter to the rectifier base (ground), then one by one, connect the red lead of the ohm meter to the yellow, yellow/gray, then the red wire (some rectifiers may also have a fourth yellow/blue wire. If so connect to that also). Now, reverse the ohm meter leads and check those same wires again. You should get a reading in one direction, and none at all in the other direction.
Now, connect the black lead of the ohm meter to the red wire. One by one, connect the red lead of the ohm meter to the yellow, yellow/gray, and if present, the yellow/blue wire. Then reverse the leads, checking the wires again. Once more, you should get a reading in one direction and none in the other.
Note that the reading obtained from the red rectifier wire will be lower then what is obtained from the other wires.
Any deviation from the "Reading", "No Reading" as above indicates a faulty rectifier. Note that a rectifier will not tolerate reverse polarity. Simply touching the battery with the cables in the reverse order or hooking up a battery charger backwards will blow the diodes in the rectifier assy immediately."
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