Generator Over-charging ??

[stevenelle]

Battery has been giving less and less cranking power over past week and a few times failed to start B2B. Discovered that battery had less than 50% fluid as normal. Added water and Ok for now. But a guy in church said that the generator may be over-charging the battery causing the water to boil out. He says voltage regulator can be adjusted to compensate for this. Has anyone had an experience similar to this and if so, what did you to to fix it. I did put a different generator on it from a parts truck about 4 months ago. Thanks for any insight.

[JBNeal]

I was told waaay back to take an emery board & clean the contacts in the regulator. When I checked my contacts, they were dirty and looked to have been sticking as evidence of some charring. After cleaning the contacts, I could clearly hear the contacts opening & closing at idle & when coasting to a stop. Simultaneously, the amp gauge showed when the generator was sending current to the battery. My guess is that your contacts are sticking instead of vibrating while driving.

btw There is an entire section in the shop manual on checking & adjusting the circuit breaker and voltage & current regulators. I made a small adjustment on the current regulator after cleaning the contacts, and it seemed like the battery was able to keep a consistent voltage and I didn't need to top off the cells every month or so.

[greg g]

Don't use an emory board, use a points file. What is your ammeter showig? A properly operating system shoud show minimal charge rate after the generator puts back what was used for starting.

If your meter is howing a constant positive charge rate of 20 or more, you could be cooking the battery. You can also be overheating the generator, which in extreme cases can melt and spin out the solder. What happens to the indicator when you are running doen the road with the headlights on? If the gauge drpos withthe lights on it idicates that the VR probably needs attention or replacement.

[stevenelle]

Thanks to both of you for this simple advice. I did check the points in the voltage regulator it did appear that one set were burned. I filed them a bit and now the ammeter shows a more normal rate of charge. Before, when they were stuck together, it was charging to the far right +50 nearly all the time. Another example of the good practical advice on this forum. Thank you

[HanksB3B]

Does anyone know what the "Vital Signs" of our trucks are meaning:

1. Fuel Pressure

2. Generator output at 450 rpm and at throttle up

3. Vacumme Pressure at the manifold plug.

4. Timing is 4deg TDC right?

5. Oil Pressure at idle and at running speed

6. What else is there?

It's probably in the book but after I read 15 is too young 36 is too old and 24 is just right for firing order (153624), I figure someone has it memorized.

Feeling Lazy and Tired,

Hank

Edited February 16, 2010 by HanksB3B

[greg g]

FP is 4 to 7 lbs

Gen output is 6.7 to 7.1 volts 20 to 25 amps max depending on battery state

vacuum is 19 to 21 inches steady

timing is TDc to 6 BTDC depending on model year application and distributor number

oil pressure hot at idle should be negligable to 20 and at speed should be 10# /10mph

to a max of 45/50

A properly flowing radiator should raise a column of water from the lower hose connection when relased from full of apx 6 inches in height.

fuel flow should yield 8 to 10 ounces of fuel per 12 pulses of the fuel pump

Coolant should cover the the cooling channels by 1/2 to 1 inch within the top tank of the radiator. Over filled coolant will puke itself out and should be left at whatever level it naturally reaches after a temp cycle. Normal operating temp should be between 160 and 200 degrees on a non presurized system depending on the thermostat installed.

[HanksB3B]

Thanks. Today I'm on my way to a shop that is supposed to be really good. Now that my trucks together and running pretty well I want to "dial it in"

this will help. I'll print it out.

I appreciate it!

Hank