Wrenchbender Ret.......Ok, the charging voltage is about 1/2 volt too high......is that over-charging the battery, and a bit too much, and harmful to the battery? I will do a load test on the battery to see if there may be a bad cell. However, when the truck sits for a few weeks, I will test the battery and she is maintaining about 12.5 volts. She has plenty of cranking power when she is cold, but the problem arises after she is warmed-up.
Sorry....I forgot to mention that this is the standard small block 307 V8, with a 2 barrell carb, headers, dual exhaust, and 3 on the tree. Still has the stock points/condensor (not electronic ignition). The battery cables are the good heavy duty ones, and have been on the truck the 25 years which I have owned her. (Kept clean and maintained at the battery posts. However, I have not removed the cables/wires at the solenoid/starter and cleaned in many years).
I will do the load test on the battery and let you know the results. However, why would the battery seem so powerful when cranking the cold engine, and then struggle and barely turn over the engine when warmed-up? I would think that the battery would have a bit more juice after charging for 15 minutes as opposed to a cold start with the battery down at around 12.5 volts.
I will also look at the starter and see if it is a high torque or standard. Again, the starter has been on the truck for over 25 years, and I never had this problem until recently.
Now I am thinking "valves". If the valves warm up and are not adjusted with enough clearance, then maybe the engine is cranking and an exhaust valve is not opening up to relieve pressure, making the engine hard to crank when warm? However, I thought that these 307s had hydraulic lifters, and never needed adjusting. Is this true?
Thanks for all the input.
