12V charging delay?
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From: Paradise, CA
12V charging delay?
Monitoring my voltmeter, I see that there's always a delay (haven't timed it... maybe 10 seconds) before charging starts. Everything else appears normal, and this is my first SD. Is this delay normal?
Phil
'03 F250 7.3L SC 2WD
Phil
'03 F250 7.3L SC 2WD
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From: Long Island USA
That doesn't sound normal - it's a "self-energizing" alternator, or should be. Which means, it will go into charge without needing any outside voltage to get the alternator to start charging. Older stuff needed even a slight outside voltage supply to kick start the stator.
However, the PCM for the 6.0's (I think) controls the alternator - does it do it for the 7.3 too? Guys?
However, the PCM for the 6.0's (I think) controls the alternator - does it do it for the 7.3 too? Guys?
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From: Paradise, CA
I timed it at 20 seconds on a cold start before it started to charge. Subsequent starts the rest of the day the charging was immediate. But the way it's delayed made me think it may be controlled by the PCM. 2003 was when the 6.0s started production so maybe they were gearing up for them early in the production run while they were still installing the 7.3s?
The batteries, while only 6 months old, weren't very good.... drive for an hour, check batteries an hour after parking and the reading would be 12.47 (Fluke at battery posts). Before starting, after the glow plugs warmed, the voltage would read 11.2 (Edge Evo gauge on dash). I put two new good batteries (850cca) in over the weekend to replace the made-in-mexico 650cca pair. Now after the glow plugs and before starting it's reading 11.9 or 12.0 and the engine cranks and starts noticeably faster.
It looks to be the original alternator with 100K on the odo.
But I forgot to monitor the voltmeter to see if the charging delay is still there or not. On my to-do list now.
Phil
'03 F250 7.3L SC 2WD
The batteries, while only 6 months old, weren't very good.... drive for an hour, check batteries an hour after parking and the reading would be 12.47 (Fluke at battery posts). Before starting, after the glow plugs warmed, the voltage would read 11.2 (Edge Evo gauge on dash). I put two new good batteries (850cca) in over the weekend to replace the made-in-mexico 650cca pair. Now after the glow plugs and before starting it's reading 11.9 or 12.0 and the engine cranks and starts noticeably faster.
It looks to be the original alternator with 100K on the odo.
But I forgot to monitor the voltmeter to see if the charging delay is still there or not. On my to-do list now.
Phil
'03 F250 7.3L SC 2WD
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From: Patricia, Alberta
That charging delay cost me a lot of money when I was buying a truck at an auction. The yard apes would boost the trucks, wait a few seconds, then take the cables off, and the trucks would die. (All '05 and 06's and they all had totally dead batteries) I let a few go, thinking there was something wrong with them, then I figured it out near the end of the auction and paid a few thousand more than they'd been going for earlier. I don't know what the delay was, but it seemed like it was a minute before they could take the cables off and they'd stay running.
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From: Paradise, CA
I did some further checking after work yesterday:
New batteries didn't change the delay. It's still about 20 seconds ( "Mississippi" counted, not using a stopwatch, could be 30). An hour later, the same delay. Very consistent, which is why I started the thread.
Increasing the RPMs during the delay does nothing, unlike alternators "on the edge" of years past which would suddenly start charging when the engine was 'gunned'.
I also verified the voltage readings on the EVO with my Fluke 88. The EVO reads ~.02v high, which is acceptable since the EVO only reads to 1/10th volt and one reading was at the driver's battery posts and the other from the OBDII connector.
John's post further leads me to believe it's a programmed delay.
Phil
'03 F250 7.3L SC 2WD
New batteries didn't change the delay. It's still about 20 seconds ( "Mississippi" counted, not using a stopwatch, could be 30). An hour later, the same delay. Very consistent, which is why I started the thread.
Increasing the RPMs during the delay does nothing, unlike alternators "on the edge" of years past which would suddenly start charging when the engine was 'gunned'.
I also verified the voltage readings on the EVO with my Fluke 88. The EVO reads ~.02v high, which is acceptable since the EVO only reads to 1/10th volt and one reading was at the driver's battery posts and the other from the OBDII connector.
John's post further leads me to believe it's a programmed delay.
Phil
'03 F250 7.3L SC 2WD
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