Does anybody have any experience with larger alternators on their trucks and having issues with the glow plugs staying on? I found this in the software and was wondering if anybody who has an alternator with higher output and a voltage setpoint above 14v has had issues with the truck smoking while running cold. See the table below... glow plugs turn off at 14V
Problems With Bigger Alternators
- Thread starter Gearhead
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jschildm
Member
It's actually very interesting that you mention this because I have put a high amp alternator on my '97 7.3 (I am not sure which motor you are talking about) and ever since then there his been a pulsing voltage from what I assumed was the glow plugs cycling off and on for a period after starting. I assumed glow plugs because after about a minute and a half or two minutes (when its cold out) it stops doing it and functions normally. The needle moves quite a bit, and there is an audible difference in the motor from the load. I will see if I can get a video of it sometime this weekend.
ghohouston
Active member
I had a 270 georgia power systems alt on my 2002, and had no problems with anything at all.
Yep... does your alternator run more than 14v? Im working on a solution to keep the voltage at say 12.5v until the glow plugs turn off then run full voltage.
jschildm
Member
I know it does over idle. It might be close at idle while the glow plugs are on(though I believe it still does it, if my memory serves me). It would be nice if they had a voltmeter in the dash on these trucks that would actually read an accurate instantaneous voltage.
Well I can tell you for a fact that the superduties are programmed to turn off above 14v for some reason. I've changed it for someone before, but I wonder if it is good for the glow plugs to operate them at that high of a voltage.
jschildm
Member
I would guess it was done to limit the current through the glow plug system. Especially since there are already issues with melting wires and connectors as it is. What kind of solution are you looking at?
I got a really poor quality video today, so I will see if its worth posting or not. I do have your tunes on my truck, if that makes any difference.
I got a really poor quality video today, so I will see if its worth posting or not. I do have your tunes on my truck, if that makes any difference.
jschildm
Member
jschildm
Member
I thought I edited out some of the shaking and not looking at the gauge, but you get the idea.
If anything it should be better for them because they will be required to pull less amps at the higher voltage. The glow plugs are rated in watts anyway, no amps
So that being said the higher the voltage the better it is on the wiring and the relay
But they have a constant resistance. More voltage more wattage. But resistance does go up when they get hot to some extent so wattage starts to taper off.
