Hello: I have a 1993 7.3 engine and have been experiencing the following problems.
1-While driving normally at operating temp the alternator guage drops down and the wait to start light comes on ..After a few seconds this goes away and everything is normal.This was about Dec 15

2-After changing 2 burnt glow plugs everything was ok until Jan 1. Started truck in morning -18C..no problem to start (took about 20 seconds for light to go out)..warmed up for a few minutes and was off.
Went about 1/2 mile and alternator/shut down occured again and once again was gone in a few seconds..Truck worked fine for the next 3 days and then in a 6 hour period the problem occured 7 times. Sometimes the "wait to start" light did not come on. Thinking that the only item that draws so much power is the glow plug relay I ordered a new one and replaced the unit. Wait to start light now was down to 4 seconds and the truck would not start if not plugged in at -10C.

3-Checked the glow plugs and found that 2 more had burnt out...probably caused by the module turning the plugs on while the truck was warm and running. Replaced the plugs and now the wait to start light goes out approx 10-12 seconds which is normal (i think) and the truck starts right away with no "missing".

4-The "new" problem is that with all parts replaced something caused the "alternator to shut down" or cycle for a split second. It happened so fast that I was not able to tell if the lights stayed on or not...everything went back to normal very quickly. This has happened 2 times and only (so far) when the engine was "cold" ie 2-3 minutes after starting.

My question is ..has this happened to anyone else and what was the resolution or does anybody have any suggestions/ideas what is wrong..or is it considered "normal" for this to happen when the engine is cold..This had never happened before since I have owned the unit ...4 years.

Thank you for any help.

Kodie

 

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Kodie check out the post by Scottie on this page........

Questions.. does your volt meter drop down when the gps/ignition is turned on, it should. Does the voltmeter swing back and forth when the gp are cycling after the WTS light is out, it should.

If you are seeing a red light from the alternator I would think your brushes or regulator are the cause. Try running the engine at 2000 rpm and putting a voltmeter across the neg and pos posts you should see about 14+ volts, wiggle some wires on the reg/alt see if voltage moves. There is one small wire that is known to have connection troubles and burns out at the connector on the alt.