Hello group,

I would appreciate some advice on the current situation. My 6 cyl - 603 - 300d in the morning has been acting up. Usually, the engine turns once over and starts right up after a 15 sec wait for glow plugs to heat up. The last few mornings ( cold !!!) and even afternoons when it is time to go home, I turn the key on and the engine barely truns over like there is not enough juice in the battery once the glow plugs are on. So, I took it last night to the Auto Zone and had the manager put the tester on it. The battery according to the tester is good, under load checks good. He tested the amp draw prior to start and during start and found that the glow plugs draw around 100 Amps and the starter around 165 Amps. Together as the car starts the overall draw is 268 Amps. That seems high. It also took the voltage of the battery down to 9.9 Volts.
Question: Is 100 Amps too much for the glow plugs draw ? Is there a problem there ? The starter draw seems also high. In my experience it should draw around 75 amps.
The alternator puts out 13.68 volts and 52 amps, that seems OK right ?
The battery is 2 years old, DuraLast 7 year warranty. They would not change it because it tests ok. I didn't put it on the charger yet but I will tonight.
Any suggestions ? Do I have a battery going bad or is the starter, glow plugs system drawing too much for the alternator to make up ?
Thanks.

Marius

That drawe does seem excessive although I will admit to knowing nothing about your engine.
The strip fuse for the glow plugs I think is only 80 amp so 100 seems weird that it would even measure that high. As tot eh starter I am prety sure that there should not be that much current draw when it is trying to turn. Could be that the starters beginning to go on you... Sorry.
You might also check all yoru connections especially the grounds. If you have a bad connection on a ground it will cause all kinds of problems.

__________________
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'78 Ski Nautique

If the voltage is low, the amperage will be higher.

Your alternator output sounds low--it should be doing 14.0-14.1 with a low battery. Try the charger for a while to get the battery back up and see if the alternator is still not putting out. With a charged battery & the alternator running, you should measure 14.0-14.1 volts at the battery.

Could be bad brushes in the alternator--a simple fix (at least on other models--not sure about the 124).