Compression Ignition Addict
Join Date: Dec 2007
Thanked 249 Times in 240 Posts
Mentioned: 6 Post(s)
Quoted: 90 Post(s)
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I would be thinking you have a problem with either getting the current you should TO the Starter OR the starter is requiring more current than it should and only the, added, booster pak makes enough available.
So, the cables and ends (ALL of them, Both sides & polarity) need to be scraped clean, greased, & tightened or replaced (if needed).
Then, if the batteries are all they are supposed to be (maybe have them Load Tested, at a high rate to be sure), I'd be thinking the Starter is just weak. Did it do this before you replaced it?
Have you monitored the Voltage as you're cranking? What is it dropping down to?