?? open v. - complete v. , how much drop??

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I'm trying to get an idea of how much voltage drop one would usually see on a   feeders voltmeter from the time right before an arc is started and once arc is started, when using a engine driven cv power source.     In other words, It would be nice to hear from different people what type of portable machine you have and how much drop you see from open circuit to complete circuit.      I've never owned a portable machine that has cv output.     I've been trying out some SAM 400s from a welding company that has them for sale.     I've hooked up an ln-25 w/ some innershield wire  to them and am seeing quite a drop in voltage when once weld is started.    Machine #1 drops from 32v to about 25v once arc is started ( diff of 7v ).    If I have it set at 23v when ocv, it will drop to 18v when welding starts ( diff of 5v ).     The rest of the machines have about double the drop or slightly more ( 10 - 15v in droppage ).     These SAM 400s also have the capability to weld in constant current also.   So when I stick weld w/ them, upon striking an arc I have a hot start, but the rod wants to stick after a half a second.     If I can manage to keep the rod from sticking and keep the arc going, after about two and a half seconds into it, the arc will restrengthen itself, and I can burn the remainder of the rod w/o any problems.    So CC mode it falls after the hot start, and slowly climbs back up, in CV mode it falls and doesnt climb at all- it just maintains the instant drop.     Well I know I'm probally looking at some worn out machines here, but maybe one or two of them might last a little while longer.    Anyway I wouldn't mine hearing from different people what type of symptoms they've encountered shortly before there machines became junk or burned up, or possibly anyone whos had experince w/ these SAMs.
Reply:Maybe Im rambling on to much on that first post.     Can anyone tell me what kind of drop they see in voltage wire feeding on a engine driven cv power source once a load is put on.    In other words if  your machine is tacked up and right before you pull the trigger to weld you look at the voltmeter on your feeder ( we'll call that "Open Circuit Volts"), then you pull the trigger and start to weld, while welding you turn your head and look back at the voltmeter on your LN-25 or whatever feeder your using( we'll call that "Weld Volts" or "Comleted Circuit Volts").      Can anyone tell me how much drop they see, or the difference in volts between open circuit volts and weld volts.
Reply:Hey, I see what you are getting at, but I cant tell you how much drop I have on my SAM, or my 55G for that matter, either.  I dial my welder in by feeling the burn.  Sounds like you need to adjust the upper and lower left hand control dials that dials in the burn for various welding positions both stick and wire.  For the top, or stick, I would turn it all the way clockwise, then back about 60 degrees, maybe 90 degrees.  Also, try dialing your field control up and down, see if the burn issues change.  One thing you didnt mention, is that when you strike the arc, and it drops off, what is the engine doing?  What engines do these have?  If diesel, even if they had speed droop, they oughta have enough horses to pull through a big arc no matter.  Gassers, when they droop under a load they dont ever seem to have enough horse to pull through a heavy arc, esp. when there is governor issues.  How many are there, and how tired are they, really?  Engines to stay far, far away from on SAMs are the GM Bedford diesels.  They were some kind of english made junk, I have only seen two of them, both were very low hours, with holes in the side of the blocks.  I would think anything with hours, would have detroits or perkins.  Anyway, hope that helps a little.cc