I've always kept the jump vehicle's revs around 1500-2000rpm. I couldn't give you an electrically competent answer as to why, just something that was ingrained at an early age.
88 XJ, millions of miles......
Posts: 139 | Location: Colorado Springs, CO | Registered: September 26, 2003
At idle, your alternator is not putting out the max it can, so the load is being placed on the battery of the running vehicle. When you rev the engine some, the alternator assists in getting the dead vehicles battery charged up enough to support the load of the starter. That's why many folks use throttle controls for winching, to up the alternator output during the heavy load during the winching and the battery recharging afterwards.
To boldly go where we're too stupid to know any better.
"Use your hammer, not your mouth, jackass!" Mike Ditka
Mostly 03 TJ, RE 4.5 Superflex, 35 x 12.5 BFGs, OBA, MM Hyd winch, Elockers, Custom built Dana 44's, Rockhard cage, and wonder gadgets.
