Marc,
I don't think the pump mentioned will do the job for a 2" dredge, the pump for my 2" does 100 gals a minute, your electric pump equate to approx. 42 gals per minute, also a dredge needs pressure to create the suction, my pump for my 2" does around 75 to 90 PSI and has around 160 ft. of head pressure, I don't think you are going to find an electric pump that will run off a battery that will come close to the volume and pressure you will need for 2" dredge.
A guy did post on the old forum a year or so ago a 1" electric dredge with a very small sluice box that he built, and it ran off a small 12v electric utility pump he got from Harbor Freight that had 50 PSI, I don't remember the volume, but he said it seems to be the only pump that he could find that had the right specs and would run for a couple of hours and work with his 1" small dredge, the entire setup beside the battery and some of the hose would fit in a 5 gal bucket, it also seems to be very hard to find the same pump after his posting as it seems to have been discontinued, Harbor Freight does still sell a pump that looks just like the one he was using but the PSI for this pump is only 10 PSI and that is not enough even for the small dredge he made.
This is the pump that only has 10 PSI...
http://www.harborfreight.com/cpi/ctaf/d ... umber=9576 You would have to search the old site for the post, I think I have pictures of the dredge and pump on my computer, if I can find them I will post the pictures that I copied (I got his permission to copy the pictures) from his post.
Skip
Skip P.
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