shreveportpb 14 Report post Posted March 5, 2010 we run off a 75 gallon tank, and when we run just off the tank we cant use any hydros or anything without bad vibrations and little to no water pressure. we have to hook up to the building water supply to do any type of work. this is very limiting. as a business owner you would know what versitility can do. any help would be appreciated. Share this post Link to post Share on other sites
HighTide 14 Report post Posted March 5, 2010 (edited) First thing please fill out your signature. Welcome to TGS as we like to know who we are talking to. First thing, check the inlet filter between your tank and pump and make sure its clean (take apart and put back together). Then make sure no air is getting into the system before going into your pump. If that is not the reason, check back as others will chime in. Edited March 5, 2010 by HighTide Share this post Link to post Share on other sites
John Orr 206 Report post Posted March 5, 2010 Are you running a direct or belt (or gear) drive machine? Direct drives do not draw very well due to the speed at which they spin. Share this post Link to post Share on other sites
Jerry 24 Report post Posted March 8, 2010 (edited) I get this call frequently.. and the most common answer.. The Thermal relief valve was not designed to seal against a vacuum.. As the pump tries to suck water from the water tank.. the thermal sucks air.. IF your bypass line is run to the tank, you can remove the thermal for good. If you usually pressure-feed, and want both options.. put a strip of duct-tape across the thermal's outlet port, as a quick-fix, and go to my website for how to plumb a system with "Alternate-Source Valve" the image to see is marked.. "Tank Feed SCG w/reel" I also have to add.. Usually the working pressure goes down a little, not gone completely.. Whilst yer on the website, look at the big filters, and BIG feed-lines we use.. your pump-seals will last a LOT longer if the pump can never cavitate.. even if it's direct drive. give it the "perfect" water supply. call with any (and every) question. Edited March 8, 2010 by Jerry Share this post Link to post Share on other sites
MeiersEnterprises 14 Report post Posted March 17, 2010 Your feed line from tank to pressure washer is probably not large enough. For an 11hp 4000 psi direct drive machine you will need at least a 1inch inside diameter feed line (depending on length of feed line). For belt drive, you will probably need 1.5inches. Hope this helps Share this post Link to post Share on other sites
Joe Ortiz 14 Report post Posted March 18, 2010 +10 jerry 11hp prob 3-4 gpm 3/4" hose should work good. but if its sputtering you are getting air in the line. Share this post Link to post Share on other sites
Jerry 24 Report post Posted March 23, 2010 (edited) Sputtering-pressure is a "dead-give-away" there's an air leak. 3/4" feed line is "O.K" for 4gpm, for up to 5 feet from the tank, 1" line is insurance. Edited March 23, 2010 by Jerry Share this post Link to post Share on other sites