grizzley 14 Report post Posted September 13, 2006 I am getting ready to replace an unloader on a Landra PGDC and after reading several opinions, I am thinking about the Zk1 since it is flow and will be easier on the entire system. I have a HydroTec that has a flow unloader and it is TOUCHY. At times, it won't flow ANYTHING, but other times it flows max pressure within 2-3 seconds. Hopefully this isn't normal to be so sensitive. As far as flow unloaders, is the Zk1 one of the best ones? I have found them for $57.55 (new with warranty); is there a better place to buy them? Share this post Link to post Share on other sites
Dan Stapleton 14 Report post Posted September 13, 2006 First off, where at that price? I've heard good things about them. I know of people who have switched to them and have had no problems. Let us know. Share this post Link to post Share on other sites
grizzley 14 Report post Posted September 27, 2006 I got to looking and it looks like the Zk1 is only rated to 3800 PSI. Is this correct? Share this post Link to post Share on other sites
Washaway 64 Report post Posted September 28, 2006 I'd also like to know where you're getting them at that price. I'm dishing out over $110/ unloader. Share this post Link to post Share on other sites
Russ Johnson 141 Report post Posted September 28, 2006 Chris, Your Hydro Tek probably has a K7 on it... here's a little trick. Remove the bottom cover ( 13 mm head bolts), pull the piston out, and remove the spring underneath. Stretch the spring a little, but evenly. Grease the rubber cup on the piston and reassemble it. Should hit every time. Share this post Link to post Share on other sites
usarose 18 Report post Posted October 6, 2006 Chris,Your Hydro Tek probably has a K7 on it... here's a little trick. Remove the bottom cover ( 13 mm head bolts), pull the piston out, and remove the spring underneath. Stretch the spring a little, but evenly. Grease the rubber cup on the piston and reassemble it. Should hit every time. Rus Please tell me why you suggest this? Is it for the K7 only? I have just purchased some ZK1's - for my trailer mounted washer. I also have a 3000psi cold water (faucet fed) Shark mobile unit with a belt driven general pump - can I fit a ZK1 to that unit as well? Rob Share this post Link to post Share on other sites
Russ Johnson 141 Report post Posted October 6, 2006 Stretching the spring increases the closing pressure of the bypass valve (nothing to do with operating pressure), snapping it closed faster when the flow starts. The ZK1 is a completely different design. It does not have this spring in it. Share this post Link to post Share on other sites
