desertdeals69 Report post Posted October 6, 2016 I just started working on a new to me 98 Discovery. Air would leak down in less than an hour. I was airing the system up with my shop compressor and when I disconnected the airline air came out. The check valve at the drier was stuck open. I replaced it then the purge valve in the dryer had a small leak. The air in the tanks leaked back to the drier so I changed the valves at each tank. Now it holds pressure. Share this post Link to post Share on other sites
wolfe10 Report post Posted October 6, 2016 Wonder if the dryer was WAY past due for servicing. Maybe water or worse filter media got in the system-- can certainly contaminate the check valves. Look forward to hearing what you find in the wet tank drain. Good luck with it. Share this post Link to post Share on other sites
desertdeals69 Report post Posted October 6, 2016 I'm sure the dryer is way past due for service. When I drained the tanks they were dry. I have the service kit for the dryer. Share this post Link to post Share on other sites
