I have an older Clark LPG lift from the 60's or 70's I'd guess. The ID tag was painted over then someone took a grinder to remove the paint! Pure genius I know! But this morning it didn't want to start and cranked over really slow. I checked starter and battery and all connections and everything was fine but she still cranked really slow. Then I pulled back on the lift lever while trying to start and she cranked over fine and fired right up! But as soon as I let go of the lift lever the forklift died! If a lever is being operated, tilt or lift up or down it runs great, however, as soon as you release the lever it dies! Its like the bypass or priority valve isn't working? Do these even have priority valves? Any ideas what to look for? Worked fine Friday now this morning having this problem! Thanks!