Ch25 no compression after HG replacement

I have a Scag TT with a ch25. The sticker with the engine spec nos is gone, but it's an older model, the first year they made the TT. Around 1600 hrs. I put around 50 hrs a year on it. I replaced the left side head gasket and now have no compression. Leak down test shows both valves leaking. Remove the rockers and most of the leakage is gone, so the valves are being held open. Is there a trick to getting the lifters to bleed down? It sat for a couple hrs with the rockers installed and it...

Ch25 no compression after HG replacement