I bought an non-running pressure washer from Marketplace. The seller said it hadn't been running for a couple of years. Typically the gamble on these for me is whether the pump is shot, and if the pump is good I can flip by getting it running, and put it back on Marketplace. I can't get this one running! I have disassembled, cleaned, installed new seat and needle on the carb. After this failure, I installed a new, aftermarket carb. Also new air filter and added a fuel shutoff valve, and spark plug. The symptoms are staying the same, will only fire on choke with starter fluid, runs a couple of seconds, the governor goes back and forth a couple of times, then dies. I am also getting a lot of smoke during the few seconds of running. I have changed oil thinking there might have been gas in the oil but no change. I am assuming some deeper problems; I checked the compression and was getting 70psi after about 6 pulls. I was hoping that there was oil in the cylinder and I would be able to run it out but since I can't get it to run long enough to see if it will stop. I am assuming either a head gasket or bad rings/scored cylinder. My next step will be to pull the head (which will be a new experience for me). I guess my first question is whether the 70psi reading is enough to run this engine. If it was a bad head gasket, I think it would explain the smoke but would it explain the failure to start. Briggs 102Q802-0120 Thanks in advance!