Hi, I am 19 and have a 71 3/4 ton 4x4 truck. The engine is a 360 and I do not know any of the history on it. I found a rebuild tag on the engine and it has been bore 0.40 and the crank has been turned 0.10 and the rods 0.10. I bought the truck for 200 dollars and it was sitting out in the weeds for along time. I swaped the body and box on it with a 69 truck and now I have it all put back together and now it does not seem to run well. It ran really nice when I first got it running. I have put new points, condencer and cap and rotor in it as well as a new coil, plug wires, plugs and an rebuilt autolite 2bl carb and fuel filter. I have had the valve covers off to make sure everything looked fine inside the engine. And changed the oil and ran a quart of tranny fluid thru it to clean it up inside. Here is my problem, I will start the it up and it will run really rough like it has a miss. I will run it for a little bit in different rpm ranges and it seems to smooth out somewhat when the rpms are up. once I shut it off it starts smoking out of the valve cover gromets and carb. It seems like the crankcase is pressuring up or something. I thought maybe it was a stuck lifter or valve but I checked and all is fine. I am going to be doing a compression test tomorrow. I dont know what is wrong with the thing it ran really great before. You have to hold the gas pedel to the floor for a while just to get it to start now. Does anyone have any idea what might be wrong? Are some of my rings collapesed or do I have a hole in one of my pistons? Or is it just something I am overlooking that is simple? Any help would be greatly appreciated.

Thanks,

Matt

 

Your carb is flooding or your ignition is not getting enough juice at idle. Mine did the same thing. I would put your old coil back on and give it a shot. A hotter coil and pertronix made mine a lot better. You may also have a leak in the carb or a bad float adjustment. If you think the crankcase is pressurizing take your oilcap off while it is running and see if that helps.

Also, check your timing. It may be too retarded.