tlicitra
Member
I recently completed a restoration on a '73 fastback for my son. His first car. We pulled the motor during the process but didn't rebuild it as it ran O.K. (No smoking, compression in the 132-151 range, stock motor, about 90,000 miles. Never rebuilt that I know of.) The car ran even a little better after we put it back in. (rebuilt the 2 barrel motorcraft carb, new timing chains, pulled the valve covers and cleaned out what we could get to, swapped the manifolds over to 4 barrel manifolds.
Last week the car didn't want to turn over. It would crank, but spit and sputter like it wasn't getting gas. Checked the fuel pump, and changed the fuel filter, no issues there. Pulled the plugs and not surprisingly they were fouled. (The distributor is stuck in the block and is in a slightly advanced position, another future fix). I was getting a little white smoke, so I though maybe the head gasket blew. Here's where things got interesting.
I pumped 120psi into each cylinder to see if any air would bubble up through the radiator fluid to see if the head gaskets were bad. No bubbles. But during the test on some cylinders I had air blowing out of the carb, and on others had air blowing out through the breather on the valve cover. I read that air coming out of the carb indicates a valve job is needed on the head, and that if air comes out of the breather it indicates badly damaged rings and pistons. TRUE?
I did a second compression test and I'm still in the 132-151 range, so I'm not thinking it's a head gasket. I cleaned and replaced the fouled plugs, leaned out the carb a little and got it running again, but it has never run as well as I thought a 351C should. Am I looking at a rebuild here? Any other suggestions on what I might want to check? Thanks all!!!
Last week the car didn't want to turn over. It would crank, but spit and sputter like it wasn't getting gas. Checked the fuel pump, and changed the fuel filter, no issues there. Pulled the plugs and not surprisingly they were fouled. (The distributor is stuck in the block and is in a slightly advanced position, another future fix). I was getting a little white smoke, so I though maybe the head gasket blew. Here's where things got interesting.
I pumped 120psi into each cylinder to see if any air would bubble up through the radiator fluid to see if the head gaskets were bad. No bubbles. But during the test on some cylinders I had air blowing out of the carb, and on others had air blowing out through the breather on the valve cover. I read that air coming out of the carb indicates a valve job is needed on the head, and that if air comes out of the breather it indicates badly damaged rings and pistons. TRUE?
I did a second compression test and I'm still in the 132-151 range, so I'm not thinking it's a head gasket. I cleaned and replaced the fouled plugs, leaned out the carb a little and got it running again, but it has never run as well as I thought a 351C should. Am I looking at a rebuild here? Any other suggestions on what I might want to check? Thanks all!!!