Changing valve seals using air chuck: If I have air leaks are the heads toast?

[WorkinLonghorn]

I agree with above. You probably don't want to hear this now that you've finished the seal job but I always hear (from machinists) that a motor with shot valve seals usually is in need of guide work anyway. If this was mine,I woulda taken the heads off and de-carboned etc.

[thecatseye66]

I finished up the seals about ten minutes ago. No problems at all once I learned to "seat" the valves by putting a block of wood against the valve spring assembly and give them a couple wacks before I took each one apart. I would just hook up the air after bringing each cylinder to TDC, then take off the rockers and give them a smack if there was air coming out of the exhaust or intake port. Once they seated I just tore them down and moved to the next.

I know a couple of you guys said I should do more teardown, but this motor is really clean. It is an original 45,000 mile 396 that came with a 2-barrel and was never driven hard. There is no sludge or carbon buildup anywhere--there were just a bunch of hardened and broken valve seals on the exhaust valves and it smoked a bit when I'd first start it up, but the compression is excellent. The motor had never even been out of the truck.

I'm putting in a new oil pump and I already put on a new timing chain and gears as well. I'm putting on an aluminum high-flow water pump and a quadrajet too. I picked up an original '68 q-jet high rise at a swap meet so it'll all look bone stock again when I'm done.

Thanks again for your input guys--