318 valve seals

[John Reddie]

I have a "67 Fury III with a 1976 318 engine. I notice when I start it after several days of not running it there is noticeable blue coming out of the tailpipe. After a few minutes of running it seems to pretty much stop. The engine although it has high mileage (200.000 +), runs very well with good oil pressure and moderate oil consumption.
I know that sometimes changing the umbrella type valve seals can help this situation as the original seals over time can become hard and fail to seal properly. I am a little leery to try this change because sometime back I had a 1962 Dodge Dart with the slant six engine that would put out a small amount of blue smoke after leaving a stop light or at first start. I replaced the seals using a threaded air chuck in the spark plug holes to hold up the valves ( I have heard of people using nylon rope in place of air too).
I don't know what I did wrong but afterwards the car smoked so badly that I couldn't drive it. It fouled every spark plug and used 2 quarts of oil in 60 miles. I couldn't see behind me. I don't want this to happen to this car. Any thoughts and info here are welcome and most appreciated. Thanks
John R

 

[CBODY67]

Just as with the tailshaft seal on a transmission, when the inner bushing (wear surface for the slip yoke) wears, the slip yoke can move around and the result is that the seal gets wallered-out and starts to leak. Same thing with valve seals, when the guides and valve stems wear, the valve can move around and will waller-out the hole in the seal. In each case, replacing just the seal is a short-term fix, until the new seals get wallered-out too.

As long as you can tolerate the smoke, save money and plan on a valve job at sometime in the future. New bronze helicoil guides and new valves, with OEM-spec valve seals in the mix, too.

Maybe one notch heavier viscosity motor oil might help? As in 10W-40 rather than 10W-30, in the mean time?

Just some thoughts,
CBODY67

 

[413]

Using the air to hold up the valves can be bad on rings on a high mile engine. Use a rope .

I would just keep driving it like it is.