5.7l tbi burning oil on driver side exhaust

[Mr.hillbilly]

So I have a 1990 k5 blazer with a 5.7l tbi and it has been running great until 2 weeks ago when it started burning oil from the drivers side exhaust. When I’m driving I don’t see any smoke coming out but when I let it idle for a minute it starts to smoke I also noticed that there is oil all over the back of the header dose anyone know what’s going on here?

 

[Wes Harden]

Welcome to CK5

The smoke is coming from tail pipe after idling? This would be valve guides/seals.
The oil on/from the header is dripping from connection, or on the out side?
If on outside check valve cover gaskets for leaks.
If when you have the valve cover off, be sure to check the oil drain back holes. If oil can't drain back well it could over whelm the guide seals and leak from cover seam.

 

[Mr.hillbilly]

Yeah I’m pretty sure my valve cover gasket needs to be replaced. I just took a look at it and it looks like it’s coming from it and I’ll check the valves and everything thank you.

 

[78 GMC Jimmy]

Try some AT-205 additive. If the valve guide seals are tired, it can rejuvenate them.