good advice..
Valve stem seals CAN cause oil burning on start up, but its the VALVE GUIDES themselves that are loose enough to pass excessive oil into the cylinders..the seals are just that,seals!--they can only do so much,if the giudes or valve stems are worn enough,it'll smoke regardless of how good the seals are--you have 20 inches of vacuum pulling the oil past them at idle!..if they are loose enough,idle will suffer too--its a vacuum leak!..
You have to realize everything in an engine wears,at the same rate..replacing only the heads, with a fresh "valve job" often results in an engine that smokes MUCH more than it ever did before,because the oil is now forced past the points of least resistance that are still worn--like the rings and pistons,and scores in the cylinders..
You'll find you wasted time and money,and hours of back breaking labor,that would have been easier to do had you pulled the motor right out!...it took me about 5 times to decide "valve jobs" are not worth the effort,if thats all your going to do..replacing heads with the motor in the truck sucks...
Three times out of five in my trucks ,the motor had to be replaced with another,because it smoked so badly you couldn't drive it on public streets without being pulled over and ticketed for excessive smoking,after the "rebuilt" heads were insrtalled!..
...and to add insult to injury,the 350 motors I bought from junkyards ran sweet,and at 300 bucks,they were 150 bucks cheaper than having the heads done over,and now I had an expensive "half rebuilt" small block gathering dust in my shop!..
Not to say you can't slap a set of valve stem seals on it,and get favorable results!..but don't be too dissapointed if it turns out worse !..its best to do everything at once,and get it over with..
Valve stem seals CAN cause oil burning on start up, but its the VALVE GUIDES themselves that are loose enough to pass excessive oil into the cylinders..the seals are just that,seals!--they can only do so much,if the giudes or valve stems are worn enough,it'll smoke regardless of how good the seals are--you have 20 inches of vacuum pulling the oil past them at idle!..if they are loose enough,idle will suffer too--its a vacuum leak!..
You have to realize everything in an engine wears,at the same rate..replacing only the heads, with a fresh "valve job" often results in an engine that smokes MUCH more than it ever did before,because the oil is now forced past the points of least resistance that are still worn--like the rings and pistons,and scores in the cylinders..
You'll find you wasted time and money,and hours of back breaking labor,that would have been easier to do had you pulled the motor right out!...it took me about 5 times to decide "valve jobs" are not worth the effort,if thats all your going to do..replacing heads with the motor in the truck sucks...
Three times out of five in my trucks ,the motor had to be replaced with another,because it smoked so badly you couldn't drive it on public streets without being pulled over and ticketed for excessive smoking,after the "rebuilt" heads were insrtalled!..
...and to add insult to injury,the 350 motors I bought from junkyards ran sweet,and at 300 bucks,they were 150 bucks cheaper than having the heads done over,and now I had an expensive "half rebuilt" small block gathering dust in my shop!.. Not to say you can't slap a set of valve stem seals on it,and get favorable results!..but don't be too dissapointed if it turns out worse !..its best to do everything at once,and get it over with..
---Time to rebuild/replace engine.
