bad valve seat
 

there is oil coming out of my number one exhaust manifold i am thinking it is a bad valve seat. the truck has 178000 miles on it which is low for a 96 the truck was stock when i got it at 170000 miles. and it ran good it had some oil leaks and a bad clutch i got it for $4800. but when i got it home i notice that it had a loud noise sound like the fan was hitting the shroud. since the clutch was bad we fix the kdp, new front rear main, new valve cover gaskets and some other stuff since it was down. so we had the valve cover off we adjust the valve and took notice that the number one exhaust valve was way off and the other valves were a little off so we adjusted them to spec. start the truck up and the loud noise was gone and the engine runs really smooth know but that was a little over a year now. truck still runs smooth and had know trouble with it at all. the other week i open the hood to check the oil and there is oil on my hood where it has sprayed out. I started run amsoil in every thing about 3,000 miles ago and notice it started leaking tranny oil and the diff. started wiping oil and it made the front axle seals leak to. could the amsoil make the valve seals leak to.

Amsoil has a lot of detergents in it. these detergents actually wash away what could have been gunked up inside the seals and made them start leaking. a very common problem in vehicles where standard oil is swapped for synthetic oils. not to mention these seals were probably factory and designed to control factory oils!

should i go back to the old oil or the cummins blue oil or is it to late

you can go back and the leaks may stop or slow down but if you have replaced any seals then i would just stick with the synthetic. i started running amsoil in mine and every seal on the engine started leaking including the oil pan gasket. but since the engine has been completely resealed no leaks so far and it is easier to start cold and maintains oil pressure much better not to mention the amsoil holds the diesel soot and actually drains the engine cleaner during oil changes. in other words the new oil isnt immediately black after a change.

valve seal or valve cover? a bad valve seat wont make it leak oil, a vlave guide would though... just a little confused with whats leaking

how loud where the valves, when they were un adjusted? my truck sounds terrible like arod knock but it goes away if you give it some peddle , around 1500 rpm it sounds fine

agree``