put compressed air into the cylinder, sure nough it was coming out of tailpipe. ok . great. now what. wanted to know if i could pull the head and just change the intake and exhuast valves and put it back together. or just buy a used head, slap her on and ride. used will run $100 plus all the gaskets. valves, old head, plus gaskets upto $100 i'm thinking. this is a $400 beater 3.9l b250. rusty . just finished rebuilding the rear leaf spring mounts to make safe. but it has a crap load of new parts when i bought it.

 

Double check your timing & make sure both valves are closed in cyl 3. If you still get air thru exhaust then you have to do the work - no is no easy way out.

If you think the body/chassis rust progress will hold off long enough then you may wish to do the valve job right. Since the head has to come off you might as well do both heads and change the timing gears and timing chain as well. New valves shouldn't be too expensive or you can go to the junkyard and get a set from a low mileage engine (if you can find one).

It would really stink to have this happen on the other head after you fix #3. Plus, new valve guide seals will greatly reduce your oil consumption, which I will assume is probably about 1Q per 1,500 mi at this point in your engine's life.

 

That doesn't mean anything since the cam could be in the correct position to hold the exhaust valve open. You either need to make sure both valves are closed, or better yet, test the cylinder with a compression tester.

 

did the compression test. i have a previous thread about having 0 compression in cyl 3. took off rocker and had the same deal. air blowing thru exhaust. other than that starts up really fast better than my other cars and its only running on 5 cylinders.