Hello All Let me preface this post by saying I am no mechanic. I tinker, but I am by no means going to be able to adjust rocker lash. I have watched about 5 videos on how to do it, but honestly would not feel comfortable ripping valve covers off and jumping in. I am gonna have to pay someone. Also, I am not in a place where I know anyone in my present neighborhood and unfortunately can't persuade a mechanically inclined neighbor with a very old bottle of scotch to help teach me. I have an '89 350 that has about 114K on the clock since last rebuild (214k aggregate on the motor). It has just started running rough and sometimes hesitating, but seems to only do it after it has warmed up. To add to that, when driving I catch a faint whiff of ozone (burning plastic smell). I changed the fuel filter, added gas additive to combat any water in the fuel, cleaned the throttlebody with TB cleaner, and cleaned and re-oiled the K&N air filters. I have plans to replace the motor (thinking a Jasper, local company installs them in 3 days, +warranty, all under 3k OTD) sometime when I can scrape together $2750. Meantime, what can I do to make it happier? What could be the issue? In trying to think this through I have researched a lot on the interwebz. I am thinking possibly four things. I realize that there could be a couple of these things going on as well, and a red herring could be taking me on a different tack than if I had just had one of them. I think it could be either a newly loose motor mount (but would not explain the sometimes hesitation), or top end (timing chain, and or valves needing adjusted), or a vacumn leak (do these sometimes just 'happen' after a while?), or an exhaust leak (prolly headers/gasket if that is the case, from the y back--cat, pipe, muff--all is new 3"). Should I be looking at anything else? Here is where I need you folks' opinions. Do I have the 'workaround' jobs done or just get the replacement motor? Should I instead have someone pull my motor out, gut the thing, and rebuild it? If I do it piecemeal, will doing the top end job add stress on the bottom end (when talking with buddies while 'helping' them on their motorcycle engine rebuilds, I was always told to do the whole thing at the same time)? Apologies on all the questions, I am a relatively new 350 owner, I've only had the Shebby for about 2 years (and I want to keep the rig...it is paid for) If this is not enough info, lemme know what I can do to clarify. Thanks in advance, Jay Wanna kill these ads? We can help!