1996 Ford 460 Exhaust Manifold Problem! Solution?
Ok, on our 1996 Ford 460 motor home, we hear the clicking that indicates that there is an exhaust leak. A light clicking that we hear at engine start-up. I inspect for the notorious broken passenger side rear exhaust manifold bolt, and there it is, the stump of the broken off bolt head. Now this bolt is larger than the other manifold mounting fasteners. In fact it is a 3/8” bolt, is quite thick, not a nut on a 5/16” threaded rod.
So what are my options?
Option A: Try to “easy out” it out and replace the bolt? Can it be done? Am I wasting my time? Should I squirt in a penetrating solution to soften the grip on the threads? Or will that damaged the manifold gasket? Should I heat up the engine first and try to cool the broken bolt stud with a spray; right before trying to “easy out” it out? If I do this and I put a new bolt in, will the new bolt last? Should I use a high grade new bolt to keep it from happening again, or will that cause the manifold to crack to relieve this “design flaw” stress? Basically, should I try to get the broker off bolt out, and replace it, without taking the manifold off?
Option B; The part number for my right side manifold is ENGINEERING # RF-F5TE-9430-FA or better known as PART # F5TZ-9430-F. I just learned that the number stamped on the manifold is not the part number, but an engineering number. Anyway, checking with RockAuto.com, and a variety of other online auto part stores, reveals that my suggested part number is F6TZ-9430-NA. Hmm, this is different, very different. The gal at the Ford Truck parts counter confirms that my installed part # F5TZ-9430-F, is the correct part, and she has no idea of any WELL KNOWN 460 manifold problem, or why other retail outlets suggest a different part number. Anyway, I can have it changed out for about $350 in labor which includes a machining of the existing manifold. But, if the manifold is a design flaw, this is not good. So, should I try a newer designed part, a part that the Ford Parts gal’s computer is not aware of, perhaps part number F6TZ-9430-NA. So, what are the options to fix this problem with a new exhaust manifold, a different exhaust manifold???
Thanks for all your input.