Hi Steve, welcome to Outdoorking.
Please post the Model, Type and Code numbers for that Briggs engine. They are always on there somewhere, usually on the top cowl. At present if I take a guess, it would be that you have an Intek engine, and you need to adjust the exhaust valve tappet clearance. On the large Inteks you have to set the clearance to 0.006" - if with minor wear it gets to 0.009", the decompressor stops working and you get exactly the results you have described. It is a very common problem. Briggs specify that you must adjust the tappets every year, and they mean it: if you don't, you end up with it not cranking, and making unnecessary replacements of costly electrical parts.
If it isn't an Intek, we will have to go through a diagnostic procedure, when we know exactly what the engine is.
