Just put in a rebuilt engine new rebuilt carb timing is right on but the thing wont start with the starter . Drag it on a tow strap and it starts and runs fine no vacuum leaks idles good. Any ideas?

 

Fresh rebuilds need to seat in to build up compression. They often don't have enough compression to start on thier own with the low rpms of the starter. Once you get it started, let it run, watching for leaks and the temps.

A little motor oil down the carb will help build compression for starts.

 

My fresh rebuild is doing the same thing. It started right up on the first start, idled great for about 45min. but after shutdown it will not start. It will get some oil squirted into the chambers tomorrow so I can finish the break in idle as it was getting late out.

Thanks, Ed