Thanks Slowlane and Sgkent we will go through all those checks before messing with the AFM, we have all new vacuum tubes but will check again I'm still waiting on new AAR elbow, will recheck all grounds, I have an electronic ignition Crane Cams XR-700 with Fireball Coil PS20 and will check that too, as well as the fuel pressure and the fuel pump,SlowLane wrote: ↑Tue Jul 04, 2017 9:07 amSo what Steve (and I) are obliquely trying to get across is this: before you start mucking about with the AFM, make sure the fundamentals are in order.
To wit:
- Make sure that there are no vacuum leaks. The list of potential leak sources is extensive and has been covered in past topics. The smoke test that Steve recommends is a great way to "smoke them out"
- Make sure that all electrical connections are sound. Grounds as well.
- Make sure that your ignition is performing correctly. Not just a nice strong spark, but that the distributor is advancing smoothly as RPM increases and un-advancing just as smoothly as RPM decreases.
Too often a person will dive into the AFM trying to compensate for an undiagnosed vacuum leak because tweaking the AFM is more "wizardly" than chasing down mundane cracks in the rubber bits. Really, the factory setting of an AFM should be correct for pretty much the normal life of an engine.
- Make sure that your fuel pump is providing sufficient pressure and volume for all operating conditions.
It doesn't do it when engine is cold is when it gets up to operating temp, cross my fingers we will find whats wrong I will report back
thanks again