Thanks for taking a listen Steptoe. I do have a stethoscope, the sound is definitely coming from the top end. I can't seem to pinpoint it to a specific rocker arm though it seems more pronounced on the drivers side.
So u have put the stethosope on each of the lifters and studs....
Have u gone around the block, front sides etc
Have u also gone around from underneathe and listened from underneath as I asked?
The timing has no effect on the sound, however.
That is not where I was going with the question.
Have u put the stethoscope on the alternater, power stering pump, bellhousing etc etc?
When a tick, or "chirp" is being a real mother to locate, and only happens when warmed up, it is not uncommon it is a collasped piston skirt or cracked piston....which in some cases is heard a little to a lot clearer from under the car....and often with stethoscope on the side or front or rear of the block.
The issue with a colapsed piston skirt (or cracked piston) is it resonates around the engine and often damn near impossible to locate positively....about theonly think that cant be located possivily in most cases.
1/Pistons assumed to be the same diam by the machinist (and these days its very very rare pistons are not matche in a set..but If someone mixes a box...and happens) and the final hone of each pot is not matched to each piston.
2/A box of pistons has at some stage been accidently dropped
3/On intial fireup the advance has not been prset...engine turned over while the dizzy is turned (common practice) fires and advance is still way to advanced or retarded....this in the 1st couple seconds causes instant un even expansion rates between different alloys causes one of the piston skirts to grab , twist and colaspse.
4/ A lean condition on 1st fire resulting in the same as 3/
Generally it is a combination of 3 and 4 that causes this to happen.
The engine fires up nice, warms up and clicks/knocks/chirps taps
The engine has no drop off in performance
The "chirp" usually stops under medum to heavy loads
Is often more noticable under very light just off cruise condition.
usually heard clearer from under the car on a hoist.
Please when i say "usually" "often" take that literally....that is the nature of cracked and collasped pistons which is rather unque compared to other issues...espec when using a stethoscope, lifters, accessories and stuff.
I have had personal experiance in this and had the fortunate opportunty to have been in forensic labortories on this subject
I do certainly hope this is not the case and it is something far more simple.
The manfacture has fronted up here...and full cudos for doing so....they have publicaly offered to take things further....work with them and for now give them full benifit of doubt.