KOEL built the AV1 series II under licenes, in fact they still build it and still call it the AV1.
The air cooled is a different matter, they don't call it an AVA1 and this one seems to have an SAE bell housing ( or Brittish era equiv ).
Maybe Peter can clear this up, did Petter make an PH1 with bell housing around the fly wheel like later engines such as the ASJW and PHJW but in an air cooled?
More confusing the AV1 has a 80mm bore does, the TA1 has a 87.5 mm bore. Both share the same crank...
So I guess this is technicaly closer the the PH1
Doug
After Hawker-Siddeley took over Petters, and before the merger with R A Lister, there was a big push by Hawker-Siddeley to get industrialised engine output up from what Petters were doing.
SAE bellhousings WERE available for most engines, and those that had them went to generator builders.
The SAE standards were adopted over here way back when.
The KOEL AV1 shows a different, Deutz-like air cooling arrangement, which may or may not be better, but it certainly uses more resources to put together and uses wearing parts like belts and bearings. None of the UK engines had anything like that.
Peter