RE: Welcome to Club SAITO !
This is a great thread. I have gathered a lot of valuable knowledge of Saito engines here. Perhaps the great Saito gurus can clear up some things for me.
My FA-72 (ca. 2002, rev G, no choke) chewed and partially blew the intake manifold-head o-ring causing an in flight flame out. From what I have read here, this was an inevitable eventuality for a 72 and I will try the published remedies. It may have been the result of a lean run overheating the seal when the pressure tap gnawed itself out of an older style machined muffler on a prior flight (hard to believe they designed the tap to thread with half the diameter in, the other half out, of the too short baffle/end cap threads).
I ordered a carb gasket set (8091B) to replace the manifold seals, and an engine gasket set (7232A) to have on hand.
In the carb kit, I find the 2 intake o-rings (one labeled "Viton" assumed to be the head end?) and metal compression washer. I also find some additional items that I do not see in the manual's exploded view (the pictures in both old and new manuals appear to be down-level, incomplete, or of a different engine model):
1 o-ring ~11mm x 8mm x 1.5mm (same as the carb-intake manifold seal)
1 o-ring ~5mm x 2mm x 1.5mm
1 o-ring ~5mm x 4mm x 0.5mm
1 o-ring ~3mm x 2mm x 0.5mm (in the Viton bag)
1 white plastic washer about the size of the intake seals.
In the engine kit, I recognize the cam and rocker cover gaskets as well as another set of intake manifold seals (but no metal washer). The backplate gasket shown in the manual is not included. Is it not used on models with plastic backplates? There is also yet another unidentified seal:
1 o-ring ~4mm x 3mm x 0.5mm
So, my questions are:
What are these extra parts I have listed for?
Why no backplate gasket as shown in the documentation?
Are there more up to date/more complete exploded views or documentation available somewhere?