Had one of those happy accidents which happens now and again in the restoration of old aircraft/cars /motorcyles.
I had bought an airchute (duct really) for the Gipsy major which arrived yesterday. This bolts onto the left side of the cylinders and directs the air coming into the intake on the nose cowling onto the cooling fins of the engine cylinders.
I bought a three piece duct which looked correct after consulting the engine manual. However what I should have been consulting was the Parts manual as you will see.
When I got the new part home I tried to figure out how it went together. Two parts forming the longitudinal part of the duct were there, but I couldn't figure out why the part i had (called the rear) didn't seem to line up.
I went and consulted my Gipsy major manual and had a forehead smacking moment.
The rear part of the chute is called the rear baffle and i hadn't got that at all.
There were clearly TWO styles of airchute, one for the early Gipsy major and one for the later marks.
I had got the later mark chute and what i thought was the "rear" or rear baffle was actually the rear HALF of an early chute!! Bugger.
So Saturday saw me nip out to have a chat with my friend Anthony(who is rebuilding a Auster T7) and show him the bits I had and have a look at his parts manual, then look through all his airchute parts he had to try and find an end plate for mine.
As we sipped coffee and studied the manual we both realised something.
My Auster has the Gipsy Major 1 series engine so would use the early airchute.
Anthony has the later Gipsy Major 10-2 (used on the MK 6 and 7 Austers and also Chipmunks).
I had bought the later airchute.
He had the early model airchute.
You guessed it, we swapped! I now have the correct airchute for my engine and Anthony has the correct one for his! (Although he will need to find the rear baffle).
Just so you can see what I've been going on about here are the parts book exploded views:
This is the early style. Not shown clearly is the fact that the item marked "Scoop" is actually two parts and I had bought a rear half and not the item marked "rear baffle"

And the later one. I had bought items 2 and 6.

And this is the early rear half of the airchute "scoop". This is NOS (New Old Stock) and I now have a couple of them with the bits Anthony has traded with me. ;D

So a good day in the Auster world!