I began doing some of the work on my Mini last night. I decided that I wasn’t going to remove my current engine until I have marked up and made the bulkhead modifications and box for the Weber, so last night I removed some of the ancillaries as well as my SU carburettor and its inlet manifold. I also went round to a mates house yesterday (the same guy who I’m hoping to buy my new engine from) to find that he has a lot of spares which I may be able to use.
The photo above shows my engine bay as it is now with my SU and inlet manifold removed. This took only about 10 minutes to get to this stage.
My mate – the guy with these various spares and what-not, had spares such as a straight cut gearbox, several sets of straight cut drop gears, a lightened flywheel and clutch assembly and various other interesting bits.
I was really hoping to especially buy the straight cut drop gears, because its something I really must have (for the sound!) and I know it’ll be cheaper than buying them brand new. The only thing was that we wasn’t sure what engine drop gears were for, and how to identify them. I asked the question on the Mini club forum, as well as the (usually more knowledged/more users) forum, The Mini Forum and I got a reply within a few hours.
GuessWorks said that the Input and Primary gear are the same weather A+ or A series, however the 998 Primary gear has a bush I/D of 1.5", whereas the 1275 Primary gear has an I/D of 1.625".
The idler gear is the difference; The A+ idler has even length shafts with an O/D of .875", and the A series has odd length shafts with an O/D of .75".
Finally, you can use an A series idler in an A+ gearbox / transfer case if you use the DAM3745 conversion bearing (Minispares part number), but an A+ idler cannot be used in an A series case.
That’s re-written slightly, but just to re-cap there are 3 gears in total and 4 different combinations of engine, 998 A, 998 A+, 1275 A, 1275 A+. From the above statement, it should be possible to work out one set of drop gears from another.
Not entirely sure what is meant by O/D and I/D, but I think it maybe something like Inner Diameter and Outer Diameter. I’ll keep this post updated with anything else I find with this, and how the whole thing goes.
[...] Following on from my post about identifying Mini drop gears – in particular straight cut drop gears – I came across an interesting article on MiniMania.com. I hope they don’t mind me pinching this information, but I want to just incase they take this article down in the future. [...]