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MG Midget and Sprite Technical - Dizzy drive shaft position

Can I just check that I'm not being totally stupid. Provided that No.1 cylinder is at TDC on the firing stroke, the dizzy drive shaft only needs to be in approx in the right position (main/larger offset to the top and a tooth one way or the other) so long as the dizzy can be moved to a position where the points are opening and firing up No.1 cylinder. Or does it have to be precise?
Chris H (1970 Midget 1275)

Chris, it can theoreticly be in any position, as long as the dizzy is in the correct position in relation to the drive.
Dave O'Neill 2

As Dave rightly says, however the reason why the drive is generally put in the same position by all engine builders is so that the dissy is always fitted the same, the plug leads are always the same and more importantly the vac unit does not foul anything when adjusting the timing.
Bob Turbo Midget England

I started thinking like you, but ended up thinking like Bob. I timed it nicely and all was lovely, but the vac hose was in a horrible position and likely to be torn off at a moment's notice. So I removed the dizzy, removed the dizzy-drive, put it back, missed, spent a long time fertling around trying to retrieve it, then banged my head against the wall at the stupid position I now found myself in. One slip of the fingers and having had the engine running and timed earlier that same day I now needed to crawl underneath and remove the sump pan. And buy a new gasket. And clean off all the old jointing compound which I'd beautifully assembled on the engine stand 2 days earlier. ARGHHHHH

I will never ever ever drop the dizzy drive into my sump ever again. Never. Ever.

Ant
Ant Allen

you will if you dont screw a rocker stud into the end of it while you guide it into position. Thats what they are for!! So easy with hindsight!
Bob Turbo Midget England

I had a bolt screwed into it. Only when I dropped it did I realise that I needed a longer bolt. When I finally installed it correctly I had a good foot from a length of threaded bar in it!
Ant Allen

Ant, don't worry - I did the same only on a Mini Cooper, had to strip down the clutch, drop gears, and remove the gearbox to retrieve the b thing. Luckily the unit was still on the workshop floor being assembled but it still took all evening and well into the night to get back to where I started. That was all of 30 years ago - you don't forget !
David Smith

Hmmm
A mate of mine did that in a Metro some years ago David and rang me crying on the phone. I thought the problem was easier than the midget, we simply removed the end cover from the gearbox (opposite end to the drop gears and clutch) and Bobs your uncle.
Robert (Bob) Midget Turbo

This thread was discussed on 10/03/2010

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