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MG MGA - Dizzy me

Hey all,

The body is not yet on the car and I want to "set-up" the carbs and dizzy to enable it to start, (if I ever get that far)!

I backed the carbs down 2 turns but I don't know where to set the dizzy/roter. The motor is at TDC. Any one done this with sucess?

As you must all be aware, adjusting with the body off is easy.

Thanks again, Tom
Thomas McNamara

Thomas,

The workshop manual isn't all that clear on the proceedure. Go to the guru of MGA's, try this link to Barney's very detailed explination. It has saved me many an hour. http://mgaguru.com/mgtech/ignition/ig103.htm

John
jbackman

OK, I', learning a lot. Next question; how long are the bolts that hold the dizzy mounting plate to the block?

After reading Barney's info, the rotor points at # 1 spark plug and the dizzy re-builder says 10-14 degrees BTDC. How the heck can this be presset? Tom
Thomas McNamara

Thomas. You may wish to go to the MG section on my website, www.custompistols.com/ and read the tech article on ignition timing. It explains both static timing and dynamic timing. You would static time your dizzy for initial start up if doing it yourself.

Les
Les Bengtson

Static setting of ignition timing: Turn engine to position #1 piston at TDC on compression stroke (both valves closed). Position timing mark on the crank pulley at desired static setting. If the distributor is properly installed, the rotor will be pointing roughly in the direction of #1 spark plug. The rotor turns anti-clockwise when running. Loosen clamp bolt at base of distributor. Rotate distributor anti-clockwise until points are closed. Rotate slowly clockwise until points just start to open. Tighten clamp blot, and you're done.
Barney Gaylord

I'm probably picking a fight where none is warranted, but every time I see "dizzy" it strikes me the same as "veggies" or "Eggs Bennie". Just sorta annoying.

OK, I've said too much already. No offense.
David Breneman

David,I must admit I have called a distributor a "dizzy" a few times on this forum, I suppose that its just to save time inputting the whole word over and over again.

Its the same with carburettors, I usually call them carbs for the same reason (and it also avoids the other problem of getting the spelling correct!)

For some reason, the word "carbs" sounds ok whereas "dizzy" has a kind of out-of-balance feel to it :-)

You will have to come up with a suitable shorter word for distributor that everybody likes, maybe "distor", "disty" or "dstrb" although the last one looks more like "disturb"!

At least "dizzy" gives a impression something that is spinning!

Colyn

PS Couldnt help but notice that you used the word "sorta" instead of "sort of" David.
You have to be careful when you shorten these words in case someone out there gets slightly irritated! :-))
(Sorry)
Colyn Firth

Me too Colyn - dizzy is a commonly used abbreviation in these parts. Yes - "sorta" is sort of annoying !!
Cam Cunningham

Colyn, as you folks say, it's a fair cop. :-)
David Breneman

First scan attached. Static timing is 7 Degrees before top dead center, between the 5 and 10 pointers on the timing cover.
Russ

Russ Carnes

Picture 2. Sorry about the quality, the manual has been used quite a lot, not to mention cruising around in the boot for abour 50 years.
Russ

Russ Carnes

Full copy of the MGA Workshop Manual is here: http://mgaguru.com/mgtech/books/wsm.htm
Anyone who owns an MGA should have the book.
Barney Gaylord

On modern unleaded fuels you need to retard the ignition from WSM settings so 10 BTDC is a better starting point
dominic clancy

Dominic, would that not be more advanced?
N McGurk

This thread was discussed between 27/02/2012 and 03/03/2012

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