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MG Midget and Sprite Technical - Messed Up My Timing

Hi All

I have really messed up my ignition timing

its a 1275 Marina engine. When trying to start all I get is a backfire from the exhaust. I have rotated the engine to 7 BTDC with No 1 cylinder on compression stroke the rotor arm is pointing to No1 lead on the cap and the points are just beginning to open. Yesterday in frustration I pulled the dizzy drive from the engine to checkit was ok, I am certain this is back ok, replaced with the engine at TDC and the smaller part towards the front of the engine with it twisting to the 11o clock position.
I have checked all again this morning and cant for the life of me see what I am doing wrong.

Thanks Ian
I Pickering

Just to add the car was running last weekend I decided to ceck the static timing and it has not run since. If I aint broke dont fix it!!!!!
Thanks Ian
I Pickering

Just an update I have been comparing the midget and marina manuals and the position for the dizzy drive is different in both books I have set mine to the marina manual, but I cant understand why they should be different as they are basically the same engine as I understand.
Thanks Ian
I Pickering

Ian

When you say you decided to check the static timing, what did you actually do? If you moved the distributor and it then wouldn't start, why didn't you put it back to where it was?
Also, why did you pull the dissy drive?

Are you sure the engine is at TDC? When your timing marks are aligned, have you checked that no.1 piston is at the top of its stroke?
Dave O'Neill 2

Dave I did move the distributor and I also put it back but it still would not start I pulled the dizzy drive because it felt like there was excees play between the dizzy shaft and the drive but this is not the case. I have checked no.1 piston is at TDC with a dial gauge also both valves are closed and no.4 valves are just moving.

Thanks Ian
I Pickering

It sounds like you are doing everything right, but that can't be the case or it would be running.
We must be missing something.
Dave O'Neill 2

DONE IT !!!

Gave up with the books for reinserting the dizzy drive. I could remember where my dizzy was originally and I could remember where the rotor arm was for No.1. So I pulled the drive back out and offered it to the dizzy with the rotor arm in the correct position put it all back together and set the timing she fired up almost instantly had to shut off quick because I have removed the rad to make things a little easier for the timing marks. It must be one of those little A Series mysteries..

Thanks Ian
I Pickering

Just a thought

while you got the rad off.

make up a pointer to put on the engine plate and set the pully to TDC...and RE-mark the pulley (TDC) with your new pointer so you can now time the pulley from up on top...

then get one of those new timimng lights that can advance the timing light strobe....

if you want the timing at 10 degrees, you simply set it at the light, then aim at your NEW TDC mark on the pulley ...the timing light makes the adjustment.


Prop
Prop

something i found and will be installing soon....

http://advanceddistributors.mybisi.com/product/84779/1275-Midget-Sprite-Timing-Tape-Kit_404923.html
Chris Edwards

Prop
I was already thinking those thoughts. Here is the timing thingamajig I made this afternoon. This should make it easier in the future I hope...


I Pickering

Vary Nice I. Are the teeth calabrated or just copied from the teeth below

Chris...Ive got that...It is nice. Before I installed, I took the orginal to kinkos and copied several strips on sticky paper in the exact same size, that way I have back ups for when they get damaged...I also went to the post office and bought a roll of clear packing tape and put the tape over the top on the pulley to protect the timing tape.

But For $75 you can got to sears and get a new timing light with the advance knob like I was saying before so all you need is the TDC mark on the pulley

http://www.sears.com/shc/s/p_10153_12605_00914065000P?keyword=timing+light

Prop
Prop

This thread was discussed between 10/04/2010 and 11/04/2010

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