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MG Midget and Sprite Technical - midget 1500 timing marks

hya all

iv got myself a strobe of a friend and want to check the ignition timing, theres 2 paint marks one on the pulley slot and theres some like spike type things located on top of the pully on the engine block witch has the same paint mark on. i havnt a clue where the marks are or where to set it too, what rpm ect. il try and get a pic up to show
james gibson

On a 1500 the marks are as follows:

Notch in pulley indicates TDC

Large pointer on timing cover indicates TDC.

Small pointers on timing cover either side of TDC pointer are each 2 degrees before and after TDC.

The book says to time in 10 degrees BEFORE TDC (note: engine rotates clockwise when viewed from the front) at 680 rpm - I prefer to do it at 1000 rpm because this gives better, more consistent, results.
Deborah Evans

sorry can't resist - this sort of info is in the owmers Handbook, quicker and easier to flick to a paper page in it than to use the computer/phone/whatever electronic box

it's always a good place to start from on things like this but I do concede that the passing of time and experience can sometimes move things on

there are quite a few elements to getting the engine running at its best which are covered in thev treasured book - not that the engine is a priority on a car
N Atkins

the only other problem is the carbs not set up correctly eather. does it not matter how the carbs setup as long as its revving at the rite rpm and then set the mixture up afterwards. i dont have the book and i want to no the settings now not wait 3-4 days for it to be delivered, as where i can get a responce on here within miniutes

cheers anyway
james gibson

Wind the jets up until they are level with the bridge (you need to take the dashpots off to see this). Now wind them down 2 full turns (12 flats). This will put you in a safe ballpark to start the car and set up the timing. Ensure the carb piston damper tubes are filled with 20/50 oil

Start engine and bring to temp. Then set the dynamic timing - 10 degrees BTDC @ 1000 rpm.

Then get on an exhaust gas analyser and set the mixture.

You'll probably find that around 8 - 10 flats is the correct mixture.
Deborah Evans

sorry James I didn't mean to be , well mean, I wasn't holding back on the answer I just didn't know it (I only have a 1275 Handbook) so left it to others

you can ask as many questions as you like or need with or without the book

once you've got the book you'll be able to answer some of the questions put by others !

when you see the full service schedule you'll see you may have to alter whatever settings you have now

I always suggest a full 36,000 mile service plus other bits on a car you've not owned for long as it's sets the car up to run well and reduces the potential for problems and breakdowns

I've read that as part of a full annual service it's set up tappets, points, timing and mixture in that order but don't worry about that until you get to that stage in your servicing of the car

as you know I also recommend the paper Part Catalogue and Heritage DVD

another area of variance in the Handbook although still fine as a starting point or without other information is to increase the psi by about 2 for modern tyres and if the tyres are 6 years or older regardless of thread left change them ASAP you will notice the important improvement
N Atkins

Deborah Evans , took your advice and done exactly what you siad runs better than it ever has done and pulls like a train now!!!

many thanx
james gibson

This thread was discussed on 04/07/2011

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