Morris Minor Owners Club

Hi all, I have a Morris Minor MM (lowlight - sidevalve) and I would like to know how much the degrees of the distributor should be.
Any help appreciated.

Thanx.

Start with it set at TDC - and then advance it very slightly bit by bit until you hear some 'pinking' when the engine is working hard - then retard it slightly. You now have the optimum setting for your engine.

Can you help me a little bit here pls? What's a TDC?

Top dead centre

when piston number one (the one nearest the radiator) is at the top of its compression stroke

hey, I'm a bit of a dur on this and have to do the same at the weekend as I'm taking the engine out...

Do you mean when piston number 1 is at TDC, then the distributor should be 0 degrees?

KirstMin, the above info is for the Series MM Minor (sidevalve) and not the later A-series cars.

thanks

Same idea applies to all ! No 1 piston at Top Dead Centre with both valves closed. You need to arrange for the spark from the dizzy to happen at this precise point. When the engine is actually running - various factors mean that the spark is better arranged to happen slightly BEFORE TDC - and so the ignition is advanced. If it's too far advanced there will be 'pinking' when the engine is under load (bad for the pistons !) and possibly the engine will 'kick' against the starter motor when cranking from cold (bad for the starter !) so both of these are to be avoided. Best plan then is to advance the timing until pinking appears - then retard it slightly - with the caveat that if it then shows signs of kicking on the starter it must be retarded slightly more. Easiest way to find the spark is to connect # 1 lead to a spare spark plug lying on the engine - and slowly turn the engine over with the starting handle till it sparks !

bmcecosse wrote:Same idea applies to all !

**sigh** yes, I was waiting for you to comment on that. Of course they all operate on the Otto cycle principle, but:

The later cars have a starting point for the timing (around 5 degrees), whereas the MM is 0 degrees.

I just did not want Kirstmin adjusting the 1098's timing to 0 degrees and then wondering why the car runs very badly!

The 'starting' point doesn't matter a hoot - these are just pre-set average figures from the factory - set it my way to get the correct setting for your engine.

So why bother wasting space in the manual and specifying them from the factory then if it doesn't matter a hoot?

I simply did not want to confuse Kirstmin by setting the A-series to zero degrees and then running the car and wondering why it doesn't go very well as the A-series doesn't much like TDC.

In any case, setting it at 5 degrees is much healthier for the engine than running it on the edge of pinking as varing fuel/heat/load can then set pinking off and the advantage gained through setting it 'on the edge' will be very minimal. Just as a note though, the 1275s like around 8 degrees.

I think I get it! Thanks both... as long as I get the thing to the rolling road I'll be happy

Well, thanx guys for the help you have provided me... The problem I have right now and that's why I want to know about the distributor is that the Moggies won't go over 35 miles. It goes 35 miles with the third gear and when I put the forth gear it doesn't accelerate. It goes 35 or less so I have to put the theird gear again. By fixing the distributor degrees will it solve the problem?

Thanx again.

I think it might, and check you carb/points etc.


(and your speedo)

The sidevalve engine has that type of feel though. You need to get the revs up before changing to top gear (4th) as otherwise you'll need to change back down again as it hasn't got a lot of power. Mind you, it should cruise quite happily at 50 MPH. It will go faster, but the sidevalves seem to like 50! If yours can't get to 50 MPH then check the timing and carb mixture setting.

Thank you all for the help. I will look into it.

Cheers.