Morris Minor Owners Club

Sounds like the starter motor may have jammed.

Yes, I have had that before on my freshly rebuilt 1380, I panicked and did the same and it freed off. It was my starter that had jammed!

yes, i think so, the starter will just jam now and then ... anyone know why ? is it just when its worn ?

anyway it has a square nut on the back of it that you can turn with a spanner to free it.

cheers
grainger

Yes it is a fairly common problem that can be caused by different things, 1st a worn bendix on the end of the starter this is the part that engages with the flywheel to turn the engine over and can get quite worn, it is possible to replace just the bendix but re-con starters are not that expensive, 2nd a worn ring gear on the flywheel this can be seen through the starter hole, for some reason this only occurs in 1 or 2 positions, which means the engine always stops in 2 positions (anyone know why) worst job of the 3 to do as it means gearbox out and new ring gear on the flywheel, 3rd and easiest to cure and also probably most common is dirt on the bendix shaft, so often when removed and cleaned it is then oiled, when in fact this should be totally avoided as this will allow the shaft to pick up every bit of dirt thats around and cause the bendix to stick, when cleaning the shaft it must only be lubricated with plain graphite, the best source being a soft lead H2B pencil rubbed (quite heavily) along the shaft.
The starter is easy to remove so take it out and clean it I bet its got a dirty shaft.

Benny,

The only lubricant you should use on the starter pinions is graphite - not oil/grease. If it's oily, the pinion will pick up bits of dirt etc and these tend to cause the pinion to jam....

(Actually, rocking the car in top gear should be less effort)

The reason the starter ring has two worn spots is that the engine always comes to rest as one cylinder is "on compression" - that's when you have the maximum resistance to turning, and 'cos it's a 4 stroke, this happens 180 degrees apart.
There's an old dodge of turning the starter ring 90 degrees to salvage the situation - I'd reckon that by the time you've got it off it's just as economical to fit a new one..

Luck,

Colin

Colin, I would be amazed if you could get an old starter ring
off without splitting it with a cold chisel! Then you would have
to redo the 1/4 mark which is supposed to be fitted at the
number one cylinder top dead centre position. As you say
hardly worth the effort.

Willie,

I must admit I'm referring to my memory of Practical Motorist - not personal experience. I'm reasonable ok for mechanical/electrical/woodwork, but I know my limits with the tools and facilities I have!

I think I'd need outside help for this.

Colin

(Actually, rocking the car in top gear should be less effort)

Colin the car is easier to rock in 2nd as Benny did, the gearing for 4th makes it far more difficult to rock.

Kevin,

I haven't had to do this for a long time, but:
Top gear is 1:1 in the gearbox, so it's only the final ratio (4.22:1 for me) between roadwheel and engine.
2nd gear is reduced between engine and rear axle, so you're pushing 4.22:1 times the 2nd gear ratio.
That should mean that it's easier to turn the engine by using top gear when pushing the car (more torque - lower rpm) than 2nd. (i.e bump starting etc)

Do I need to go back to the meccano set (TM) and try it out again (after all those years!)

Colin

Colin your Ratios are fine for the effort put in ( in my case 13 1/2 stone ) but you have them reversed for the same effort in 4th the car would move 1 revolution but in 2nd it would move 4.22 revolutions, which means in theory that you only need a quarter of the effort for the same result, we are talking a stationary car with a jammed starter, not bump starting the car.

back to the tangent of the 'worn starter ring' - can you rotate the whole flywheel 90 degrees instead - it has just 4 bolts to the crank......??

Yes but is really worth the effort when you have it all apart, a new ring gear will last for a long long time.