starter motor HELP

[timberman2004]

gentlemen (&Ladies)

Recently acquired a 1971 Moggy Traveller after many years lusting after one ..
He starts fine when warm / hot, and 'catches really easily, firing up properly ....
But when cold the starter motor REALLY struggles, barely turning the engine over...almost like the compression is too great for the starter...which im sure it cant be

The problem does NOT appear to be a poor battery and have had the dynamo tested for delivering the right charge ...so does it sound like the starter might be shot ? or is this perhaps a brushes issue ?

All / any help gratefully recieved

[bmcecosse]

It most likely IS a poor battery - perhaps draining overnight - perhaps bad connections. Does the engine appear to be kicking against the starter - indicating over advanced ignition timing.

[mike.perry]

Have you learnt to use the starting handle??

[The vast minority]

Technically yes it could be the starter but could also be the battery.
The cold engine needs loads more torque from the starter to turn it over, if it's in need of a repair it can show up as poor cold performance.

However, the same cold engine, given that it takes much more torque to turn over, draws many many more amps from the battery. Thus, a battery that holds good charge and seems fine on a warm engine can and most often is, the reason why a cold engine struggles to turn over.

The easy way to test is, use another battery, directly if poss rather than jump cables. Did it turn over much better? If so, problem found and it's the battery.
If it did not, you may be into starter removal territory so budget 20 minutes work for that.

Al

[ianmack]

If the battery is good a slow starter can often be caused by poor earthing between the engine and body. The Minor should have an earth braid from the gearbox to the floor with good connections at both ends. I once resolved this on a very rusty Land Rover by running an extra earth from the engine block direct to the battery earth terminal.

[biomed32uk]

I would second the poor earthing, I have just had similar following my winter rebuild.

No matter what I did I had a reading of about 30 ohms, from the battery negative terminal to anywhere else on the car body. After tracking it back it was the lug crimped to the battery negative cable where it attaches to the body. On the wiggle test it was coming and going and even managed to go open. A very manky rotten crimp.

A cheap multimeter is a very worthwhile addidtion to the car toolkit, nothing fancy needed for Minor use and is a great tool for electrical problems.

£5 off of the bay for a new battery negative cable and all sorted.