Starter motor can anyone help

[apgodden 7]

I have had problems with my 2b ever since I bought it roughly 6 weeks.  I thought the engine had a lot of compression and the starter was finding it hard to turn over.

Today I replaced the starter motor and no change. I replaced the battery and no change.

locked at the connections all look ok.  Cleaned all earth terminals. No change.

voltage is 12.8 volts and turning over is 11.3 volts.

turning over is very slow / hardly turning??????

[tractor 1,062]

i would come and help you but you are a long way away 

what are the cranking amps and ah on your battery 

[apgodden 7]

1 minute ago, tractor said:

i would come and help you but you are a long way away 

what are the cranking amps and ah on your battery 

Cranking amps not sure. It’s a 0.9kw starter motor and a 60 ah battery 

[richyb66 1,210]

Do the main power lead to the starter and the engine earth lead look up to the job i.e. like something you'd see on a production car? Does the power lead get hot when cranking?

[apgodden 7]

Hi Richy, yes the power leads look good and good size probably 25mm cable.  Cables do not get hot on cranking.

[tractor 1,062]

i have 70ah and cca620 on mine i know its a bit on the large side but i have plenty of power to turn engine over 

[richyb66 1,210]

Do you have any reason to suspect that the compression ratio has been raised? Can you double up the power lead to starter so you can be certain it's capable of passing enough current?

[apgodden 7]

No reason to think the compression has changed.  It was just it would always start but very slow cranking.

thought to change the starter motor.

i can double up the starter cable if you think that’s worth a try

[fry61 1,260]

If you are suspecting a tight engine is it worth trying cranking with one ( or more ) plugs removed?

[IanS 64]

If doubling the cable dont forget to double the earth back from the starter to the battery. A pair of jump leads?

Talking of jump leads have you tried connecting a second battery in parallel?

Slow cranking can also be a sign of over advanced ignition.

[fry61 1,260]

It was a brand new starter motor??

[apgodden 7]

10 hours ago, IanS said:

If doubling the cable dont forget to double the earth back from the starter to the battery. A pair of jump leads?

Talking of jump leads have you tried connecting a second battery in parallel?

Slow cranking can also be a sign of over advanced ignition.

I have put jumper cables from my wife's car with it running and its the same.

[apgodden 7]

9 hours ago, fry61 said:

It was a brand new starter motor??

Yes brand new starter and 60ah battery

[RedTrev 38]

11 hours ago, IanS said:

Slow cranking can also be a sign of over advanced ignition.

It's worth considering the point that Ian is making here. I experienced this with a 1380 tuned Mini (many) years ago. Try retarding the ignition timing or, alternatively, crank with the ignition electrically disconnected. If the engine turns freely with no ignition, you'll know it's ignition timing causing the issue.

[theduck 865]

Have you got any jump leads? Use these to add extra grounds between engine and chassis and / or gear box and chassis.  Quick way to tell if you need to improve the grounding.