400 four wont start

[Marcusash]

Hi.
I am struggling to get my 400 four started.
I have done a rebuild, so new harness, plugs, coils, points and caps.
Carbs stripped, cleaned and new jets, float needles etc.
New battery - fully charged.
I have freed the auto advance, the tappets are done and the static timing is spot on!
So this is what happens.
I do get a spark from all 4 plugs, and fuel is getting through.
When I press the starter for a few turns there is no spark at all, then it sparks, but seems very weak.
When I let go of the starter button the engine spins a few more turns and I continue to get a spark.
It seems as though the starter is taking too much juice initially, preventing the coils from firing up. Is this normal?
Any help, ideas would be very welcome.
Thanks.

[Cappodimonte]

Have a look at all your earthing points and clan them up, as soon as you let go of the stater button the starter motor should stop straightaway, might be the starter solenoid underneath the near side side panel may be faulty. Weak spark usually leads to faulty earth.

[K2-K6]

If the battery is new it shouldn't have difficulty in supplying enough to get you going.

As above post, is it turning the motor after you've let go of the button ?  Or is that partly running after the starter motor stops ?

[Johnny4428]

Sounds like a sticking starter solenoid. Possibly other things as well but sort one thing at a time. Possibly faulty at starter button. I had one starter button stuck on and drained battery.

[Marcusash]

Hi. Thanks for the replies.
I did consider a bad earth, so connected the battery earth direct to the green wire earthing the rectifier, no change.
Starter button is not sticking it is just the the afterspin.
Will check out the solenoid.
Thanks.

[K2-K6]

It's possible that you've got the points connected to the wrong coil (or in some configuration to do that) the system will spark like this as all the switching elements are working, but with 1+4 & 2+3 cylinders sparking at the bottom of the stroke rather than top.

It's easy to do this inadvertently, also easy to try swapping over by switching the points to coils plugs on the loom over to give opposed arrangement. Safe to try just swapping these two to try starting it.

Reality check (others have fallen into this trap before) one coil supplies the outer two cylinder 1+4 with the other coil for inner two 2+3, checking to make sure you're all good there too.

[McCabe-Thiele (Ted)]

Your coil wiring should be as follows.

The wire colour to the left hand CB points is   Blue  -  coil for 1 & 4 is the Blue wire at the coil end.

 The wire colour to the right hand CB points it's Yellow - coil for 2 & 3 is the Yellow wire at the coil end.

[Oddjob]

Does it start using the kickstart, if it does then it's most likely a starter motor problem or solenoid.

[McCabe-Thiele (Ted)]

Make sure you have fitted the points connections, insulators & capacitors correctly?

[ka-ja]

If you have stripped the advance/retard unit, have you got the cam on wrong? ie 180 degrees out.