AW11 starter

[jayray]

bump... any ideas?

I have tried a different starter relay, bashing the starter gently, turning the motor over so I know its not seized. Gearbox earth is good.

[chris77]

I lent my 89 mr2 to a guy at work , only had it a few weeks . After a couple of days he said the battery went flat and it would not start . I just got another battery but when I went to change it I found the battery was not tied down properly and the positive could short against the intercooler frame . I think it was slowly leaking to earth .

Unlikely to happen to someone esle but maybe something to check .

Chris

[whynot]

I had something like this on an old 4age and it turned out the bronze bushes were worn out and the starter was putting all its effort into over coming the wear and tear. it was really cheap to fix once I found the bushes and cleaned it up.

[NZ_AE86]

I would guess the starter is 'polling' from what you have said, it is due to the front bush being worn out often due to clutch dust contamination.

[jayray]

The battery clamp definitely isn't shorting the batteries out, I imagine that would be a one off event that you wouldn't forget quickly

Just need to test to see what voltage I'm getting at the solenoid, and if that circuit is healthy I'll remove the starter and have a better look at it this time.

Could the front bush wearing out be something that could cause the intermittent problem though?

Its something I will definitely check though, thanks

[jayray]

I've just been out and checked the voltage at the solenoid wire for the starter. Getting 11.6 V with battery at 12.4 V. Should this be enough?

The solenoid is definitely plunging in, and there's a decent clunk when it engages with the flywheel so I'd assume its the starter itself rather than the starter wiring?

[Guss]

mine did this, was fine when cold but even after a short drive it would not be able to start, i'd get a crank or two and if it didn't fire i was screwed for 1/2hr or so.
heat was definately the killer.

If you've held the key on start with starter engaged for a while while the rotor is stationary you could well have burnt the windings. Was there any funny burnt smell when you had the starter apart?

I got a 20V 2nd hand motor and swapped the motor body& armature onto the 16V gear reduction half, was pretty simple really - if i hadn't pulled the armature

[allencr]

I'll remove the starter and have a better look at it this time.

If the contacts on the end of the plunger were cleaned up, capable of feeding plenty of current to the motor, and the brushes are long enough & slide freely in their holders & commutator on the armature that they contact is smooth & clean, then there isn't much else you can do. The bearings can have LOTS of play, 2-3mm, and it should still work like new.

[matt dunn]

If the contacts on the end of the plunger were cleaned up, capable of feeding plenty of current to the motor, and the brushes are long enough & slide freely in their holders & commutator on the armature that they contact is smooth & clean, then there isn't much else you can do. The bearings can have LOTS of play, 2-3mm, and it should still work like new.

No, no and no.

The solenoids are sealed, you cant get into them,
the dont have any bearings in them at al,
and a small amount of wear in the front bush which happens,
causes the whole armature to run on the poles in the middle,
and really slows them down, and can get to where they wont tun the engine over.

[matt dunn]

Also if your still getting 12.4v at the battery with the key turned,
then i'd say the starter is not drawing current.

Either buggered solenoid, or the brushes are worn out,
but usually worn brushes stop the solenoid from pulling in too.

More tests needed.


You need to measure the voltage between the two large terminals on the starter solenoid.

Should be battery voltage, and drop to less than 1V when you turn the key to start.

[jayray]

I measured the battery voltage while cranking on a freshly charged battery. Dropped from 13.4 to 11.4 V iirc.

When I was measuring that voltage at the wire for the solenoid it wasn't plugged into the starter. I would guess that the solenoid draws fairly low current so there shouldn't be a much lower voltage at the solenoid when everything is plugged in?

I've just taken the starter apart and cleaned the end bushes a bit, popped some motor oil in and it cranked over fine. Should have done it more thoroughly but needed it going for a run out to kaikoura today.

[matt dunn]

I would guess that the solenoid draws fairly low current so there shouldn't be a much lower voltage at the solenoid when everything is plugged in?

that's incorrect, expect about 30-40 amps draw on that wire inital current,
the later reduction types are closer to 70A !!!

mearuring anything without the circuit loaded is a waste of time.