Technical non starter

[Karletto]

1x per week it happens that our uno doesn't start. there are no sounds from starter motor. i can hear fuel pump and all lights work OK. the battery is new. warm or cold doesn't metter and jumping cables doesn't help. battery cables are OK and not corroded. after x turns of the ignition key it starts with no problem.
i suspect it's the ignition below steering wheel because ->

i found out that kids used fuel from poor uno to fill thair motorbike. becouse thay couldn't suck it out directly from the tank thay used some fuel hose from engine bay and put it in plastic bottle. thay didn't wire the fuel pump directly with the battery so thay could have had non-stop fuel flow but thay used ignition key instead. of course in order to fill few bottles thay needed to turn the key at least 50 times :doh:

so is it the ignition below steering wheel?? starter motor was renovated few months ago

 

[alexGS]

so is it the ignition below steering wheel?? starter motor was renovated few months ago

Until the last sentence I would have said 'starter motor brushes', but as you said, it does sound like it's the ignition switch instead. It's easy enough to remove the ignition switch - don't try to remove the lock, just push in small tabs to extract the plastic-bodied switch from the back of the round lock housing.

There are several ignition switches in use on the Uno (dark red plastic, black plastic, etc) so make sure a replacement turns through the same angle and looks similar. If you get the wrong one, things come on at the wrong time and some accessories (e.g. wipers, heater fan) won't go when the key is in the 'On' position, but work if you turn the key back towards 'Off' a little bit - which is no good.

You could also try cleaning the switch contacts, but the casings are often rivetted together, so that could be a fiddly job. This is one part of the car that you DO want to be reliable.

Also, check that the starter motor small push-on terminal has not simply fallen off or worked loose - it's quite vulnerable - and maybe use a jumper cable to make a temporary connection from the battery positive to the small terminal just to make sure the starter motor works every time - before you go any further with the ignition switch. Which engine are we talking about here? FIRE engines have the starter motor on the back, while 1116cc/1299cc/1301cc/1372cc have the starter on the front (and therefore, more likely for the push-on wire to be knocked off or to get oily and dirty).

PS. It's probably better that the kids didn't hot-wire the petrol pump, as that could have damaged the control relay or led to a dangerous pump-running-all-the-time situation But it does make me wonder which Uno you have - I'm now guessing an injected version which could be a 999/1108cc FIRE or a 1372cc. Carburettor Unos have a mechanical pump.

PPS. Another off-the wall guess If it's a Selecta (!) - well they did make them with the i.e. engines - perhaps it's the inhibitor switch that closes when the selector is in P or N. I don't know if this is on the transmission or the selector lever (I've never seen one), but it will be somewhere - if it needs repositioning or cleaning, it could prevent the engine from starting.

-Alex

 

[Karletto]

today a new symptom appeared and could be related.
it was hard to start the engine. it needed the throttle in order to start. after starting the engine it still needed throttle or else it would die. when the engine is hot it doesn't need throttle in order to start.

than i drove 6 miles and stopped. after 1hour it started great and drove back 6miles to gas station where it started great too. than i drove 0.3 miles but it was absolutely dead when starting/ same as in 1st post.

UNO fire 999ccm