No spark

[ukkaapie]

Hi,

I have now found out where to carry on looking as my T25 1.9 fuel engine is turning over but not starting. I suspected electrical initially as the engine didn't even try to start.

I took the middle HT lead off the distributor cap and placed the metal point about 2mm from the manifold. Got a friend of mine to turn the engine and no spark. I took a lead from one of the spark plugs, just to make sure, and still no spark (the battery is now starting to run down some so it does not turn as fast)

I have a intermotor 11480 coil installed that was supposedly last checked in 09/09 (according to the label underneath). I cannot find any information on this site or any website relating to the resistance of the primary or secondary coil.

I have taken some measurements and have the following:

Primary coil (tested from + to -): 1.2 ohms
Secondary coil (test from middle HT lead to +): 4.44 K ohms

Is this correct? Can anyone tell me if I should be replacing the coil? There is 12v to the coil.

Is there any way to test the control unit and does anyone know where I can get a control unit from if necessary?

Thanks guys...

[kevtherev]

No spark means the hall sender has failed
search "hall sender" for more info

[ukkaapie]

Woo hoo... she started today for the first time...

I did a check to make sure the coil is working. Performed the test recommened by bigherb:

The hall sender is simple to check just remove the centre HT lead from the distributor and hold it about 5mm away from a metal part of the engine or bodywork and away from the fuel system, remove the three pin plug from the distributor and probe a piece of wire into the centre pin of the plug, switch on the ignition and then scrape the other end of the wire along a metal part of the engine this should then produce sparks from the HT lead, if you get sparks then the rest of the ignition system is OK and the hall sensor is at fault. before you replace the sensor check there is more than 5 volt across the two outside pins of the three pin plug.

I measured 9v across the outside two pins and did generate a nice spark. I then plugged the connector back in and thought, what the hell, let's try turning her again and lo and behold she eventually took. Idled her for about 5 minutes then switched her off.

Packed the tools nicely, cleaned the area a bit and tried her again. Started first time.

I am not sure whether this means the hall sender connections were bad or whether the hall sender is on the way out but at least I managed to start her.

Thanks kevtherev for pointing me in the right direction and thanks to everyone on this forum just for being available to help.

Will keep posting my experiences with this in the hope it helps someone else.

[ukkaapie]

And so we back to being stuck in the driveway again.

Went to take her for a drive and now she does not want to start. Did the test for spark, as I did before with the wire, and a spark is generated but still no starting.

Looks like am going to have to replace the hall sensor.

Does anyone know where I can get one from. I am in Bournemouth.

[ukkaapie]

What I don't understand is that she started. Then she didn't, then she did and now she doesn't again.

I mean everything is pointing to the hall sensor but surely the sensor doesn't gradually break down. Does it?

[kevtherev]

Woah hold on.
lets eliminate the simple first.

ensure the battery is properly charged up.
ensure that the coil is correct for the ignition system.


no spark from the king lead ...If there is no spark direct from the coil the hall sender is at fault
Without a signal from this the ECU doesn't know the crankshaft position to send a spark.

you have the correct supply voltage and a good earth to the coil and the hall sender is giving you a trigger signal and the coil is a known good unit there are few options left.
I would then consider the ECU.... or wiring to/from the ECU is faulty.

but my moneys on the sender.... or wiring concerned with it...None or intermittent or poor spark is a symptom

[ukkaapie]

H Kev,

The engine is turning over nicely at the moment. Better than it did earlier when she did start so I am assuming the battery, while not great, is sufficient. I get a nice spark generated using bigherb's method of testing for spark.

I need a hand with testing for spark so will wait for my mate to come along. Can use his car and jumper leads too if necessary. I have more of an understanding now of how the system fits together now so have a better idea what to look for.

I assume if I test for spark on the centre ht lead and get none this means the sender unit is gone?

I see breakyard.com and justkampers.com do the hall sender unit. Are these guys ok? I have seen some conflicting reports in the forums about these shops so not sure what to expect.

[kevtherev]

Brickwerks is the one to get.
however it's a non return policy on this item and it is not cheap.

be sure as hell it is what you think it is.. try to borrow one off a pal or another member just to be utterly certain

[ukkaapie]

Nice one. Waiting to hear back from them on a quote.

I performed another test where I pulled back the rubber sleave and tested between pin 1 & 2 with the iginition on. I got about 1.4V and rocked the car so that the crank wheel turn one full turn. The voltage never changed.

Is this an indication of a faulty hall sender?

[bigherb]

Nice one. Waiting to hear back from them on a quote.

I performed another test where I pulled back the rubber sleave and tested between pin 1 & 2 with the iginition on. I got about 1.4V and rocked the car so that the crank wheel turn one full turn. The voltage never changed.

Is this an indication of a faulty hall sender?

Yep

[ukkaapie]

Thanks bigherb.

Is there a reason why the hall sender would suddenly start working and then fail again?

[BOXY]

The Hall sensor is just a magnetic switch. Mechanically there isn't much to go wrong with it, but there are three small wires that connect it to the plug on the side of the dizzie. If one of these wires broken inside the insulation or the connection at either end is iffy it could lead to an intermitant fault. Here's a post from when I was testing mine.

https://club8090.co.uk/forum/viewtopic.p ... ilit=+hall" onclick="window.open(this.href);return false;

In the end I left my 009 dizzie fitted but one day I'll get around to trying to get the electronic ignition working again.

[kevtherev]

great link Boxy and a good picture

[ukkaapie]

Ok guys, have removed the distributor and taken out the first circlip.

I am having trouble removing the vane off the shaft. It seems quite stuck. Have tried using 2 screwdrivers to lift it off but it will not budge.

Is it supposed to not come off easily? I am worried about bending it. Maybe is a good idea to replace the whole distributor?

[BOXY]

It has been while since I took a dizzie to pieces but I think there's a locking pin that fits down in-line with the dizzie shaft. You need to get it out with long-nosed pliers before trying to get the vane off. I'll have a look it my garage later and see if I've still got the dizzie stripped down and take a photo.