Help with checking for a spark!

[guymcc]

Having a few problems getting the car to start. How do I go about checking for a spark. I've checked with a screwdriver in the lead and holding it near the top of the engine cover, on the nut that holds it down, and there was no spark, am I doing this wrong, or correct and there actually isn't a spark, and if so then how do I test further down the line as it were for the spark?

I've turned the engine over whilst the dizzy cap is off and I can see a spark at the gap.

Any help would be great!

[beero]

Take the central lead off the distributor ( lead from the coil) and hold that near the cylinder head and see if it sparks when you turn the engine over. You will need some rubber gloves or you will FEEL the spark. Let us know what happens.

It may be the coil (tee hee! )

[tysonn]

Never!

[guymcc]

Take the central lead off the distributor ( lead from the coil) and hold that near the cylinder head and see if it sparks when you turn the engine over. You will need some rubber gloves or you will FEEL the spark. Let us know what happens.

It may be the coil (tee hee! )

Ok will do thanks! If I don't get a spark, what would be the next thing to check? And if I do get a spark, does that mean that it's something to do with the distributor?

[kennatt]

First.... you need to check that power is getting to the distributor,if you haven't got a meter or test lamp take top off dizzy,take rotor arm off so you can see the contacts in the points if they are open turn the engine untill they are closed,then with ign on get an insulated screwdriver or other wooden or plastic implement and flick the points open if there is power you will see a small spark as they open..................Then take king lead out of dizzy cap making sure the other end it still in the coil and hold it close to the engine block preferably with insulated pliers ....flick the points open again and you should see a fat loud spark jump from the lead to the block this indicates that the coil is getting power and is working. If both of these test produce a spark turn the engine and watch the points just to make sure that they open at each of the high points on the rotor. ,still holding the lead near the block ,turn engine over by hand, It helps if you take the plugs out you can then turn it by the fan blade,and see if you still get good spark from lead to block this indicates that the ignition/dizzy system is sound ie points, rotor arm,coil and leads are sound, If all the above is ok than problem lies elswhere Fuel/carb /pump. Doing it this way will quickly indicate where the fault is,if any, and you can back track from there,if you turn the engine over a few times don't be fooled by the spark getting weaker and fading away its because the coil (Basicaly a capacitor) is becoming discharged,thats normal. Its never the coil anyway

[guymcc]

Thanks Kennatt! That has helped a lot.

Before reading your post I popped out to the garage and tested the lead from the coil against the block, and there was a spark. I tested it by turning the engine over using the button on the bottom of the solenoid. So I then tested the spark plugs against the block and they also all sparked.

I'm going to have another look at my points gap, as I adjusted it yesterday to make the gap smaller but I think I've used the wrong screw to make the adjustment. I used the screw clearly visible in this photo. This was the gap before I adjusted it smaller.
I believe there is another screw/place where the gap adjustment should be made??

[MarkyB]

The gap does look a bit wide, the heel doesn't appear to be resting on the cam but that might just be a shadow.
You probably need to slacken the cross-head screw as well as the big plain one to adjust the points gap.

[guymcc]

I have managed to reduce the gap using the flat head screw. Not sure what the philips does tbh. Probably worth noting that my traveller is a '67 my so would i be correct in saying that this distributor is the later type?

[Trickydicky]

The phillips screw secures the condensor, its the flat headed on that adjusts the points.
I would take the points out completly and check that they are not pitted, if they are then replace them.
If you do need to replace the points and all was running well before you started adjusting them, leave the condensor in place as the new ones are very poor quality.

[kennatt]

well assuming that nothing else has been touched and you are getting a spark at the plugs it should start,unless its starved of petrol pour an egg cup full into the throat of the carb,filter off. And if it starts and runs for a few seconds then its fuel ... carb or pump.Is the pump ticking.

[katy]

Possible bad rotor arm.

[kennatt]

Possible bad rotor arm.

yes but hes got a spark at the plugs.

[guymcc]

Good news!!

Had a good tinker this afternoon with a friend who came round who's an ex mechanic. We went through the basics and double checked the leads and timing/firing order, all seemed fine.

We turned the engine over without the spark plugs in, this would perhaps 'blow' anything out.

Put everything back together and agreed that with a spark and the smell of fuel on the spark plugs then we must be close. Gave the plugs a quick clean up and spray with some brake fluid cleaner and popped them back in.

Turned her over and just as we gave up in that particular crank, she had a cough!

Tried her again and this time she fired up!!

Ran her for a bit, and every thing seemed ok. Maybe a bit smokey!

Just been back out to her to refit the brake servo that had to come off to get the starter motor replaced and she fired up first turn no probs!

So going to have a search mow as to how to bleed the brake system after the pipes have been off at the servo. Will i have to do each corner in turn?

Thanks for all the help so far....very happy!

[namass1]

I have a spark problem but it doesn't appear to be covered by these excellent tips.I can get no spark at the points of my mm at all.I have replaced the points, plugs, condenser and coil with new parts, but if I turn on the ignition and open the points with a screwdriver there is nothing there at all.The car has not run for a couple of years and when it last ran, it started o.k. but since it's 'rest' it doesn't want to play ball.Can you help?

[bmcecosse]

Is there any power at the lead TO the coil? Then check if that power still shows at the lead TO the dizzy. If that's ok - then the points are maybe wrongly assembled or the little 'low volts' wire inside the dizzy is trapped or broken....

[namass1]

The coil is brand new but there is no spark at the points and when I pulled the lead out from the distributor and held it against the block and turned the engine there was no spark there either. There is power getting to the coil, though.

[bmcecosse]

Which lead did you pull from the dizzy....the 'king' HT lead?