No spark

[Steve L]

First of all, I checked the archive.

Second, is anyone really such a fanatic that he is surfing in the forum instead of celebrating Easter with his family and friends?

I am trying to start my Westfield with a 1.6 L Kent engine after a 5-month lay up.

There is no spark. I pulled one plug and laid it on the valve cover so that it was grounded and can see no spark when I crank the engine.

It has an absolutely primitive ignition system with a coil, a mechanical-advance distributor (no vacuum) and mechanical breaker contacts.

Here is what I have done to check:

12V at primary coil circuit.

Contacts set to 0.024 inch (spec is 0.025, but I don’t have a feeler gauge of that thickness).

Dwell set to 50 degrees. (spec is 48-52 deg.)

Timing set statically to 10 deg. BTDC.

I set the timing by first turning the crankshaft until the pulley marking aligns at the timing mark. Then I loosened the distributor housing and turned it until I could see according to the volt meter that the contacts open.

I have looked closely at the contacts to see if a spark jumps. This seems to be the problem: mostly there is no visible spark although the volt meter jumps. Occasionally I can see or here a weak spark.

I do not have a battery acid tester, but I did have the battery on a trickle charger for days and the charger indicates a full charge. The engine cranks well, and I would have thought if there is enough amperage in the battery to crank strongly, there must be enough to create a good spark.

The coil is nearly new. I bought it last September and drove the car only two months before parking it for the winter. The car started easily and ran well to the day I parked it.

I have the feeling the problem must be the battery, but the charger says it is okay.

Anyone have any ideas?

Thanks in advance.

Steve in Germany

[stu999]

Steve, if the engine is spinning over, there is plenty of voltage - that won't be the problem.

If it was running before it was 'laid up', it is probably corrosion on the points contacts. Get a small piece of fine wet/dry paper folded so that the abrasive is on both sides, slide it between the opened points, and let them close up on the paper. Then pull the paper out. Do this a few times, should clean them up good enough to run.

Put the coil lead (the dizzy end) close to something metal. Then, with the igniton on and the points closed, open/close the points with a felt tip pen, piece of wood etc. You can use a screwdriver, but make sure you onlu touch the moving side of the points, or they will earth out and give you a false result. The points should spark, but more importantly, so should the coil lead.

If the points are sparking, but the coil lead isn't, there is a fault between the dizzy and coil HT lead. Make yourself a temporary earth lead from a piece of wire. Remove the wire from the coil that goes to the points, and with the ignition on, 'flash' the temporary wire onto the coil terminal. This should create a spark from the coil lead. If it doesnt, coil or HT lead is poorly.

HTH Stu.

[Steve L]

Hi Stu,

thanks for the tip. Will give it a try tomorrow if not this afternoon.

Can you, or anyone for that matter, explain why I can't see a spark on the contacts but the voltmeter registers their opening and closing?

I am not much of an electrician, but my guess is that although 12 Volts are indicated, there is not enough amperage to make a spark jump. I had thought that the battery might be too weak (as I mentioned) but does that mean the points can have a good enough connection to conduct electricity but nevertheless are corroded enough to be ineffective?

Steve

[stu999]

Hi Stu,

thanks for the tip. Will give it a try tomorrow if not this afternoon.

Can you, or anyone for that matter, explain why I can't see a spark on the contacts but the voltmeter registers their opening and closing?

I am not much of an electrician, but my guess is that although 12 Volts are indicated, there is not enough amperage to make a spark jump. I had thought that the battery might be too weak (as I mentioned) but does that mean the points can have a good enough connection to conduct electricity but nevertheless are corroded enough to be ineffective?

Steve

Spot on... On good old clockwork ignition, it is usually best to diagnose on what you see, rather than what meters etc are telling you...

[YouMustBeJoking]

Condensers can fail and prevent a spark.  Points get changed but the condenser is frequently forgotten.

[smithydar]

ditto  for the condensor...for a few quid both the points and condensor can be replaced..worth doing then you know where you are.

darren  

[Steve L]

Hi,

I can report partial success - I filed the points, reset them and reset the timing. Now I get good sparks when I go directly from the coil lead to the valve cover. But when I pull all the plugs and try cranking the engine, got a spark only on No. 2 cylinder consistantly and occasionally on No.1. First I tried each plug on the No.2 cable and each sparked. Then I tried each cable on the No.2 connection on the distributor cap. The others still didn't spark. It makes me think that the wires must be bad, but I just had new silicon wires made up for me by a very knowledgeable mechanic last September and ran them for 2 months, and it ran quite well.

By the way, the coil, condensor and points were all new last September.

I check each cable for open circuit, but they all showed no resistance with the ohm meter. But as I already discovered, meters register one thing and practical application shows another. Is it possible to "bench test" cables? If so, my idea at the moment it to bring the cables back to the man that made them and ask him to check them. The only other components which I did not renew last fall are the distributor cap and rotor. I checked the rotor, which shows no wear, and the cap. I could not see any cracks in the cap, but there are burn marks in the plastic following each contact (they were they last year already).

So, can the mechanic test cables other than what I already did?

Thanks in advance, Steve

[stu999]

But when I pull all the plugs and try cranking the engine, got a spark only on No. 2 cylinder consistantly and occasionally on No.1. First I tried each plug on the No.2 cable and each sparked. Then I tried each cable on the No.2 connection on the distributor cap. The others still didn't spark.

I think you have a good diagnosis there Steve. New leads, and possibly a dizzy cap (especially if it is a Bosch one) should do the trick by thge sounds of it...

They can be 'load' tested, but TBH the test you have done would be conclusive enough for me to spend some money...  

[Blatman]

I just had new silicon wires made up for me by a very knowledgeable mechanic last September and ran them for 2 months, and it ran quite well.

conclusive enough for me to spend some money...

I'd be looking for some free replacements because these leads are apparently only 6 months old. Don't spend *any* money...

[Steve L]

Exactly my thought.

Just called the garage that did the work. They will check cables and dist. cap. If the cables are the problem, the garage will replace or repair them, no charge. If it is the cap, I will buy one from them.

(Can you believe this: if I go to the Ford dealer, the parts man *always* asks for the vehicle number. Since I don't have one, he can't look up the part. He just tells me, can't just go pick one off the shelf. Has to have the bin number. I go to a specialist garage, tell him I have a Kent engine and the man can set the part on the counter.)

Thanks for your support.

Steve