Misfire issues kinglead to coil

[A KIRK]

Right thanks to doug I now have the engine in and running sort off, but it seems an old fault has returned to upset me.

Engine runs, but every now and then you can see the king lead arking back across the top of the coil. Now I have tried a new lead, and the coil is new as well, I also tried the old coil.

We think we have narrowed it down to a wireing fault in the loom or the amplifier is iffy.

So what I;m after is has anyone else had this issue?

As far as I;m aware the idle control (green Box thingy) is working well, as fault is still there when you bypass this

Thanks for any assistance

[bigherb]

If the the coil is tracking out then the problem is from the coil to the spark plugs. Nothing wrong with the amplifier ect as they have done their job and produced a spark. Check for a crack or dirt around the coil tower or the rotor arm resistor has burnt out, HT leads have too much resistance, spark plug gaps to wide etc.

[ghost123uk]

Yep, not the ign amp.

As you have replaced the coil and kinglead (with new ?) it cannot be them.

So next is (as has been said above) the Rotor arm but also could be the Dizzy Cap.

Explanation = The spark is trying to find the easiest path to earth.
This should be to the spark plugs, but if there is a problem restricting the flow to the plugs, the next shortest path could be across the top of the coil to the coils metal casing.

I have to say though, that 99% of the time this fault would be a faulty kinglead.

p.s. You do have the correct type of leads for your dizzy cap ?
There are two types.
A "peg" in the cap that mates to a socket in the lead.
And a simple socket in the cap that a metal sleeve on the end of the lead mates into.

[bigherb]

Yep, not the ign amp.

As you have replaced the coil and kinglead (with new ?) it cannot be them.

Never assume anything.

[ghost123uk]

Yep, not the ign amp.

As you have replaced the coil and kinglead (with new ?) it cannot be them.

Never assume anything.

True, even new parts can be faulty !

Did you buy them off JK

[A KIRK]

Right hello chaps, I might have solved this issue but not 100% sure yet till I look again tomorrow.

I have replaced the leads with a new set and replaced the rotor cap, haven't done the arm yet, as couldn't get one earlier.

It doesn't appear to be arking out on the coil anymore.

Can't get the damn thing to idle now, won't have any of it, will have another play tomorrow.

Cheers chaps

[A KIRK]

Right ok back to square one, been out for a little test drive, thought all was ok, but no its back to sparking accross the kinglead- positive terminal on the coil.

So for now I;ve ordered a new rotor arm, as couldn't get one yesterday.

When I get a few minutes tomorrow I'll double check the spark plug gaps.

So far it has new:
Rotory cap for a CT dual vac dizzy
new HT leads
new plugs short reach as it now has beetle heads (will check the gapping tomorrow)
New coil well couple of months old

I'll update you all as soon as I get any further with it

Cheers


Ok managed to get a little time on it tonight.

All spark plug gaps are correct, now I had a little idea (bad idea) that maybe I shouldn't have removed the nuts on the end of the spark plugs, so I put them on again, problem being that they don't sit/locate in the ht leads, but it did short term ressolve the short, and the van drove fine until the leads started to part company with the plugs, and hey presto I was back to have a short.

SO I shall have to have more of a play once I get the new dizzy arm

[A KIRK]

Right ok an update after putting new:
plugs
Leads
Dizzy cap
Dizzy arm
ignition amp
Another earthing point to the engine block to the chassis

It would seem that there was a hairline crack in my newish coil (which I must have missed), I dug out an old one which I had for the engine, and replaced it with that, and all seems to be ok for now. Have only done 14 miles so far, so a little more testing is required yet to confirm that its gone.

Slowly getting there, but seem to be spending more time walking away from the van than working on it at the moment.

Thanks to everyone for their help, especially Doug who has been out twice

Cheers

[dugwiththevwbug]

thats great news andy how small was that crack i missed it myself and had the coil off to have a look aswell.

the pinking is pre-detonation try retarding the distributor a tad ie 6 degs btdc instead of 7.5 may help.
good luck and i hope you finally nail it soon
regards doug

[dugcati]

thats great news andy how small was that crack i missed it myself and had the coil off to have a look aswell.

the pinking is pre-detonation try retarding the distributor a tad ie 6 degs atdc instead of five may help.
good luck and i hope you finally nail it soon
regards doug

blimey - if your getting pinking on std timing then I would think summats amiss - does it have the right dizzy on/is-are the vac pipes all on correctly and is the carb setup right?

[dugwiththevwbug]

blimey - if your getting pinking on std timing then I would think summats amiss - does it have the right dizzy on/is-are the vac pipes all on correctly and is the carb setup right?

theirs a good chance Andy that the timing will be out as was set up when the ht lead short was in place and the other electrical wear issues. Now you have a healthy spark the engine will be in a different state of tune with a knock on to the timing position. Because the engine is running more smoothly the vacumn advance will be stonger and thus over advancing (pre detonating)at higher revs.
regards doug

[A KIRK]

As far as I am aware it has the correct dizzy twin vac original bosch unitm vac pipes are definately in the correct order, and carb was set up right before the last engine self destructed, I did take it out agin last night but I mistakenly advanced the dizzy which made it worse,

Tomorrow U shall retarding it slightly its possible the dixxy was 100% in the correct position to start of with as we did move it a little.

To be honest I;m loosin the will with this van now, much more and it will be up for sale and I'll go down the tranny route

[A KIRK]

Looks likie we crossed posts there. What you wrote is what I was thinking when I went to bed last night. I'm hoping to get some time on it again tomorrow evening.

[A KIRK]

The old girl is finally running spot on, the final issue was the timing was wrong as we set it when I had the elcetrical fault, so I retarded it, saw Doug this morning and she is now fit and ready for her travels.

Cheers Doug for your help with this

Andrew

[dugwiththevwbug]

No worries andy anytime
glad its there at last. At least now you have the heads and pistons you should have had on your recon to start with nudge nudge wink wink