Distributor Caps woes

[octo0072000]

if you was fouling plugs at 25 thou sounds like you need a hotter plug plugs always used to gap at 25thou in the old days and yours is an old motor
would be tempted to order a dizzy cap and rotor arm and condenser from the states

 

[ajlelectronics]

That can be a symptom of the wrong polarity on the ignition coil.

 

[Kayos]

Not exactly the same but years ago I used to do daft things like turbo Vauxhall 8v engines, using the GM philosophy I obtained various stand alone ignition systems and used them on my conversions

I found dizzy caps and rotor arms took a serious nose dive in quality, even good makes were just rubbish and didn't last. As has been said, can you buy direct from the USA? At least you can rule out quality in that wsy

 

[Shox Dr]

So just to recap.

In line 6cyl 4ltr
12v system
Pertronix ingintor II (1168ls) contactless points (NO ballast resistor required)
Pertronix 3ohm flame thrower coil.
Standard parts cap and rotor
Copper HT leads
NGK B-4 30thou gap
Timed tdc

Cut the dizzy in half tonight. You can see the centre carbon erosion.
Tried the cut down cap on the distributor looks to be round 10thou gap

 

[ajlelectronics]

So just to recap.

In line 6cyl 4ltr
12v system
Pertronix ingintor II (1168ls) contactless points (NO ballast resistor required)
Pertronix 3ohm flame thrower coil.
Standard parts cap and rotor
Copper HT leads
NGK B-4 30thou gap
Timed tdc

Cut the dizzy in half tonight. You can see the centre carbon erosion.
Tried the cut down cap on the distributor looks to be round 10thou gap

View attachment 168250

Have you checked the coil polarity yet? That is typical of the coil being wrongly connected.

 

[Shox Dr]

Have you checked the coil polarity yet? That is typical of the coil being wrongly connected.

Yes I did thanks. It’s good.

 

[jsf55]

Have u got a ballast resistor handy ? put that in the 12v line going to the coil and see if that helps, have you checked the alty/ dynamo output? it's not over charging causing stuff to burn out ?

 

[Shox Dr]

Have u got a ballast resistor handy ? put that in the 12v line going to the coil and see if that helps, have you checked the alty/ dynamo output? it's not over charging causing stuff to burn out ?

Showing about 45amps with lights and blower running @ 13ish volts. I’ll stick a meter on tomorrow

 

[jsf55]

I definitely try a ballast resistor in the incoming feed to coil and see how that goes

 

[Shox Dr]

I definitely try a ballast resistor in the incoming feed to coil and see how that goes

Pertronix state not to use one

 

[jsf55]

How old are the copper leads ?

 

[Shox Dr]

18mths

 

[jsf55]

That might be the problem, I think someone else suggested this, it's about as much as I can find out, the ballast will help cut down on the amount of power going into the coil and help save the cap and rotor arm, but it's not going to be at full potential !

 

[zeppelin builder]

So just to recap.

In line 6cyl 4ltr
12v system
Pertronix ingintor II (1168ls) contactless points (NO ballast resistor required)
Pertronix 3ohm flame thrower coil.
Standard parts cap and rotor
Copper HT leads
NGK B-4 30thou gap
Timed tdc

Cut the dizzy in half tonight. You can see the centre carbon erosion.
Tried the cut down cap on the distributor looks to be round 10thou gap

View attachment 168250

looks like the brush is not in contact with the rotor arm and arcing rather than conveying the current is it loose enough

 

[Shox Dr]

looks like the brush is not in contact with the rotor arm and arcing rather than conveying the current is it loose enough

Looks like it doesnt it. However I checked to make sure there qas good contact .

 

[daedalusminos]

Is the carbon contact sprung or does it rely on the rotor arm contact for spring?

 

[Shox Dr]

Cap is not sprung.

 

[armalites]

I know the Series Land Rover owners have had loads of issues with distributor caps, rotor arms and condensers. There is a guy called Distributor Doctor who supplies good stuff that desn't have the issues. Not sure if he does stuff to suit your though

 

[RichardM]

Does it have a condenser?

If so try changing it, used to arc all over the place when my old British bikes condensers were failing.

 

[jsf55]

Cap is not sprung.

That's wrong, everything I've worked on either the cap carbon is sprung or the rotor arm has a sprung lever on the top, mismatch there somewhere ?