Post by canuck on Jul 7, 2019 15:59:37 GMT
I thought to share this with you lot.
I was thinking it time for a new distributor cap. I still use the 'correct' side entry style with screws for the HT leads. I bought a cap from a respected MGA outlet.
Sadly these new distributor caps are not as once were.
Evidently this issue was well known to the MGA crowd and is documented on MGA Guru site, however I was not aware.
The issue is with the type of screw used in these new design caps. These caps can be either Lucas green box packaged or white box packaged, and I am lead to believe this is probably a single source item. The supply chain is most likely polluted with this style cap now.
See pictures below;
the type of screw used is not shouldered, as the OE Lucas was and the end is too blunt.
What happens is when one tightens the screw to pierce the HT lead it crushes the lead before piecing. One then continues to snug it up expecting some resistance to let you know it has done its job.
Well in my case I ended up over tightening and damaging the top of the cap. Yikes!
FWIW the vendor replaced the cap FOC.
So to use this new cap and have it connect to the HT leads as designed. I suggest increasing the angle one the tip of the screw; a bench grinder makes quick work of this. As well measure the distance to pierce the wire and don't over tighten as I did.
I guess one could write this off to me being ham-fisted? but the OE Lucas cap/screw design would never have allowed this.
The OE screws seem to match the thread in the new cap but of course the design of the brass terminal does not have a shoulder for the screw to stop against. Over tightening with the OE type screw in a new cap is still possible.
Despite the frequent belly aching and bad press festooned on the Prince of Darkness at least there was quality and apparently knew how to design electrical bits.
What would we need to do to have this back again?
Bruce
I was thinking it time for a new distributor cap. I still use the 'correct' side entry style with screws for the HT leads. I bought a cap from a respected MGA outlet.
Sadly these new distributor caps are not as once were.
Evidently this issue was well known to the MGA crowd and is documented on MGA Guru site, however I was not aware. The issue is with the type of screw used in these new design caps. These caps can be either Lucas green box packaged or white box packaged, and I am lead to believe this is probably a single source item. The supply chain is most likely polluted with this style cap now.
See pictures below;
the type of screw used is not shouldered, as the OE Lucas was and the end is too blunt.
What happens is when one tightens the screw to pierce the HT lead it crushes the lead before piecing. One then continues to snug it up expecting some resistance to let you know it has done its job.
Well in my case I ended up over tightening and damaging the top of the cap. Yikes!
FWIW the vendor replaced the cap FOC.
So to use this new cap and have it connect to the HT leads as designed. I suggest increasing the angle one the tip of the screw; a bench grinder makes quick work of this. As well measure the distance to pierce the wire and don't over tighten as I did.
I guess one could write this off to me being ham-fisted? but the OE Lucas cap/screw design would never have allowed this.
The OE screws seem to match the thread in the new cap but of course the design of the brass terminal does not have a shoulder for the screw to stop against. Over tightening with the OE type screw in a new cap is still possible.
Despite the frequent belly aching and bad press festooned on the Prince of Darkness at least there was quality and apparently knew how to design electrical bits.
What would we need to do to have this back again?
Bruce
