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March 16th, 2025

Distributor

The distributor in this car was a four-banger version of the ubiquitous Lucas 25D type, used in a wide range of applications of this era and beyond.  My unit was a little dirty, but generally looked good.




On checking the spindle condition and fit, I was surprised at how little evidence there was of any significant wear.




Then I realized why.  I'm pretty certain this is a date code, indicating the distributor was made in the Fall of 1973.  I was doing some engine work on the car in '74, so it was certainly me that bought and installed it.  I checked some old records I still have for some reason, and sure enough, I bought this distributor in April, 1974 from Moss for $25.10.  And since the car went into storage in '75, this is essentially still a brand new distributor.




This simplified things a lot.

Since I had everything apart, I took a close look at the body.  Back in the 70s, I would have tried to polish this part, and it showed.  It might have looked pretty good back then, but pot metal doesn't keep a shine very well over the long term.




This time around, I just did a light blast for some tooth, and a powder coat.




Then put everything back together using original parts.  I think even the points and condenser are probably fine, but I have spares if they aren't.




Then, I came to the vacuum capsule.  I assume it came with the distributor, but looked a lot worse, with significant corrosion.




I wondered if the internals had aged well.  It did respond to a vacuum, but a more definitive test seemed like a good idea.  There were many different capsules available for these distributors, with different response characteristics to the vacuum signal.  The marking on this capsule was 7-14-10, meaning that the advance should start at 7 inches of mercury, and max out at 10 cam degrees of advance at 14 inches of vacuum.

A simple test setup could tell me if the unit performed close to those specs.




This was the result:




Now, no one really expects these devices to be dead-on accurate to their specs, but this seems to be off by more than simple tolerance.  The total advance is fine, but it seems to start coming in a little too soon.  Before I worry too much about this, I need to land on what other mods I'll be doing to this engine.

So, I cleaned up the capsule and installed it, partly to make sure that those tiny parts didn't walk off.




The cap latch arms were pretty crusty, so they got cleaned up, powder coated, and re-mounted with new rivets.




I removed the wires from the cap, and won't replace them until the distributor gets mounted on the engine.  I like to do custom lengths of ignition wires for a neater appearance.




Last up was the distributor clamp, which was pretty corroded, and probably original to the car.




Stripped the rust and the old zinc, and replated.  One thing of note--that clamp bolt, which looks like 1/4-28, isn't.  It's 1/4-26 (a BSC thread).  Those Brits sure do like their odd-ball threads.




On the shelf with this puppy.




This was a quick one.  Pretty much just one day and no significant cost.

Comments to Ed at elhollin1@yahoo.com.

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