6 replies to this topic

[Lillyput]

In the process of reviving a neglected and abused 1967 Cooper S. Sorting through many strange previous owner modifications, scorched wiring and cob jobs -- for example the horn operated off an old wiper switch mounted under the dash, which apparently got it through the state safety inspection -- you have to have an operating horn, but the rules don't say how it needs to be operated.

 

The car is fitted with a distributor that has a Aldon sticker.

 

When I pulled the dizzy I learned that it is based on a Lucas 45D4. But I cannot find out any additional information -- such as is the advance curve matched to this car's destiny as a Sunday driver?

 

The housing has hand engraved markings: "100AY" and "3/00." (I can't figure out how to submit an image -- "My Media" icon doesn't seem to be working for me as a way to attach photos.)

 

Here are my three questions:

1) What might these markings mean?

2) What was the correct factory supplied distributor for this car?

3) What does Aldon do to Lucas distributors that makes them an upgrade from stock?

 

As for background, forty years ago, in my wastrel youth, I simultaneously ran a 1959 Sprite, a 1960 Mini, a 1962 MKII Jaguar, and a 1967 MGB-GT. So I am no stranger to SU carbs, BMC engines, and Lucas electrics, but I can't get this car to run right. Having ruled out carb issues, I am left to suspect underlying ignition issues. Checked timing, point gap, new wires and rotor... Cannot rule out faulty distributor, but don't know anything about this one -- all searches seem to lead to "for sale" items or general tuning advice. The Aldon website was not helpful.

 

Thanks in advance for any light you can shed on this subject.

 

 

 

 

 

[imack]

Lucas 45d4 was the distributor fitted to minis after 1974 and continued into the 80's. It's a straight swap for the original 23d4.
Aldon 100AY is the "yellow" spec advance curve designed to work with fast road and rally spec cams in A series engines.
A 100AY+ would be the same advance curve but with a drive and clamp area designed to fit it to an A+ engine.
A lot of these distributors don't have a vacuum advance system.

[Earwax]

Sorry for not answering your actual question - i have no idea of what Aldon specs are BUT I would recommend measuring what its current curve is.

 

If you have a dial back light - i would suggest timing at idle , 2000,   3000 and say 5000 ( more than 4000 anyway) - I have seen an ALDON Yellow that kept adding more timing at 4000 ( 38 degrees plus )

 

***note the caution applies to lots of dizzies not presenting with what the curve was supposed to be - so not Brand specific)

 

Before potentially spending $$ on items that may or not be contributing to this issue I would Check resistance on leads and gap plugs etc 

 

I would ask around to see if you can swap in a known working dizzy ( with their leads)  just for diagnosis ( not perfect for your tune but you will easily spot if it makes a difference)

 

Now you will again slowly have to aquire another mini and then another to help with swapping parts out and in -  enjoy the beastie when you get it sorted.

 

 

Good luck

[nicklouse]

Also have a look inside a# to what the bob weights have stamped on them. 
 

some were fitted to Minis others were not. 
 

mine was modified to work with my build.

[Spider]

There's a bit of info here on what the actual curves are for the Aldon Dissys;-

 

https://www.theminif...advance-curves/

 

More importantly though, I would suggest finding out what curve your engine actually needs. There was and still seems to be a period when people bought this stuff and fitted it expecting to get an extra 50 HP when in the case of these distributors, while good, are suited for a specific application.

[Lillyput]

thanks imack, earwax, nicklouse and spider. Your comments track with my suspicions. I am aware of a table for advance curves and think I will now pursue a MK1 appropriate non-performance dizzy AFTER I replace the cap and condenser. In my ignorance, I ordered parts for 23D4. So I have replaced the leads and rotor... Will replace the affordable bits before taking any deeper plunge.

 

Back in the '70's/80's I had parts in boxes from a junked AH Sprite and a junked MGB so I could always grab something and test by substitution. Alas, long gone.

[68+86auto]

Someone could have modified the advance curve to what you need (or made it worse). Get it tested and recurved to what you need.

Even if you buy another distributor you will need to get it tested.

Jeff Schlemmer (Advanced Distributors) is one of many people who can do so in the USA.

Edited by 68+86auto, 25 November 2024 - 02:54 AM.