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ncbugeye project this weekend

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ncbugeye

ncbugeye

Jedi Warrior
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ncbugeye's SU AUF305 fuel pump has stalled on me four times in traffic in the last week, needing the traditional sharp tap with a wrench. I guess I should be glad the weather is nice enough round here to be driving an open-top car, still, in December. It's about like a July day in England. I've done over 100 miles in ncbugeye this week. I've been picking up my High-School Junior son from school, and it's quite cool to see how interested kids are in old cars like this. The girls giggle and point and chaff my son about it but he thinks it's pretty cool too.

Anyway, four times was about enough, so I contacted Dave Dubois through his page at https://www.custompistols.com/cars/dave/ddsu_fuel_pump_services.htm about rebuilding it and converting it to electronic. Turns out he is recovering from an injury and won't be able to do the job for a couple of months. So to fill the gap with a temporary fix, I wandered by my local Napa store and asked about Facet pumps. They had ONE in stock, and of course it's a negative earth pump, although, yes, it can be wired either way provided you wire it all the way to the battery. So this led me once more to the idea of converting ncbugeye to negative earth. I had earlier exchanged emails with Chris of Spridget-tech and he described how to do it.

So what are the reasons why one should or should not do this conversion?

I know there are some devices like alternators that are evidently only available in negative earth, but I have postponed the alternator conversion for a while, partly because I sort of like the antique mechanical rev counter even though its cable gets in the way of doing any work on the distributor.

I also know that the AUF305 is a positive-earth pump, so I'll have to have it converted to negative earth when Dave Dubois rebuilds it for me.

I know you have to switch the cables on the coil and "flash" the generator.

What else might I encounter?
 
That's it, that's all there is on a Bugeye. Not even sure you need to change coil wires. Heck it is a coil and is in the loom one way.

My understanding is flash the generator and you are good to go.
 
I take the plastic cap off, use a burnishing tool on the contacts and spray it down with wd-40. Moisture is a problem in this end of the country it seems..
 
So there's an F connector and a D connector on the Lucas dynamo. One is larger than the other. Which connector is which? It's been 34 years since I messed with one.
 
Hmm. your loom should have two different size connectors?
 
Yes, it does, but to "flash" it you have to do the trick with the F terminal
 
In all the years I have been in business, I have heard many versions on how to polarize a generator and voltage regulator. Some versions are correct, others are totally wrong.
Polarization is a procedure which matches the polarity for the generator and the voltage regulator. The majority of the vehicles are manufactured negative ground although some of the older vehicles were manufactured positive ground. The generator has to be set up for either polarity. The generator will charge either way, however the voltage regulator has only one polarity. Whenever the battery is disconnected from the vehicle for any reason the polarization procedure should be performed.
The recommendation on how to polarize a charging system is the following: After the installation of a battery, generator or voltage regulator follow these procedures. The terminals on the voltage regulator are labeled with letters and this is where you will do the polarizing procedure. Both of the components will have battery power so do not start the vehicle or turn on the ignition switch before polarizing them. You will need a small piece of wire fourteen or sixteen gauge with alligator clips on the ends. Find the "B" terminal on the regulator and attach one of the alligator clips, find the "D" terminal and touch the terminal with the other alligator clip. You can touch the terminals a few times and it will produce a soft light spark. Under no circumstances touch the "F" terminal or any other part of the regulator or you could damage the regulator.
For the Lucas voltage regulators that have the teminals labeled A1, A, F, D, E, the polarization procedure is the same however the terminals that will be used are the "D" terminal and either the "A" or "A1" depending on which teminal is used on the vehicle. Either terminal can be used if wires are going to both terminals.
Start the vehicle and you should see the red generator light go off on the instrument panel, you may have to rev the engine up a few RPM, generators have a tendency not to charge at idle speed. If you have a gauge on the instrument panel the gauge will respond accordingly.
Look for more technical information in the future on these page.

Sincerely,
Mike Martinez
 
This conflicts with what I have read elsewhere and what Chris of Spridget-tech told me. Aaarrrggghhhh!!!!!
 
Only other component I can think of not touched on with a Pos. to Neg. conversion is the fuel guage which must have the terminals reversed or it will read full when empty and visa-versa. Switching to an alternator (w/internal regulator - I used a Nissan P/U truck unit which required minor modification to the cooling fins for lining up with the BE pulleys - see attachment - & a new rear mount off newer Spridget) makes life a lot easier in the long run - electric tach, no voltage drop at idle, compatibility to everything else on the road and a few less components from The Prince of Darkness. I feel that auto-electronics is the one area that has made the greatest of improvements, so why not up-grade? PS: I'm almost certain you DO have to change the coil wires!
 

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You really don't have to change the coil or the gauges when you change polarity. The coil changeover is a 10% change in efficiency at best (so it is a good idea to change but not necessay) but the gauges do NOT need to be changed, they don't care.
An easier way to fix the problem is to just fix the current fuel pump- pull off the back cover and use a point-file (or piece of sandpaper) to clean-up the points and you should be good for another 2 years easily, 5 more likely!
Bill
 
Don't let the guys on the Big Healey forum of this board hear you say that the coil polarity swap isn't necessary. I made that mistake and they came down on me like a ton of something. Swapping the coil terminals is a two second job and supposedly the high-voltage difference is closer to 20%. I won't argue that one way or the other... just pointing out that I got burned as a heretic for questioning it.

I'd never heard the bit about swapping the fuel gauge either. Is it fact of fiction?
 
Fiction, Doug... Sender is a variable resistor. No polarity there.

Only compelling reason I've found for the system polarity switch is for a "modern" radio install.

I feel for ya over the coil thingie. I reverse 'em when doing a conversion, mostly from superstition. /ubbthreads/images/graemlins/jester.gif

The two windings ~are~ different, so I figger it can't hurt. /ubbthreads/images/graemlins/smirk.gif
 
How can it possibley make any difference to the elec which way it goes through a winding, think not. Old wives tail.
 
the coil has two different size windings: primary and secondary. It ain't the "direction" the current flows, but which winding peaks at the higher output at points "collapse."


EDIT: for the record, it doesn't seem to make a whole bunch of difference with a standard coil and points. Dunno about with a fancy whizz-bang coil and eeel-ectronic iggy... That has to be rigged NEG earth anyhow.
 
In another thread, someone mentioned the electronic "pointless" ignition, which I discovered I have on ncbugeye only a couple of days ago when I lifted the ditributor cap for the first time, planning to "check the points".

Is this kind of ignition bilingual wrt earth polarity? Do I need to convert or rewire that when I make the switch?

I do not (yet) have the joy of knowing every inch of my car the way you guys clearly do of yours....
 
The polarity going into the "smart box" will need to be correct. Depending on the unit you've got, it may be possible to just swap ground and power... it depends on whether or not the case is 'ground isolated' IYSWIM. VOM to case and whichever lead goes to ground now (isolated, of course), if you've got continuity it'll mean a different unit. Open circuit and you'll be 'good-to-go' with just switching them.
 
You metioned an "eeel-ectronic iggy" and said it has to be neg-earth, but ncbugeye is currently pos-earth and has one (a Pertronix Ignitor). The PO was thorough enough to hand me down the installation instruction sheet for the Ignitor and it says in item 1:

1. The Ignitor is designed to be used in 12-volt positive ground systems.

Question is, can it be converted to negative earth or do I need to buy a new one or revert to points.
 
Pertronix uses the case as a circuit ground internally, as well as a grounding wire. so I'm kinda sure it'd mean a new box to make the change. They have both neg and pos earth versions. Personally, I'd set up the points and do away with the "Box-o-tricks" entirely. Points last a long time, a spare set is all of $10 and fits inna glovebox... It's all a matter of personal choice, IMO.
 
Hay Doc, I keep looking for this glovebox you keep refering to and the best I can do is an old army 30 mm can. Is that ok?
 
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