'77 point dizzy to Electronic Ignition dizzy questions

[daretzcouple]

Ever since i bought my 77 620 I have been going over it slowly, replacing vacuum hoses and fuel hoses that were tired and long due for replacement. I have since started on the electrical side, new wires, a new starter( mine wasn't turning over until the third or fourth key cycle) This inevitably brought me to the distributor and what would be the best course of action to make it reliable for a daily and I have came to the oh so important debate of weather i keep the stock point style distributor that is known for wearing out and having to be replaced/ adjusted or swap to a fancy EI distributor and if i went that way I decided would be the matchbox style.

 

So my questions to the datsun gurus out there (datzenmike looking at you) what drop in distributor can i put in my 77 L20b would be the easiest for this to happen? Would this work? I know i would need the rotor and I could use the cap from my old one

https://www.ebay.com/itm/113498800247?ul_noapp=true

 

 

Now the second part, I already bought a new coil, a ngk that is stamped "12 volt, for electric ignition only" I can get rid of all of this crap right? I assume this is the ballast used by the old coil/ points 

 

 

PS. when i pulled the cap off my stock distributor part of the rotor is missing, I believe the point gap is too tight. Basically its time for an upgrade. Thank you to everybody that can help me out here!

[datzenmike]

Well the points distributor doesn't wear out any faster than an EI but... the points (and condenser) do wear out from arcing and need replacing every 12-15K but wiser to change every 10K They can be filed down and gaped every 5K. If you do this they are quite reliable.

 

However if you want to eliminate this bother, an EI distributor gets rid of this replacement, gaping, filing, lubricating and maintenance altogether. You can continue to run your stock coil if you keep the dropping or ballast resistor but then you keep the same spark performance and only loose the points. The EI distributor is solid state, has no moving parts that wear and can handle increased current loads that would burn a set of points out in under a hundred miles. Because of this, a special 12 volt coil is used without a ballast that produces a higher voltage spark.

 

If getting an EI distributor just remember that electricity ALWAYS searches for the quickest easiest path to ground to avoid doing any work. If your wires are in bad shape or the cap or rotor cracked or carbon tracked or plugs dirty on the outside the spark will be glad to take a short cut.

 

All L20B points and EI distributor caps are the same size.

 

One side of the ballast will have two wires to it. One has power with the ignition in the ON position and the other has power in the START position. Join them together and wire the EI distributor up this way...

 

 

Save the old distributor, (never throw shit away, give away if you have to) this way if you sell your truck you can put back and keep the EI for your next L20B.

 

This is an A series matchbox list. It won't fit your L20B as it is.

 

 

The '78 L20Bs ised a different EI system with the 'matchbox' about the size of two packs of playing cards and mounting it under the dash in the cab. Aptly named the 'Remote Igniter' it worked the same. If you should find one it's probably been separated from it's box. No worries a $10 HEI unit from a GM distributor can easily be wired in to replace the 'module' This also works on the Matchbox module if it fails.

 

 

 

The 1.6 ohm coil is wrong, should be from a '78-'79 620.

 

[daretzcouple]

Thanks for the reply mike, it makes a lot of sense. I already have the 12v coil, so i will bypass the ballast completely. 

 

 

This is the type I would need then correct? If so this is the one where the GM HEI comes into play correct?

https://www.jcwhitney.com/details/A1_Cardone/Distributor/A131620.html?TID=gglpla&origin=pla&gclid=Cj0KCQiAp7DiBRDdARIsABIMfoCONF_U_g0FvfEvdmGixHfZeEPmOGWkD--VeoBYaZcwlW8VYZvbJboaAl72EALw_wcB&gclsrc=aw.ds

[datzenmike]

This one...

 

 

... is the '78 remote igniter distributor that you can substitute an HEI module to. And make sure the coil dose no say it needs an external ballast...

[daretzcouple]

so the second link i showed is indeed the correct one? Don't mean to frustrate you, just making sure I am getting the right one before I throw $100 and get the wrong one

[banzai510(hainz)]

hope YOUR the timming plate matches the mount. so youll be in time. But I believe the point plate and 1st gen EI are the same

 

the starter clicking 3 4 times ifs most likely a worn selinoid or key switch is getting old. One can add a hot start relay.

TSI Automotive sell New Denso Gear reduction L series starters also for 200. the Autozone and O rileys are not that great

Edited January 28, 2019 by banzai510(hainz)

[datzenmike]

Yes, either the ignition switch is worn out, the solenoid or too large a voltage drop on the start wire. Like Hainz says, look up 'hot start relay'.

 

 

Yes that distributor is the remote igniter style that you can substitute an HEI module for.

[G-Duax]

I've been through several Datsuns that sooner or later the ignition switch 'wears out', but have never replaced one yet.

When they start to become a problem, it's because the contacts won't carry the solenoid current any longer.
Like banzia510 mentioned, adding a simple relay between the switch, and the starter solenoid works quite well.

The only current that the ignition has to handle is to activate the relay, which then carries the higher current.

[daretzcouple]

8 hours ago, banzai510(hainz) said:

hope YOUR the timming plate matches the mount. so youll be in time. But I believe the point plate and 1st gen EI are the same

 

the starter clicking 3 4 times ifs most likely a worn selinoid or key switch is getting old. One can add a hot start relay.

TSI Automotive sell New Denso Gear reduction L series starters also for 200. the Autozone and O rileys are not that great

 

 

So so now your saying the timing plates might not be the same if I was to swap to that EI distributor? 

 

Also so I already picked up a new denso starter online. As well as replacing the positive terminal to starter. 

 

@datzenmike so that’s the style to go with? I did see oriely/ autozone do carry the 79 year with the matchbox style on the side. Would that be smarter to go with?

[datzenmike]

Up to you. The matchbox is probably more that the remote igniter but you still have to get and wire an HEI module to it.

 

 

The 'timing adjustment' plate is not that critical. As long as you have spark you can drop the oil pump and clock the distributor under the #1 wire and then time it properly.

[daretzcouple]

On 1/28/2019 at 7:57 PM, datzenmike said:

Up to you. The matchbox is probably more that the remote igniter but you still have to get and wire an HEI module to it.

 

 

The 'timing adjustment' plate is not that critical. As long as you have spark you can drop the oil pump and clock the distributor under the #1 wire and then time it properly.

 

 

Okay cool. I think I’m going to spend the little more and get a remanufactured 79 distributor with the matchbox. As long as I line the new one up on the engine like the old one was I shouldn’t have to mess with timing at all right? That’s what I’m thinking. 

[datzenmike]

Expect to re-time it. It will be set for the engine it came off of. Also there are multiple base plates used on them. It can definitely work.

[daretzcouple]

11 hours ago, datzenmike said:

Expect to re-time it. It will be set for the engine it came off of. Also there are multiple base plates used on them. It can definitely work.

I appreciate it datzenmike. I think I have all the info to make the leap onto EI. You have been a big help

[Pacific coast Datsun]

I did a write-up a few years ago covering this topic.

Search "lose the points go electronic"

I did the EI swap on my 620 & took pics & posted parts #'s.

It's an easy mod & should only take a few hours.

[datzenmike]

With increased voltage available, you could experiment with opening your plug gap to 0.038 to 0.042"... or less. A wider gap produces a longer spark, analogous to lighting a camp fire with a bigger match. However the wider gap will force the EI to a higher voltage, specially under load, and if your wires, cap and rotor are not up to the task it will seek out an easier path to ground than the spark plug. I keep my ignition system in good shape, clean and dry and use dielectric grease on all the nipples and plug connections. 

[daretzcouple]

So just wondering. If I take off the old distributor and set the new one like old and drop it in, I should in theory, not have to mess with timing at all. Right? 

[datzenmike]

Maybe. Not necessarily. You are not replacing it with an exact copy. I would still want to know if the timing is correct for best running power and mileage.

[daretzcouple]

Very true. Only reason I asked was because since I have A/c the number 1 spark plug hole is blocked making the whole checking for tdc harder than it should be. 

[datzenmike]

Use flash light and look through the oil fill cap to confirm both #1 cam lobes are pointing upwards or remove valve cover OR turn engine till rotor is pointing near the #1 spark plug wire on distributor cap... when look for timing notch on pulley and set it to  (zero) on the timing scale on the timing cover. TDC.

[banzai510(hainz)]

I would take photo of the dist rotor pointing where it is and install the new one and esee where it points/ if close then you just adjust the bolt on the hold down plate using a timming light

[daretzcouple]

I feel like I am just over complicating everything to be honest

[datzenmike]

It may be close enough to re-time and go just as it is...... If out farther than adjustment can bring into time, you can drop the oil pump and adjust the drive spindle it shares with the distributor. This will place your distributor into the adjustment range. 

[Pacific coast Datsun]

Please watch the Hainz L series video on You tube. It explains SO MUCH ! L series motors are very basic to set up & maintain. Take your time...view / read as much as you can & you'll be back on the road in no time.