question for, Electronic Ignition upgrade

[Izzy]

Hi Ratsun community,

 

I have tried to research in the forums but could not find anything , at least not to for my query.

 

I have a Datsun 521 truck, well it did not pass emissions test, the previous owner put a weber carb and look it is delivering to much gas for what the spark plug can manage,

 

I was told that upgrading to an electronic ignition setup will help to burn the extra gas, without modifying the carb,

 

the distribuitor I have has a dual points distribuitor, my truck is 1971,

 

I found in the forum that pertronix is more for a single point distribuitor than dual set,

 

does any of you can point me to a match for my distribuitor?  or is loking a distruibitor replacement a better option?

 

does any of you know or is selling one in good working conditions?

 

I like to work on my truck but I'm bery dummy when looking into parts numbers and matches for swapping things around,

 

thanks

Israel.

 

 

 

[datzenmike]

There is only so much oxygen in air and it can only combine with so much fuel when burned, so no matter how much you try to burn it there will always be some gas left over.

 

Better, cheaper and easier to adjust the mixture screws or at worst re-jet it. Read this... http://www.carburetion.com/Weber/adjust.htm

 

 

 

and welcome to ratsun Izzy.

[bananahamuck]

You have to change the distributor to a single point one,,, and on certain models(of the single point distributors) machine down the ring at the top so magnetic sleeve can slide down shaft... I had one done the machinist charged about $20. bucks.

[dr.feltersnatch]

Agreed with datzen mike, more spark even if it did help (I dont think it will) is just a band aid on the problem. Fix your rich mixture and enjoy more power and better mileage

[dr.feltersnatch]

And if you still want to upgrade to electronic ignition search for matchbox.

[Izzy]

Thanks guys, I will try to work the carb settings first.,  

 

I will follow-up this post.

 

thanks again.

[DanielC]

There are several ways to not pass an emissions test.  What specifically was wrong?  How do they test?

 

If the CO is too high, that indicates too much gas, in relationship to the amount of oxygen available  It cannot burn all the gas.  it burns all the gas it can, so the spark worked, and started the fire.  That is not an ignition problem.

 

if there is too little gas, in relationship to the oxygen available, you can have a lean misfire.  The mixture simply will not burn.  A stronger spark may help it burn, but usually not.

 

Or the spark could simply be weak, or the spark plugs dirty.

 

if you can, tell us specifically what failed your truck.  

By the way, I have had Datsun 521 trucks, since the early 1970's.  we also have had emission testing in Oregon since about 1975, although now they do not check older vehicles any more.

 

I also have this manual.

[datson4life]

Where are u that ur 521 requires emissions test?

[Izzy]

Daniel and Datson4life,

 

I moved to Utah, and had to do the emissions as my sticker was about to expire, before I was on Texas, finding that here i had to do this., :(

 

CO is high while Idle , but ok on high rpms,

 

 

my truck is 1971 so is not exempt, :( 

 

 

The following vehicles are exempt from Utah emissions inspections:

• New vehicles with Manufacturer’s States of Origin (MSOs).
• Vehicles under 2 years old.
• Vehicles model year 1967 and older ONLY in Davis, Salt Lake, Utah, and Weber.
• Vehicles model year 1968 and older ONLY in Cache.
• Motorcycles.

[datson4life]

All bad, on the plus side u dont have an expensive catalytic converter to put up with, and a thousand smog hoses compared to new cars, like mentioned above with the right mixture i dont see why it would fail

[DanielC]

A quick way to adjust the idle mixture, to meet emissions.  You need a tachometer that will show low RPMs, and a vacuum gauge.

The kind of tachometer you want is a dwell-tach.  The vacuum gauge is usually also a low pressure fuel gauge, and both should be available at an auto parts store.

 

You should also adjust the valve clearance, set the dwell (point gap) on the points, and set the timing.  Get the engine fully warmed up.

There should be a small hose fitting on the number three, and four intake runner on the intake manifold,  That is where you connect the vacuum gauge.  The Dwell tach usually gets hooked up to coil minus, and ground.   Set idle speed to 750 RPM, with the idle speed screw.  This is the one that moves the throttle stop.   Adjust the idle mixture screw for highest speed, and vacuum.  If the idle speed goes above 750, adjust the idle speed screw back down, and then adjust the idle mixture screw some more.  Adjusting the idle mixture screw out makes the mixture go rich, and in makes it go lean.  The idle speed screw, and idle mixture screw do interact with each other.

 

Once you have the best idle, shown by the highest vacuum at 750 RPM, use the idle MIXTURE screw lower the idle speed  to about 700 RPM.  Yes, I said use the idle mixture to lower the RPM.   Then have the engine emission checked.  

 

This is the method for adjusting the stock Hitachi carb.  You have a Weber carb.  It may require more or less "idle RPM drop" to get the mixture good out the tailpipe.

 

Remember, if it checks too rich at idle, turn the idle mixture screw in.  Too rich makes the CO go up.  It you get to lean, you can cause the lean misfire.  this shows up at the tailpipe by high HC, that is unburnt gas.  If high HC, turn the idle mixture screw out a bit. to richen the idle mixture.

[DanielC]

Now back to your original question.  If you want to upgrade the ignition system, get a Matchbox distributor, and its coil.  I would not mess around with a Pertronix system.  The Datsun matchbox is much better.  Do not buy any fancy aftermarket coils even if they are in a pretty finned case, and painted yellow.  the OEM Datsun (Nissan) coil is a higher quality one.

[Izzy]

Daniel , thanks starting to work on the settings, I have the right to a re-test after failing, so will take few hours to try to tune this thing, I have not problems driving, trucks drives fine, if that doesn;t work may have to try something else.

[bananahamuck]

I wouldn't say a Pertronix is some "fancy"  get up that doesn't work... :rofl:

   . Don't let these guys bullshit you...  GOOD working matchbox distributors are pretty dang expensive these days..  More than twice the price of buying a single point distributor AND buying Pertronix unit, ( if you even find a good matchbox that is) ...   i have a 3 sets of pertronix ,,one set has been in my 55 for at least 10 years,, one set in my brothers 510 for at least 7 years and the set in mine just under 2 years..   And you use stock coil that came with truck.

 

 

Just my opinion.

[datzenmike]

Pertronix is ok, but only replaces the problematic points. The EI matchbox also has much higher output voltage..

[dr.feltersnatch]

you should be able to find a matchbox for about $100 or so. maybe a few bucks less if your willing to wait for a deal.

[uberkevin]

Can't you still buy them on rockauto?

[banzai510(hainz)]

yes but you need the correct mount as he would have a L16 distributor mount

[dat521gatherer]

Here is my old thread when I hooked up my 521 electronic ignition. Might have some useful info for you for the wiring and pedastals.

http://community.ratsun.net/topic/5143-dizzy-plate-help-needed/page-2

[Izzy]

Guys, thanks for all advice, those were of great help, 

 

I worked on the weekend with the truck and nuned as best as possible, and it did pass, just below the limits, ..! :)

 

 

thanks again,

 

this forum is very valuable

[dat521gatherer]

Great job.

[Zonargx]

What Pertronix part number do I need for my 521 single point distributor?

[yenpit]

First thought was "Look it up!", but I see Pertronix doesn't list much Datsun!  I have a part #1741, so maybe research a little more to make sure that's it!  Apparently it is Datsun 4cyl with SINGLE points (not dual!), so hope that's the correct part # for YOU!

[mainer311]

Yes, that’s the right one for single points. I run that kit in my roadster.

[Zonargx]

Thanks I’ve been seeing a lot of that part number #1741 when I type my model. Am I missing the regulator or is it normal for my truck to not have one and also what is this green and yellow wire next to the distributor?