I'm doing some distributor work

JetSnake

New member
I want to replace the points in the distributor with a pretronix electronic kit. I'm working on a 74 IH loadstar with a 345, holly distributor part number is 433142c91. Pertronix told me that the part number for there kit is 1481 if the distributor spins count-clockwise, and 1482 for clockwise. It's my dads truck and it's 200 miles away, can someone help me out with this?

Also, is there a better option to get rid of the points? Like maybe a rebuilt electronic distributor?

Let me know if you need more info
 
Huh, clockwise / counterclockwise??? I do not think that sv engines spin two directions (maybe stationary engines do?) are there different distributor drive gears...???

Michael mayben will have to confirm --

if your Holley dist is a points distributor, I believe 1481 is the correct pertronix.

At least that was what was put in my Holley points distributor in the 392 in my t/a according to the invoice.

There is a different pertronix "kit" for IH prestolite distributors -- and possibly for the Holley gold box distributors.
 
Adding to Robert's advice, pertronix has been in the midst of revamping many of the applications of their hall effect trigger systems for converting breaker point distributors. Applications that were previously "adjustable" for setting the air gap initially, have now been revamped to a "fixed" trigger with no adjustment.

I have two 1481 pertronix kits waiting for me in town at the parts distributor for installs to do this weekend. Don't know which version they will be, depends on inventory turnover in the warehouses. Doesn't matter, either one works perfectly.

The magnet wheel design has also changed for some Holley apps, they May now include a small delrin (plastic) spacer as the trigger wheel thickness has been reduced. Problem is...p-tron has not revised/updated their dam instructions for those! So the average diy'r don't know where the spacer goes!

For the record...it goes under the magnet wheel, otherwise, the magnet segment does not align with the hall effect module properly. Then the rotor goes on top just like in the breaker points application.

Same holds true for the four cylinder Holley distributor app which is identical internally except for the point cam lobe count. I did a couple of four banger Holley conversions a week ago, one more in line now.

The old "perlux" instructions for those installations were shit back in 1977, they still are shit today. They try to make this "simple" but because they do not provide accurate detail, it leaves folks who don't know this stuff in the dark and frustrated.

One more piece of advice...over the years, these engines get real messed up by "previous owner virus"! It's entirely possible someone could have swapped in a "early" Holley/IH distributor that looks identical on the outside, but has the "straight point" system inside. Those use an entirely different p-tron application. However, the IH p/n you posted is a correct distributor app for a 345 (curved point) in some medium duty truck applications and is not the governor distributor version. Ya just can't tell what ya got positively without opening it up!

Distributor identification for this IH schnizz May be found in this thread:

http://www.forums.IHPartsAmerica.com/ignition-tech/642-ihc-vehicle-distributor-identification.html
 
huh, clockwise / counterclockwise??? I do not think that sv engines spin two directions (maybe stationary engines do?) are there different distributor drive gears...???

Michael mayben will have to confirm --

if your Holley dist is a points distributor, I believe 1481 is the correct pertronix.

At least that was what was put in my Holley points distributor in the 392 in my t/a according to the invoice.

There is a different pertronix "kit" for IH prestolite distributors -- and possibly for the Holley gold box distributors.

There are "reverse rotation" ihc-produced engines that were used in some industrial applications such as aircraft tugs, forklifts, marine conversions, agricultural products, etc. Not all twin engine marine engine apps were counter-rotating, some manufacturers that used the IH marine conversions achieved counter-rotation of the prop in a twin screw boat by using a reverse rotation marine transmission.

Remember this thread?:

http://www.forums.IHPartsAmerica.com/ignition-tech/1834-distributor-conversion.html

The pertronix unit has been in the marketplace since about 1975, formerly known as a "perlux" unit as that was the name of the company back then, many changes since! And their specialty at that time was industrial engine applications of all kinds, most of which the average truck enthusiast has never heard of or will ever see! Take a stroll through the pertronix catalog and you will receive an education regarding "engines" and distributor applications! Just hope that you never have to screw with an IH motor with a dam lucas distributor!!!

And every IH/Holley distributor has a breaker plate marked with two "holes" for the anchor pin for the vacuum advance arm. One is marked "cw", one is marked "ccw". However, a ccw distributor is actually a mirror image regarding the main body, the vacuum advance unit is mounted on the opposite side.

But...all motor vehicle versions of the ihc-produced motors are "cw" distributor rotation. And don't forget...these motors are gear drive camshafts, not chain drive like most chryfordrolets! The cam gear drives the distributor on these I-4 and sv motors.

The "reverse rotation" engine scenario can be achieved in many ways. Each engine manufacture does it differently, there is no single "best way".
 
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huh, clockwise / counterclockwise??? I do not think that sv engines spin two directions (maybe stationary engines do?) are there different distributor drive gears...???

Michael mayben will have to confirm --

if your Holley dist is a points distributor, I believe 1481 is the correct pertronix.

At least that was what was put in my Holley points distributor in the 392 in my t/a according to the invoice.

There is a different pertronix "kit" for IH prestolite distributors -- and possibly for the Holley gold box distributors.

Marine apps can/do turn both directions. Also the parts on IH motors are not only used on IH apps some are GM and they had both directions. Pertronix detail is generic and applicable to any engine using these distributors.

Come on Robert don't you know the world is not flat. Life exists outside of International crap. :p
 
Moved this thread to the ignition sub-forum for a more appropriate exposure.

Here's a shot of the spec sheet for ihc medium duty truck distributor apps by part number. This is taken from a cts-2301 service manual.

You can see that there is a considerable difference in details for all these distributors that "look the same"! This is why mixing and matching these sparkmakers amongst various sv engine apps usually results in poor performance unless properly matched and set up.

And for the two roberts....robertc ain't had a new ride since he rolled that t'all off the lot back in '73 there in oakland! He and his wife's other ride is a dam corvair they also bought new! You think that boy don't stay confused when he's scruuin' with both a weirdazz IH motor and a dam boxer lawnmower motor out of that fuckhaid ralph nader's legacy????

He May be a berzerkeley wannabe, but he dam shore acts like us normal folks!

Git this...we just got Robert's Binder Bee registration in the mail last week...he registered the dam corvair!!!
 

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  • Medium Duty Distributor Specs.PDF
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Geez, a little slack here...

My somewhat "issue" is that the original poster stated (per pertronix) that a 1481 was for ccw;

Robert stated an IH sv rotates cw.

And, afaik, I have a 1481 in mine...

I was trying to state that IH sv engines in scouts, light line and medium duty only rotate in one direction...

Yes, I know engines in different applications can rotate in either direction -- corvair engines are one --as there is an aftermarket reverse rotation cam so that you can put a corvair engine in vws(bus, ghia, bug, dune buggy) / porsches -- "hooked" to the vw / porsche transaxle... (vw / porsche engines rotate the opposite of the corvair engine.)

corvairs have solid crank / cam gears, also -- though the distributor is driven off a brass drive gear on the crankshaft and the cam gear is aluminum ( a "failure issue").

For the record:

I (we) have two corvairs -- I bought a second 65 corvair in nov 1976 -- as well as the t/a. I (we) have not bought a vehicle since 1976...

My wife bought "her" corvair (new - sort of - a complete repaint / "restoration" in 1976 revealed that the driver's side door and quarter panel were replaced at some point - possibly before she bought it.) in oct 65. We were married in 1968.

I know I am getting senile, but I did not really register a 1973 corvair for the bee? Did I?:crazy: :shocked:
 
Robertc...we're gonna rag yore ass until the bee is done this year!

You will never know what ya registered until ya git here! So I guess that means ya need to bring 'em all???? But make certain the 'vair don't have four speeds reverse and one forward...I had one of those once time!
 
What if you break the little clip that holds the, what is it called, the magnet wheel, down? Can't leave it that way, can I? Will an auto parts store have one?
 
A "clip" that holds the magnet wheel down???? For a Holley points distributor that uses a pertronix 1481 conversion? Never heard of or seen that and I've done a bunch of those installs!

When you remove the rotor, and look down inside the hole underneath which is the component known as the mechanical advance and point cam...you will see a small, round felt lubrication wick. When you take that out there is a "special" locking clip inside that is only used on these distributors and must very carefully be removed and re-installed in order to avoid breakage. Those you will never find except maybe from someone like philbin electric in portland, or.

There is no need to remove that clip to install a p-tron...but if you totally disassemble the distributor advance unit for cleaning, then the clip must come out.

Sorry I have no spares of that clip, in fact I could use a stash of 'em myself.

The magnet wheel in the 1481 kit simply slides down over the point cam and is a "snug" fit. The rotor then retains it in place to keep it from creeping up in operation.
 
Alright, I have my p-tron unit in, but I don't have spark while cranking it over, but I have spark when I let the key off of "start" position and put it in the "on" position until the engine coast to a stop. What is going on, or what am I doing wrong? I had 11 volts at the coil with the key "on" and a hair over 10 volts with the key in the "start" position. We tried running a ground jumper to the coil with no help. We also tried running a jumper to the positive side of the coil from the positive side of the battery, still no help. There is no external resistor with this system.

What do we need to do to get spark while the key is in the "start" position?
 
Even the medium duty, point-ignition trucks have a "bypass"-type ignition primary wiring scheme...same as pickall and Scout 80/Scout 800/Scout II.

Originally the positive terminal on the ignition coil had two wires connected....one wire is used to feed b+ to the coil with the ignition switch in the "start" position.

The other wire which appears to have woven cloth over-wrap is a "resistor wire" (value 1.8 ohms if the entire length is present). The overwrap is fiberglas insulation because that wire gets hot when in use! That wire runs from the "run" side of the ignition switch, through the bulkhead connector on the firewall. That wire is your "ballast resistor", the rig does not use a ceramic ballast resistor as you might be familiar with.

The ignition switch actually momentarily "bridges" the start and run contactors inside the ignition switch momentarily as it springs back from start to run so that the ignition primary current feed is not interrupted.

To install the p-tron, ya simply removed the wire from the points to the coil negative terminal and pulled it out of the distributor. Then ya mounted the p-tron and connected the red lead to the coil positive terminal and the black wire to the coil negative terminal. The other wiring on the coil terminals should not have been disturbed. Also, while cranking (due to voltage drop because the starter is drawing a major amount of juice), the voltage at the coil positive terminal should be nearly the same as voltage measured directly across the battery, open circuit, if cranking voltage drops that low, ya gotta weak battery

check that you have b+ at the coil positive terminal when the engine is cranking over.
 
Thanks for your help, mr. Mayben. I did check the volts at the coil during "start", and came up with about 10 volts. The engine cranked over fine, but then we threw the jumpers on from a running vehicle. The volts May have picked up a little.

Our rig has 2 wires going to the positive side of the coil like you described.

Did I miss something in your last post that I should be trying other then checking for voltage at the coil? It appears that I have voltage at the coil both during "on" and "start". With a "hot" coil, I don't understand why it won't throw spark.

My Dad would feel better if I get his wild rice hauler running. I tell ya, those loadstars can haul a load!!!
 
Rice hauler??? Let's git on it!

Here's a scan of a 1600 series and higher loadstar schematic. This is not the full package, only the basics that are under the hood! Since it's a .pdf, you can enlarge it and then print the magnified section if need be. This scan is pretty sharp compared to many of the pages inna cts-2300!

Look at circuits that are numbered "16" at the ignition coil and trace those out on your rig.

The 16b wire run is either black or green on the positive coil terminal, it carries the b+ signal from the starter solenoid terminal to the coil for "start". This should be the circuit you are having issues with since it won't fire in "start".

The 16 wire run is the "resistor wire", note the "note" in the right hand column for the value of that wire run. That wire runs through the bulkhead connector from the ignition switch "run" terminal.

Disconnect both wires at the coil positive terminal. Place your voltage meter probe on that wire terminal, and the other probe to ground. When you crank the motor over continuously, that reading must be the same as b+ or within a fe tenths of a volt.

With the key switch just in the "on" position and the 16 wire disconnected, between that wire and ground you should see about 3 volts less than b+ that ya saw on the other lead, that is the because the resistor wire is a "resistor" and will reduce the voltage to the p-tron and the coil when the engine is running.

If ya don't have b+ at the "start" wire to the coil when cranking, then figgr out why!! Look at all wiring connections, especially the bulkhead connector!

I'll be back inna few hours!

Ps...did that version of the p-tron 1481 include the small piece of acrylic "feeler gauge" (0.030") for setting the magnet wheel to module air gap??? If it's the latest production unit, the air gap May not be "adjustable. If it is adjustable, then make sure ya set it to 0.030".
 

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  • 1600 Up Basic Wiring.PDF
    2.9 MB · Views: 640
Ok, we'll check this out.

The unit I have is adjustable. The black plastic piece is used for setting the air gap, right? What is the white plastic washer like piece for and where does it go?

The engine had spark during "start" mode with the points in. I can't see why it won't work with the p-tron unit unless it's the p-tron unit its self, I don't know.
 
ok, we'll check this out.

The unit I have is adjustable. The black plastic piece is used for setting the air gap, right? What is the white plastic washer like piece for and where does it go?

The engine had spark during "start" mode with the points in. I can't see why it won't work with the p-tron unit unless it's the p-tron unit its self, I don't know.

The thin plastic "feeler" gauge supplied in the past has been clear! And if you have a plastic "washer", then it goes under the magnet ring, not on top. That brings the magnet ring "up" into proper alignment with the centerline of the p-tron hall effect module.

Those p-tron instructions suk don't they?? Very lacking in info and have not been revised to reflect the newest changes.

Can you post a pic of the p-tron kit components? The 1481 May have been re-designed along with the other stuff I've discovered in the last month! I have a 1481 on order now but won't be here until Tuesday, when I see it I can determine if p-tron has also redesigned the 1481 like some of the other numbers.

The gold box wiring system is completely different! No "resistor" wire is used for those. I have posted about that in other threads here in the ignition sub-forum just recently, including an oem schematic.
 
I can send a pic, but it's going to have to be until I get back to my place. We put the points back in it and it fired right up! After wards, I got thinking, we didn't use the little jumper wire inside the distributor when we used the p-tron unit. Could this be our problem.

We put a different set of head on this 345. I have more questions on this topic later.
 
These are the heads we took off, 359489-c3. These are the heads we put on, 432089-c1. The heads we put on don't look like they have as much compression, and we used a thicker head gasket. When we pulled the new heads of the donor engine, we noticed the thinner steel head gasket. How much is this going to hurt our compression ratio?
 
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