M135 M211 distributor interchange replacement and electronic ignition conversion

[DUUANE]

Hi everyone USMC 00-08 has asked me to start a thread as repository for information regarding the replacement of the stock 302 gmc military distributor with a civillian unit as some parts for the military are no longer in production.
I will try and cover distributor interchange. I have read that other members have used a distributor from a chevrolet 235 six with success. There was a change in the style of hold down clamp but i will have to investigate further. I have one in a 57 chev school bus chassis and another in a 54 chev 3/4 ton so we can see if there is a difference between light and medium duty units.
I will assemble some manufacturers and part numbers for under the cap electronic ignition conversions. I used this on my 55 Dodge M37. I built the truck from a bare chassis and couldnt find a military engine but was lucky to find a good civilluan 251 so thats what i went with.
Ther electronic conversion was the best 50 bux i ever spent. Easy fast starting, more power, and more range. Never had to mess with a set of points again in the bush. Pure joy.
The only downside is they are a little sensitive to high voltage..so if your voltage regulator packs it in and your're on the highway at 3000 rpm making 20v (in a 12v system) it will zap the transistor in it and youll have to replace it.
The conversion replaces the breaker points plate in the distributor (not all the kits are like this but the one i like best does..read on.) And has a magnet setup that presses onto the distributor shaft and lives under the rotor. Its a hall effect switch and flying magnet setup. The other style is an infra red led, a photo cell and a plastic disc with slots molded i to it to allow the led and photo cell to alternatly "see" and "not see" each other. I wasnt really impressed with the quallity and accuracy of the molded shutter wheel. So i went with the hall effect unit.
Because it replace the whole breaker point base plate i was able to rebuild it, gap the points, and drop it in a ziploc bag with a pouch of sillica gel and toss it in the glove box as a saftey i could change out on the side of the road should my voltage regulator pack it in and quit.
I will also try and assemble information from other sites on modifying a later model GM HEI distributor for installation as an assembly.

 

[DUUANE]

Info on converting mopar electronic ignition

Ok lets try again..
Go out and find a 74-84 or so GM car or truck rob the distributor..
Remove the cap and rotor.
Under the rotor will be a back or possibly a white module held down with two 1/4" screws and has 2 wire connectors..this is the part you want. Remove it.

Cut a piece if 1/4" thick aluminum big enough to mount the module and with enough meat to drill 4 holes to mount it to your firewall/inner fender..this is your heat sink.

Go to your local computer store and get a $3 tube of ceramic heat transfer paste.
I use.
https://m.ncix.com/products/sku/79330/?promo_id=1382

While youre out grab some 6-32x1.25" screws nuts and lock washers to mount the module to the heat sink. You need 2 of each. Find four 1.5-2" or so bolts, 12 nuts and 8 lock washers (internal lock washers are best Vs. The standard split washer for this)

Go back to the shop. Center your module on the heat sink and mark the 2 mountin holes with a finnishing nail or something that fits in the holes. Center punch the 4 holes for the bolts to mount it to the firewall/inner fender. Drill appropriately sized holes.

Take the heat sink over tk the truck and try and pick a spot in the engine bay that is protected from mud splash and road spray but has clearance to wiring harnesses fuel lines or things that may not like heat and melt/catch fire..this is a heat sink..it runs hot enough u der continuous operation to remove your thumb print if you touch it at the wrong time (ask me how i know) and its a good idea to check the inside of the firewall too if youre going to mount it up there.

Mark the firewall/inner fender..drill holes.

Get your thermal transfer paste..apply enough to coat the back side of the module but dont go crazy..its almost impossible to wash off and its like ceramic anti sieze..once you get it on you..its on everything..wear gloves..dont rub it in your eyes..

Mount the module to the heat sink.i use some dielectric grease under the head of the screws and nuts..they ground the module to the heat sink. I also sand a little paint around the mounting holes in the firewall/inner fender and use dielectric grease for a solid body ground for the heat sink.
Mount the module/heat sink to the truck. Double nut the heat sink on the mounting bolts to create an air gap between it and the firewall/inner fender.

Now measure for your jumper harness.
You have 2 choices.
1. A permanent installation that eliminates the factory plugs.
2. A bullet connector jumper harness that allows you to easily return it to stock.

I usually like to remove the magic box and mount the new module in its place. This allows me to use the stock power supply harness convienently and have as short splices/jumpers as are practical.
The distributor signal harness i like to overlay with new wire. The reason is that the signal from the reluctor inside the distributor is weak and sensitive to high resistance..one bad connection or cheesy wire and you have no spark. There is usually a 2 prong connector right at the distributor..i break in there.

The modules (if youre buying them new. They are cheap, but if you can have them tested in store..i have had a couple that were junk out of the box. They were chineeseium not the gm modules..and most stores have a no return policy on electrical parts so due dilligence here.)
..modules come in 4, 5 and 7 pin varieties. The one we want is a 4 pin heavy duty unit.
The application i use is 1980 chev c/k 20 with 454.

One pin on the module is smaller than the others..you will need a smaller connector for it..
The others you can use the standard cheapo harbour freight/princess auto crimp kit connectors. I like to modify them. I take a hacksaw blade and cut it to a comfortable length..4 or 5" then use it to cut and remove the plastic collar on the connectors so i can crimp, solder, and get a nice tight heat shrink protection over it.
Make your harness..use dielectric grease on the connectors and wrap the bullet/jumper connection with self vulcanizing tape NOT regular electrical tape..test your work..if its all hooked up right you should have joy.
Add some plasic loom and secure with zap straps and you should be done..for a long time.

You can use this module to run off points but there is another circuit to build and add in series.
The way i understand it a points system opens the circuit to de energize the primary circuit in the coil to fire the plug.
An electronic distributor sends a small induced AC current that signals a transistor to open a circut in the primary (the module) to fire the plug. So when you try to trigger a module with a points distributor the circuit ends up being kind of backwards..energized until the points open Vs. Energized AT the moment the points open. Hence the extra circuit required to operate the module in this scenario..
I will find the extra circuit schematic and add it asap.

I try and edit this again for simplicity and to add any extra info people need.

 

[CMPPhil]

Hi Duuane

You mention distributor as being the same as civilian chevy 235, which 235 the early or late as I'm not sure they are
interchangeable. Will do some digging the Chevy parts book and see what info I can dig up.

Good idea to gather up key bits of info on parts.

Cheers Phil

 

[DUUANE]

Hi Phil..the post i read said he used a 235 but had to change the hold down clamp from bolt down to band clamp i think it was..said the distributor was available from autozone so im going to guess it was a late one..there was a part number too ill try and find the thread/ part number.
Im not quite ready to pull my military distributor but when i am ill take some pics and measurements and post them up.

 

[DUUANE]

Here is the thread ..post #6

https://www.steelsoldiers.com/showthread.php?60039-GM-302-Distributor

 

[DUUANE]

Hei retrofit for point distributor.

I love this modern age of internet and information. Here is a good write up and several schematics for using a point style distributor to trigger a GM HEI 4 pin module. The advantage is that the module switches the high amperage primary coil load instead of the points..allowing the points to last and last and last..the only issue will be humidity/condensation corrosion. Especially if it sits for years at a time.
Enjoy.

 

[DUUANE]

Here is the under the cap conversion kit i used in my M37 because i had a civvy distributor i ended up doing a hybrid 12v charging/running/lighting-24v starting starting as the military clutch/flywheel/ring gear were different and i had to retain them. So had to also keep the 24v starter. Or order a $500 WC WWll replacement 12v starter.
I had no wiring harness so i had to scratch build anyway so i used what i had.
I will search for 24v options for us.

http://www.hot-spark.com/1-Hot-Spark-Industrial-Engine-Electronic-Ignition.htm

Edit; no 24 volt from these guys

 

[DUUANE]

These guys make a similar hall effect setup in 24 volt. I've emailed them to see if they have a kit for the 235 chevy distributor.

http://www.simonbbc.com/

Edit: no 24 volt from these guys

 

[DUUANE]

This is awesome..i wish i could shake this guys hand for the write up. Its 12 volts but does what we need. For the cost involved its worth adding a circuit to run it.

http://devestechnet.com/Home/HEIgnition

 

[CMPPhil]

Hi Duuane

Interesting reading, will have to print out some of the pages and then go compare with details on my late 50s 235 and 62 261 chevy engines in two of my CMPs. I have posted the engine section of the 1960 Chevrolet Truck Manual if that is interest http://canadianmilitarypattern.com/1960 235-261 Engine Manual.htm

Cheers Phil

 

[DUUANE]

Thanks Phil. I have the 1961 supplement but not the 1960 manual.. after looking through your link i think i may have a 261 in my bus chassis..it has the full flow oil filter that hangs off the manifold. I will have to look closer at it and see.

 

[DUUANE]

Distributor donor..possibly

Here are some pics of the first donor civillian setup. Its in a 1957 chevy school bus chassis..could be 235 or 261..im not sure at this point.im posting up the numbers, maybe CMP Phil will have the data..i will look in my old block and head guide as well.
This distributor has a bolt down deal so hopefully it may slide right in.

Ok on to the pics..

 

[USMC 00-08]

Is there a part number for those Autolite plugs? Maybe we could find a worthy substitute. I know it is possible to find replacements for the M151 style plug, hopefully we can for the M211 series.

Mine had an ignition problem too. Discovered that it was the isolator right as the wire goes into the distributor. Had to tear it apart and soldier the wire back together. I was considering switching to an all electronic ignition. I found an ad that says M-series rebuild offers one. Has anyone tried this before? www.mseriesrebuild.com

I am trying to move this over here so we have all the info in one place.

I believe the Autolite number is 2245. There are some civilian equivalents. A spark plug wire adapter that would let us use civilian wires on the military distributor would be a fix that could get a lot of us by for a long time, but I'm not sure such a thing exists or know how to make one. It is a good idea in my opinion to plan for the future on this distributor topic.


Here is a thread that has a Pertronix conversion that I thought was interesting.

https://www.steelsoldiers.com/showthread.php?22682-Pertronix-Conversion

 

[DUUANE]

I remember seeing a diagram somewhere that the military sparkplugs were serviceable..as in they could be dissassembled. If that is the case, as long as your porcelin's are ok the sky is the limit. Just cant remember if it was a military plug or an old flathead ford plug..i will dig. Loctite makes some pretty high tec stuff these days..maybe there is something with enough dielectric strength to allow fabrication of an adapter for the distributor so we can use civvy wires...more digging

 

[DUUANE]

Maybe someone could post the delco/remy number for our 135/211 djstributors. The tag off my 235 is gone ill check into the '54's distributor number.chevy 3800 2wd 3/4 ton. 235 six
If phil could post his numbers for comparison/addition to the pile 216/early 235..my stuff is mostly late.

 

[DUUANE]

I found this on a .pdf downloaded from the pertronix website.

1941-53 6 216, 235, 261 cid engine 36, 55, 56, 57 Delco 1167
1954-62 6 216, 235, 261 cid engine 36, 55, 56, 57 Delco 1168

36,55,56,57 are footnotes.. 1167 and 1168 are the ignitor kit numbers..
1167 would be non vac adv.
1168 would be with vac adv i would immagine based on the application years.

Here are some delco/remy distributor part numbers i scanned from the web application was 1963 byscane w 235.
The same website lists the same part numbers for the 248 and 270 GMC engines
248 and 270 application was 1960 truck

1112388, 1112389, 1112392, 1112396, 1112400, 1112403, 1112407, 1112411, 1112414

Based on the info from the link USMC 00-08 posted i would think the 216/235/261,248/270/civvy 302 use the same distributor, r6602 and 302 gmc distributors use the same breaker plate..all we need now is verification that the distributors will physically interchange...edit..i feel 99% certain this will interchange

 

[DUUANE]

Just found this..its for the M715 autolite distributor and 24 volt..so we have a winner i think.

PerTronix MV-161A Ignitor Autolite 6 cyl 24 Volt Negative Ground
The number on the hall switch is 09AD-24VN so we will need to order the 1167 or 1168 with this part.

 

[CMPPhil]

Here are some pics of the first donor civillian setup. Its in a 1957 chevy school bus chassis..could be 235 or 261..im not sure at this point.im posting up the numbers, maybe CMP Phil will have the data..i will look in my old block and head guide as well.
This distributor has a bolt down deal so hopefully it may slide right in.

Ok on to the pics..

Hi Duuane

Now you got me scratchin my head, started searching for your engine casting number 8769716 in the casting listing no surprise it doesn't showup, but this is not uncommon most of the databases are looking at US numbers and don't show the Canadian casting numbers. So that will take some digging back through the information on MLU.
The big tip off between truck 261 and truck or car 235, is the oil lines on the 261 truck are huge. Will dig out photos.
CAUTION all truck 261s are full flow oil filter, operating the engine with those lines plug results in death of the engine in guick order.
Will see if I have good photos of 216, 235 and 261 distributors.
Still digging through US and Canadian parts book to see how many different distributors bodies.

Cheers Phil

 

[DUUANE]

Hi Phil..i havnt had time to crack open my block and head guide yet but i remember reading that the 261 blocks only came in truck applications and as such never had the cast in mount bosses on the side of the block..where i read it and how reliable that is i dont know..but my block has the bosses. The numbers will tell i immagine. In any case this engine runs smooth. Too bad my CMP is a ford or i'd have a use for it.

 

[CMPPhil]

Hi

If miss read the casting number and is 3769716 then it comes up as 235 truck 58 to 62.

Have not gotten to other computer yet to search for photos.

The Canadian Pontiac I've been told had a 261

Cheers Phil