M135 miss firing engine

[rustystud]

Normally I don't comment on Engine problems, especially on gasoline engines, but I had an issue recently that might help out others here.
I was diagnosing an engine miss that I just couldn't find the cause.
After pulling the Distributor and tearing it down I found the culprit. The distributor cap had an extremely high resistance on this hole. You can see the discoloration in the photo.

I knew from Tech school back when I was an apprentice that several manufactures of distributor caps will put resistors inline in the cap itself. So, after sandblasting the cap I went after the plugs in the bottom of the holes to see what I could find out.

If you look closely, you can see rust and corrosion in the one hole. The other holes look fine.
Inside these holes are a small spring, a piece of metal rod and a small round sealing cap. The cap is what you normally see when looking down the holes.
You can see the one cap that is rusted . That was the bad hole.
Since these caps are becoming hard to find many people are just cleaning and reusing them. This will I'm sure become a major problem as time goes on.
So, if you have a mysterious engine miss that you cannot seem to find, then checkout that cap for signs of overheating due to high resistance.

 

[Bulldogger]

Interesting. I have seen arced and carboned-up distributor contacts before, but rust is new.

I realize it is not MilSpec, but are there modern retrofit HEI ignitions or other contact-less electronic options for the M135 engine? They may not be water fording capable, but anything I get with points anymore gets an upgrade if I can find a compatible electronic option of decent quality. Good points and good capacitors/condensers for classic ignition distributors haven't been made in decades, at least that I have seen. I am SICK of someone advertising super-duper points only to find some kind of adapted Blue Streak set, as they used to be called. The tiny contacts and unserviceable parts were a money-draining PITA, so I started finding ways to adapt electronic options.

I'm sure a purist or two will flame me, but I can't stand points systems anymore, not because of their design, but because they are no longer available in the quality needed. Most of the time when I found NOS, they were rusted and no longer in good condition and condensers were aged out as well. Well-made points and recent-manufacture condensers, sure I put a lot of miles on those, but I can't get them anymore.

I had a '56 Triumph Tiger T100 with the magneto and points. There were ZERO modern points options at the time. The manufacturer's service steps for those points consisted of filing or sanding to set the contact surface geometry (flat across the entire contact surface) and then hand polishing the two surfaces to mirror finish (or they would carbon up too fast). No one is building points with enough meat on the contact surfaces to be filed and mirror-polished these days!

BDGR

 

[rustystud]

Totally with agree with you Bulldogger about switching to a newer HEI type of ignition. The problem lies with the small market share these military engines present. Yes, there are comparable Civilian engines, but they too represent an extremely small market. So basically, were stuck with the stock points type of ignition. Now there where point type to electronic conversions made, ( I believe their name was Pentronix) my buddy converted his Corvair collection to them years ago. I'm not sure if there made anymore though. Again the problem with our Military engines is will the civilian distributor adapt to it. I don't know. There is also no way you could easily convert the Military distributor to any aftermarket conversion kit. The whole "distributor cap" inside the "sealed unit" thing really throughs a monkey wrench into it.
So in the end we are stuck with this distributor which at one time was "state of the art" and now is so obsolete it's crazy.

 

[msgjd]

well that explains some things ! .. i did not know such items were buried in caps ...

i've had a few errant caps the last 50 or so years that passed the "nightfire" test (no arcing seen in darkness) but they still missed after a good cleaning and with new or freshly-serviced other ignition parts .. I had to resolve to tossing them without any answer as to their failure .. now i know ! thanks for the info

 

[msgjd]

The tiny contacts and unserviceable parts were a money-draining PITA, so I started finding ways to adapt electronic options.---------I'm sure a purist or two will flame me, but I can't stand points systems anymore, not because of their design, but because they are no longer available in the quality needed.

BDGR

I have no issue with people swapping out for electronics, it's their rig.. However i would have to be dragged right down to a last resort .. I sure agree with you about the lack of points quality nowadays, they are crap .. It's pretty disgusting when "worn-out" 60 or 70-year-old points have more meat on the contacts than a brand new set made of chineseium, not enough meat on them to be worth the time/effort to install..

I only file when i absolutely have to .. Otherwise my US or German-made points get a machinist cloth treatment depending on how much i run them.. Over a dozen operational, all have points manufactured prior the 1990's .. Just think about how many points we threw away over the decades "just because" it was habit to change them out every year instead of cleaning or filing them .. If only we had now what we threw out

I had an enlightening conversation with an emigrated chinese technician last summer .. He said the quality problem is fed by wholesaler demand for imported products at the lowest price possible.. The problem is also fed further when consumer demand for crap exceeds demand for higher-priced quality . He claimed there are foreign manufacturers willing to increase quality if US wholesalers stop spec'ing barely-passable cheap products and we stop buying cheap

I countered we have no choice not to buy crap when most retailers offer no alternative. In his quiet way he tells me "We all have a choice. We can choose not to buy." I suppose this is where i should insert Neil Peart's lyric, "if you choose not to decide, you still have made a choice"

We all could go round and round on politics and here is not the place but there are things our so-called "leaders" did in the 1990's despite opposition and warnings, things that accelerated the loss of US manufacturing and quality .. Many of us are old enough to remember the "Made in Japan" and "Made in Taiwan" stigma when we had better alternatives to buy. Quality loss existed long before the 1990's yet i first noticed loss in "top-name" quality in 1988 on a set of Timken truck pinion bearings.. They weren't stamped "USA" or "West Germany" as expected.. They were "Korea" and sorry to say they lasted 10 months .. I replaced them with NTN's which are still in the truck today.. Left a really bad taste and was the last time i bought timken

Crap is the money maker for the importing wholesalers, with too few exceptions .. And we feed the problem when we buy the crap.. There is a noticeable growing resistance and things will hopefully swing the other way, but it's going to take decades .. In the meantime i go out of my way to make do with what i have or can find made here or in Canada or Europe, as much as is possible

 

[rustystud]

I have no issue with people swapping out for electronics, it's their rig.. However i would have to be dragged right down to a last resort .. I sure agree with you about the lack of points quality nowadays, they are crap .. It's pretty disgusting when "worn-out" 60 or 70-year-old points have more meat on the contacts than a brand new set made of chineseium, not enough meat on them to be worth the time/effort to install..

I only file when i absolutely have to .. Otherwise my US or German-made points get a machinist cloth treatment depending on how much i run them.. Over a dozen operational, all have points manufactured prior the 1990's .. Just think about how many points we threw away over the decades "just because" it was habit to change them out every year instead of cleaning or filing them .. If only we had now what we threw out

I had an enlightening conversation with an emigrated chinese technician last summer .. He said the quality problem is fed by wholesaler demand for imported products at the lowest price possible.. The problem is also fed further when consumer demand for crap exceeds demand for higher-priced quality . He claimed there are foreign manufacturers willing to increase quality if US wholesalers stop spec'ing barely-passable cheap products and we stop buying cheap

I countered we have no choice not to buy crap when most retailers offer no alternative. In his quiet way he tells me "We all have a choice. We can choose not to buy." I suppose this is where i should insert Neil Peart's lyric, "if you choose not to decide, you still have made a choice"

We all could go round and round on politics and here is not the place but there are things our so-called "leaders" did in the 1990's despite opposition and warnings, things that accelerated the loss of US manufacturing and quality .. Many of us are old enough to remember the "Made in Japan" and "Made in Taiwan" stigma when we had better alternatives to buy. Quality loss existed long before the 1990's yet i first noticed loss in "top-name" quality in 1988 on a set of Timken truck pinion bearings.. They weren't stamped "USA" or "West Germany" as expected.. They were "Korea" and sorry to say they lasted 10 months .. I replaced them with NTN's which are still in the truck today.. Left a really bad taste and was the last time i bought timken

Crap is the money maker for the importing wholesalers, with too few exceptions .. And we feed the problem when we buy the crap.. There is a noticeable growing resistance and things will hopefully swing the other way, but it's going to take decades .. In the meantime i go out of my way to make do with what i have or can find made here or in Canada or Europe, as much as is possible

Sadly "Timken" joined the "will it pass the minimum standard" group of manufactures decades ago.
Now I pay a premium for 1970-1980's NOS Timken bearings I find on eBay. Of course that will soon dry up, or already has dried up.
We the consumer had no choice on what parts we bought. I know that working in the vehicle industry since the mid 1970's. We bought what the suppliers had to offer. No choice. "Oh, you're telling me that bearing manufacture is no longer making that bearing, but this one is. OK send it over."
We didn't have the internet back then to do our own searching for parts.
Now we are dealing with the greedy assholes decisions to make more profit over quality.
Now we do have a choice to buy quality parts and products. I for one have been buying "Made in America" as much as I can, or at least as much as I can afford nowadays.
Sadly, "Made in America" doesn't always mean quality anymore either. So I shop around. Germany. England, Japan, these and other countries still try and put out quality products. I actually bought a really high-quality rifle made in Romania of all places !
So look around. Quality is still out there. It just costs more and sometimes comes from foreign countries.

Oh by the way. It looks like "Mount Rainier" is thinking about blowing it's top. That will make things interesting around here ! Better check the air filter in the Deuce.

 

[DUUANE]

Edit: Ok my memory is full of rocks. No oe distributor swaps that work that i can find.
I have used this with great success in one of my M37's.

Electronic Ignition Conversion Kits for 6-Cylinder Autolite/Prestolite Distributors

Electronic ignition conversion upgrade kits to replace contact breaker points in 6-cylinder Autolite/Prestolite distributors in Industrial, Agricultural and Marine Applications

hot-spark.com

They are spec'd by distributor number so an email to them with some pics ciuld get you in the house. There is still the issue with the cap and rotor scarceness tho.
There are aftermarket distributors available for the 302.
I have an externally mounted hei module being triggered by an oe mopar electronic distributor and remote coil on one of my 413 industrials. Head and shoulders above any mopar magic box ive ever run. Starts every time, always stays running.

 

[rustystud]

Edit: Ok my memory is full of rocks. No oe distributor swaps that work that i can find.
I have used this with great success in one of my M37's.

Electronic Ignition Conversion Kits for 6-Cylinder Autolite/Prestolite Distributors

Electronic ignition conversion upgrade kits to replace contact breaker points in 6-cylinder Autolite/Prestolite distributors in Industrial, Agricultural and Marine Applications

hot-spark.com

They are spec'd by distributor number so an email to them with some pics ciuld get you in the house. There is still the issue with the cap and rotor scarceness tho.
There are aftermarket distributors available for the 302.
I have an externally mounted hei module being triggered by an oe mopar electronic distributor and remote coil on one of my 413 industrials. Head and shoulders above any mopar magic box ive ever run. Starts every time, always stays running.

I would love to see your set-up, how you did it.
I wonder if a "crank mounted" type of ignition could be easily adapted to this engine ?
At this point there is not much any of us can really do since parts are not available. We either "reuse" our old parts or find a way to "adapt" something else.

 

[DUUANE]

When i go home ill snap a pic of the big dodge. Nothing high tec..just a piece of aluminum angle drlled for the module mounted with an air gap to the firewall. I used cpu thermal paste between the module and the angle. Ran wires to the coil and distributor..simple pimple.

 

[DUUANE]

This is the basic wiring diagram. (Off the web, mopar elect dist)
There is still the issue of obsolete cap/rotor to solve. I wonder if there is a castable resin with the right properties and enough dielectric strength to make a job of it.
Ive seen the horde advertising some pretty reasonably priced vacuum chambers and pumps lately.

 

[DUUANE]

3M Scotchcast Electrical Insulating Resin 4N-B (Epoxy-based)
Recomended by google. Stable to 194° F. Rated for 8Kv.

Send me some junk parts to dissect. My bro has a couple of 3d printers and an itch to use them..maybe we could come up with a way to fixture and mold a few new bits to try.

 

[DUUANE]

Now we are dealing with the greedy assholes decisions to make more profit over quality

[/QUOTE]


No truer words have ever been said.

 

[rustystud]

This is the basic wiring diagram. (Off the web, mopar elect dist)
There is still the issue of obsolete cap/rotor to solve. I wonder if there is a castable resin with the right properties and enough dielectric strength to make a job of it.
Ive seen the horde advertising some pretty reasonably priced vacuum chambers and pumps lately.

How did you eliminate the points ? What is triggering the module ?

 

[Bulldogger]

How did you eliminate the points ? What is triggering the module ?

There are some solid state mechanisms I've used in motorcycles before. They use a hall effect (inductive) sensor. It is a different situation though, going from two cylinders to 6 or more. I am not as familiar with automotive retrofits.
I am enjoying this thread all the same.
BDGR

 

[DUUANE]

How did you eliminate the points ? What is triggering the module ?

The hot spark syatem is the easyiest. You replace the breaker point plate with their plate with the hall effect switch. Then there is a round cylinder with an internal hex that pushes over the hex that opens the points on the distributor shaft. It has 4, 6 or 8 magnets molded into it depending on the application.

For our stuff you would/could perhaps modify a 6 cylinder hei base plate and/or relctor arrangement to install where the points are. That would certainly trigger the externally mounted module. Just have to make sure you have clearance under the rotor and set the air gap to specs.

 

[DUUANE]

Langdons stovebolt is a great resource for ths topic. The diagram on the left is what we would need to retrofit. This page explains how to line up the trigger wheel with the rotor/cap post.

 

[rustystud]

OK. Now were getting somewhere. This will solve the points problem but what about that silly cap and rotor assembly ? Anyone have a good idea ?

 

[DUUANE]

GM 302 Distributor

Does anyone know what civilian distributor will fit on the M211 302? My truck came with the distributor missing. I heard one from a 50-53 GM truck will work. I don't mind wiring just to test the engine before I would consider buying the 24V Mil. distributor. Thanks

www.steelsoldiers.com

Sounds like it can be done. But not plug and play. Electronic conversion once you got it to fit would be easy with the hot spark stuff.

 

[USMC 00-08]

There is this thread from a few years ago about a Pertronix conversion.

Pertronix Conversion?

Anyone ever done a points to Pertronix conversion on a M35? I have a 1953 Reo M35 with a Continental OA331 Gasser Motor. The distributor is a Delco-Remy M# 1111556, S# 3 B 11, CW Rotation, Military Ordnance # 7762685. Anyone have any leads or ideas on how to and what part numbers to use for a...

www.steelsoldiers.com

 

[rustystud]

There is this thread from a few years ago about a Pertronix conversion.

Pertronix Conversion?

Anyone ever done a points to Pertronix conversion on a M35? I have a 1953 Reo M35 with a Continental OA331 Gasser Motor. The distributor is a Delco-Remy M# 1111556, S# 3 B 11, CW Rotation, Military Ordnance # 7762685. Anyone have any leads or ideas on how to and what part numbers to use for a...

www.steelsoldiers.com

I totally forgot about that post. The problem of the distributor cap still remains though.