M135 Just shut off !! ??

[Brad]

Howdy friends,Been awhile
since I have had reason to visit the web site.M
y Son was just taking my Dad's M135 for a spin here this evening in preparation for the local Fall Festival parade this weekend.Wel
l, it just shut off and quit running as if you had turned off the switch.
I checked and it is getting plenty gas.
Looked as best as we could in a few minutes and there are no loose or broken wires.
So I took off the distributor cap and everything looked fine.Then I
found that the post would turn on the "PRIMARY CIRCUIT RESISTOR""
At first I thought the nut was loose cause it would turn. But the nut was not loose, the whole thing was turning.I
took it apart and the porcalin is broken.The
wirs spring like coil is intact but the porcalin is broken off.
I would think this is the trouble, but have no idea how it would have happened????
Where can I get a new one, and might this not cause the truck to quit running??Th

Thanks in advance
Brad Foust



ny ideas where I can get a new one?

 

[NDT]

Nobody has new ones but take offs might be available from White Owl Parts.

 

[Brad]

thanks for the reply

 

[pjwest03]

If the ballast resistor is open there will be no power to the ignition coil.

If someone knows the value (ohms) for the resistor we can likely locate a modern replacement that's more readily available.

 

[Brad]

is the "Ballast Resistor" another name for the "Primary Circuit Resistor" as it is called in the manual??
Where could I find that value in ohms as you suggest?
I really appreciate this help.

I am off now to search my parts for another disrtibutor which might have the resistor in it yet.
I do have one somewhere, hope I can find it, them hope it has one in it, and finally, hope it is a good one!!
Wish me luck, please.

 

[USMC 00-08]

I am almost certain that Memphis Equipment has those. Call them. They don't list much online.

It would be neat to find a modern replacement too. Please let us know what you find if you go the modern replacement route.

 

[Brad]

Friends<
My dear old Daddy and I restored this truck some 8 or 10 years back. Soon after he has a sroke and after 3 1/2 yrs of my Brothers and I taking care of him we lost him. We will never get over it.
But he wanted this truck to ride veterans in in any parade we could get it to.
So my Son and I have decided to keep it going as long as we can and get to as many events as we can.
We make several or more each year and other than chronic brake problems (locking up) we have had no trouble.
This is the first time it has left us sitting.
My Dad was a Korean War vet with seven battle starts, Inchon and the Chosin among them, and he would be appalled by this BS going on right now. All the more reason to keep this truck on the road.
My Son is an Iraq War vet. Hense his interest.
Anyway, lo and behold I found our electical parts boxes and there were two distributors in there, and in a little plastic container I found the exact part we need, almost looks new.
My question is if there is any way to test these???
And I'd still like to get another for a spare.
I will be calling Memphis and those other places I found on google.
Thanks again for the help and I'll let ya'all know how we do her this morning??
Again, wish me luck!!
Brad

 

[pjwest03]

You can test it with a digital multimeter, measuring across the posts I would expect a value in the neighborhood of 1.5 ohms could be a bit more or less. 0 ohms would be a dead short and getting no reading would indicate that its an open circuit like the one you were having issues with.

 

[pjwest03]

is the "Ballast Resistor" another name for the "Primary Circuit Resistor" as it is called in the manual??
Where could I find that value in ohms as you suggest?
I really appreciate this help.

I am off now to search my parts for another disrtibutor which might have the resistor in it yet.
I do have one somewhere, hope I can find it, them hope it has one in it, and finally, hope it is a good one!!
Wish me luck, please.

Yes, ballast resistor is the same as primary circuit resistor. It is in a series circuit with the primary side of the coil. The purpose is to control the amount of current flowing through the coil. The coils were not designed for the full 24 volt supply, so an external part was added. It's also pretty common in cars after the 12v conversion as the original coils were designed for 6v systems.

 

[Brad]

Ok Guys,
As I said, I had found a near new looking resistor and installed it.
NOTHING!! Wont start.
I took the cover back of and checked for sparking at the points. Yes, there is spark there.
Then I found my multimeter which I really dont knnow how to use.
I put it on a setting that said 9V.
Where the wire goes on the resistor we're talking about, first it goes to 17, then settles on a, but not like one volt. It's a one with nothing where the ")" would be if it were a 10. I hope ya know what I'm saying.
Oh, first I check my batterys with the meter and it was 12.32 or something like that, so I assumed I had it correct.
Anyway after I checked all that stuff I noticed that the pole on the resistor was pretty hot. I guess it is supposed to get hot, but only after a couple minutes.
I also checked the + pole on the coil and it was 4. something??
Could this coil be bad?
There are only the capacitor at the points, and the capacitor at the ignition coil???

Anyone have a phone number I could call with questions so as to save some time??
Thanks

 

[snowtrac nome]

On the plus side of the coil you should see battery voltage, on the negative side with points open you should see battery voltage, with the points closed you should read 0. the next variable is coil saturation, the gap on the points I think should be 18 thousandths which should give a dwell angle of 28 to 32 degrees. sorry if I'm wrong I'm trying to go from memory been a while since I worked on a spark ignition vehicle. the bottom line if you don't have the proper saturation the coil wont work. also look inside your distributor cap and rotor for carbon tracks indicating cracks that will leak voltage in the secondary ignition system back to the primary side the positive side should see 12 volts at the positive terminal and if the points are closed it will drop as the resister warms up.

 

[dmetalmiki]

You can, Take a spark plug out. Remove the distributor cap and rotor arm. Turn on the ignition, Place the rotor arm in the distributor cap with the brass top contact pressing on the carbon contact, while "pointing/aiming" the end of the rotor arm at the contact from which the wire goes to the spark plug you removed (sitting somewhere nicely earthed.)..It does not matter if there is NO gap between the rotor carbon and the chosen cap segment. Now use an electrical screwdriver and flick open the points. If they are already open just jab the screwdriver at the the gap momentarily bridging it. You will see a spark at the plug now resting earthed. NOTHING?..your 'points' are Carbon'd up and require stripping and cleaning (sand stoning CLEAN and LEVEL.). Make sure you don't short out the points when assembling. As the "free to open and move" arm only creates a spark as it earths (it is isolated) by small bushes on it's post, to where the power and condenser wires fit.
Personally, To make the circuit less complicated I always remove the ballast resister and simply put in a battery voltage coil.

 

[Brad]

Guys, I appreciate the help. I need it. This thing sill will not run. Not a putt! Crank all day, nothing.
That's how it shut off, it was running perfect as it usually does and it just quit.
I have changed the coil, the ignition coil capacitor, the primary circuit resistor, the primary circuit capacitor. And it has made no difference.
I changed them all one at a time and then back again as there must be nothing wrong with the originals??
As I said before there is spark at the points.
But I pulled a plug and held it on ground and had my Son crank it. NO SPARK seen at the plug???
I thought the points may be worn or somehow had moved, but I checked them and the gap seems perfect at.022 as stated in the manual.
I have not changed the breaker point capacitor. Could this be the culprit??

Now tomorrow I will check the voltage at both sides of the coil as suggested. But what battery voltage should I want, 12 or 24 volt??
( I thought that resistor was meant to lower the voltage??)
And if I do not read what you advise, what is the cause??

I have spent about all day on this and am getting no-where fast. Got rained on two or three times, wet and ugly.
This is just not making sense to me??
Thanks so much to everyone
Brad

 

[doghead]

Yes, the points capacitor could be your issue.

It may be shorted.

You can simply disconnect it, and see if you have spark (at the plugs), but don't run it like that. replace it if it's bad.

 

[Brad]

Just this evening at Church a fella there that is pretty knowledgable suggested a bad rotor?
He said that if the rotor had that little short diod or what ever that thing is, he has seen them cause my problem, if burned out??
And comments?
Tomorrow I attack again, but my time is pretty limited tomorrow.
Thanks so much to all, I very much appreciate it.
Brad

 

[USMC 00-08]

Hopefully it is just the rotor. Let us know what solves the problem.

 

[Brad]

Well friends, first thanks for all the advice.
I finally gave in and took my old Garand and just shot the truck to pieces. I have had enough of it.

No, not really, though I have someimes felt like it.
I have to remember to try the easiest fix first.
I was able to get a little time and I changed the rotor. Started right up immediatley. Runs like a top, as it always have.
After changing all those parts, I should have tried it first!!!
Brakes still hanging up though. They have done that ever since we have been working on it.
I do not know what the problem is.
That is for another day.
Thanks so much to all.
My dear old Dad would be appreciative!.
Brad Foust

 

[USMC 00-08]

I think you either have a problem inside your airpak, a restricted brake hose or there is a check valve in your master cylinder for those brakes to be hanging up like that.

 

[Brad]

I have had the airpac rebuilt, twice.
Have rebuilt or replaced ALL the wheel cylinders.
Have replaced with new, all the flexible brake lines.
Have pulled those heavy wheels, adjusted and bled the brakes a trillion times.
However, one of the first things my Dad paid a guy to do was rebuild the master cylinder. Every now and then I hear a rumor of a check valve in the master cylinder?
Why oh why would there be such a thing. And if I take it off, what do I look for to know that has been the prblem.
Here is how it acts.
Driving along normal. Use the brake and it takes several seconds to release. Then once released seems loose enough.
Why I doubt the master cylinder or air pac, seems to only be the front wheels that lock up, and usually the drivers side only???
Thanks

 

[USMC 00-08]

This is how your master cylinder should look inside.



If it has this in it, take it off the spring.