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Hello new military vehicle drivin' folks
I FINALLY talked my cousin out of his 51 m37. 24yrs ago he pulled it into a box van and there it sat. Now I have it, and it is an ugly duckling to be sure, but seeing as it was driven in I took the time to carefully get the engine lubed (it was not frozen). Here is the issue it is running a 6volt starter on a 12volt battery with a 12v distributor set up. I had no fire so I ran it back to the coil (12v reading 11ohm). Bad coil. If I put a 24v coil(resistor inside) on it do I have to change anything else? And two: If I get an entire tune up designed for 24v what then?

Welcome DW! Quite a dilema for you to sort out. Are you on the stock generator or is it also 12V? If you're running 12V distributor, generator/alternator and battery, I'd go with a 12V coil and starter, unless you insist on "period correct" which would be to convert everything back to 24V. Do you know if your oil pump was swapped along with the distributor? If not, that will cause problems due to the military distributor having the oil pump engagement "tang" offset, where the civvy distributor tang is centered. A mismatch will cause your distributor to wobble when it's in motion.

Recommend some more research then let us know your findings so we can offer a more informed response.
Gary

hey gary,
It appears to me that only the components of the distributor were changed, I am running a 12v alternator. I do know that a 6,12 or 24 volt coil is no different unless the resistor is located inside - hence the ballast reducers on the fender. I have successfully run any number of combinations, but my choices are limited. the only 12 volt w/o resistor I have found comes from turkey and takes 3mo. to get here. I have not found a 6v, the 24volt w/o resistor cost as much as a complete tune up kit(minus wires) and a 24volt coil w/resistor. I would rather have the whole kit but I'm not sure what I would have at the plug w/12v battery and 24v coil w/resistor, and if I need to add a batt I have a 24v alt w/two outputs, 14v and 28v. I know you are all saying "just buy the 24v w/o the resistor" but I am a miser. REAL QUESTION IS... If I hook up a 24v coil w/resistor to a 12v system will I have enough at the plug, or do I need to insall the 2nd batt and the 24v alt. If only I had as much money as I had brains I'd have half as much as I thought also if anybody out there has any line on a 6,12 or 24v coil (new) W/O resistor I con get for less than 125 bucks let me know.
thanks again gary I should have given more detail... overworked I guess

I would not recommend mixing voltages trying to piece together a working arrangement. You might give VPW a call: this link is to their M37 Electrical parts pages which might help. If not, then I'd give them a call, to explore your options.
http://www.vintagepowerwagons.com/pdf/p ... trical.pdf

Please keep us posted!
Gary

DW:
Post some pics of your "new" rig for all to see.
Ask one of the moderators to help. You could PM
them and ask to post for you.
JB

I have tried a photo, no luck yet. I will get with the referee later but gotta go. However I was presented a solution to my problem by the local guru and I felt kind of stupid afterward. He said and I quote " If you want to buy the 24v tune-up kit because its cheaper... by all means buy it. install a second battery, run it in series for your ignition and pull off one for the rest. problem solved" I have two new ones that won't cost a thing.

DW9 wrote:I have tried a photo, no luck yet. I will get with the referee later but gotta go. However I was presented a solution to my problem by the local guru and I felt kind of stupid afterward. He said and I quote " If you want to buy the 24v tune-up kit because its cheaper... by all means buy it. install a second battery, run it in series for your ignition and pull off one for the rest. problem solved" I have two new ones that won't cost a thing.

Don't bother with feeling stupid unless you actually decide to follow this guys analysis. This local guru isn't offering good info that will work well for you. But with your apparent mindset, (if I'm understanding this correctly) it may not really matter. Obviously you don't want to spend the cash (for whatever reason) it takes to install a correct 24-volt system, or a correct 12-volt system. It isn't smart to try and mix the 2 systems, go 1 way or the other completely.

Here is some good advice for you, now granted it isn't likely what you want to hear, however it is the best advice anyone can offer concerning the issues you have. Forget about getting this, that, or the other parts that will only complicate the apparent conglomeration you already have that doesn't work. Save your $$ until you have enough to get what you need to do this right, then go for it.

The 24-volt original system is by far the better, more reliable system. Electronic, pointless ignition is available for it, and is a great upgrade. Converting to all 12-volt is doable, but the end result is not as durable or reliable as the original system. Now you have the facts that will guide you toward a good solution to your problem; how you use the information, or not is of course totally your call.

Charles now you have me curious or maybe I am just misunderstanding something. Are you saying the 12V electronic ignition is not as reliable as the 24V electronic ignition? If yes then what makes the difference from a technical perspective? Another question, is the 12V electronic ignition more reliable that the original standard 24 volt ignition? I hear these negative stories about 24V coil and condensers that are being currently produced are junk. I assume the old stuff is all used up. I hear stories that the electronic ignition gives a hotter spark and is "fool proof" (whatever in the world that might mean) or maybe it is failure proof compared to new beaker point systems. Can you condense all the hooplah into a list of pros and cons vs. anecdotal heresy? Thank you.

Sure it is harder to get top quality parts these days for almost anything, that is common knowledge. As far as the electronic module units, both 12 and 24-volt units are of equal quality, but the 12-volt civilian type systems overall are simply not the quality, nor was it meant to be as reliable as the mil spec system was designed to be. That too is common knowledge. The 24-volt coils that are replacements actually have a pretty good track record when you consider how many are out there in service. If you are asking if they are as good as what we used to get that were the actual mil spec coils, probably not, but the simple truth is those are hard to come by, or I might say virtually impossible to find at any reasonable price. Most vendors who claim to have a few new ones left have them priced at $150 or more. Electronic units have no moving parts, thus they are not prone to mechanical wear like points systems are. Neither points or condensers are used with the module kits, so that does away with 2 trouble prone, high maintenance items. The module, being a sealed component is not susceptible to corrosion like points are, so they are much more reliable as a result of these things, especially if you are in an environment where high humidity and corrosion are a big factor. Nothing except what God has made is "fail proof", but this is about as close as it gets in a mil spec ignition as compared to a points type system. It isn't totally maintenance free, but again this is as close as it gets with much less routine maintenance being required. My experience is yes the electronic system can offer a hotter spark, but only if the entire system is in top notch condition. Installing a module kit into a distributor that is significantly worn or isn't up to par in all other areas will still produce a substandard unit. All distributors we install in our shop are totally rebuilt, very seldom do we find one that doesn't need something more than just a module kit installed. Honestly the vast majority do need a total rebuild to upgrade them to the best they can be.

Hope I've answered you question satisfactorily, if not just provide more detail and we'll try again.

In a nutshell a electronic module won't fix a worn out military system. Why not just rebuild the 24 volt factory system ? I like stock trucks .

DJ wrote:In a nutshell a electronic module won't fix a worn out military system. Why not just rebuild the 24 volt factory system ? I like stock trucks .

You might want to read my post above 1 more time as I've already answered your question.

Let me address this once more, total rebuilds repair totally worn out components bringing them back to original or better than new stock condition. An electronic module kit replaces the points and condenser with a sealed unit that has no moving parts, requires no adjustment, cleaning, or interior routine maintenance after the initial installation. It is not a miracle cure in a box for everything distributor related. A new module kit does not address possible wear in the other areas of the distributor, such as worn shaft bushings, bad oil seal, worn rotor, worn inner cap, or a bad coil in units that may not have been maintained properly or are just worn out due to use and old age. I spoke about making a unit "the best it could be." You say why not just rebuild it to factory original stock condition? You can do that, but it will never be the best it could be. The electronic module kit is an upgrade that is a vast improvement over points. Points are subject to mechanical wear and corrosion issues, and will require certain periodic maintenance with cleaning, adjustment, and replacement. Sealed modules simply require correct initial installation and that is it for the life of the unit. The vast majority of the units we have installed or sold for DIY installation are still in service today, years later. Like I said in my first post, only God makes "fail proof" things, and I have not seen any module kits that were made by God, so they can eventually wear out and need replacement. They have a 30-month manufacturer free replacement warranty, I've seen only a couple fail out of hundreds sold. We have many that were installed 10 years ago, which is how long we have been selling them, that are still functioning perfectly.

The better system is a totally rebuilt stock military spec unit. The BEST system is a totally rebuilt stock military spec unit that has had the electronic module upgrade kit installed in it. The key here is whether you want "BETTER" or "BEST."

I think I understand what Charles is saying. Best is a totally rebuilt unit with electronic ignition But how does that solve the coil problem. It sounded like you still have to use the original type coil and if most of the current manuafatured coils out there are of poor quality aren't you still at risk for that to fail OR does the electronic ignition system come with a a new differant coil that is of much better quality. Sorry for being a little dense here but trying to make sure I am not assuming the wrong thing. Thank you.

No coil is included in the module kit. There is the one source wholesaler that is having the mil spec coils reproduced. I have never had a bad one from them personally and we have a lot of them out there. There were some early repros out there several years back that were crap from the word go. They faded away fairly soon after their arrival. I think some have the repros we get today confused with the others that are now gone away. Today's repro coil is much better; they are all imports. I'd be the first to say I'd rather have a US made coil IF I knew they would be a quality part. Truth as we all know is much US made stuff these days isn't any better than the imported stuff, in some cases I'd go for the import over the US. It hurts my feelings to say that, but it is the simple truth. We have had good luck with our rebuilt distributors, so I can't really complain. In my honest opinion, we are extremely fortunate that anyone is reproducing the mil spec coils at all. It certainly is not a huge marketplace for them like it was at one time. The military hasn't used them in 20 years or longer, so individuals and a few builders like us are the market these days. Looking forward, I'm doubtful we will see this situation improve.

"In a nutshell a electronic module won't fix a worn out military system. Why not just rebuild the 24 volt factory system ? "

Wasn't really a question,as it was a statement. If all you want to do is eliminate maintainence on the points system,witch in my very humble opinion is not that big of a job then maybe you own the wrong vehicle. Any old vehicles like these need periodic maintainence,it's the nature of the beast. I don't see where the module will be a great time saver,of all the maintainence on the vehicle ignition has to be the easiest and cleanest to do. I guess being old and having trucks of this vintage for making a living with and as daily drivers through the years, the points ignition don't scare me. If convenience and time saving is what a person is looking for maybe a Toyota truck is what is needed. I know a person should not question the esteemed guru's of the forum ,but I'm only offering my very humble opinion.

DJ wrote:"In a nutshell a electronic module won't fix a worn out military system. Why not just rebuild the 24 volt factory system ? "

Wasn't really a question,as it was a statement. If all you want to do is eliminate maintainence on the points system,witch in my very humble opinion is not that big of a job then maybe you own the wrong vehicle. Any old vehicles like these need periodic maintainence,it's the nature of the beast. I don't see where the module will be a great time saver,of all the maintainence on the vehicle ignition has to be the easiest and cleanest to do. I guess being old and having trucks of this vintage for making a living with and as daily drivers through the years, the points ignition don't scare me. If convenience and time saving is what a person is looking for maybe a Toyota truck is what is needed. I know a person should not question the esteemed guru's of the forum ,but I'm only offering my very humble opinion.

It doesn't hurt my feelings if you want to go around the world to get across the street, that's up to you.

What sold me on the low maintenance issue is using this system in fire dept. brush trucks. We all know trucks in fire service need to roll when needed in a moments notice. I've been called to fire stations when engines fail to start, numerous times corroded point contacts were the culprit, in fact I venture to say out of all calls such as this, points with corrosion ranks very high on the list of sole issue non start conditions. When the electronic units came along, we were anxious to try them out in fire truck applications. The non start issues ceased, I can't remember the last call we had for a non start. We have high humidity in the summer months, that promotes corrosion on points. Most people would rather drive with confidence instead of wondering what they will have to do to get it started today. Needless to say, I quickly became a believer in sealed ignition units.

By the way, I never have seen a brush fire fighting unit mounted in the bed of a Toyota truck, so until the trend changes, one of our major jobs is to find better ways to keep the older units operating in a reliable fashion. These electronic ignition modules have brought us a long way toward accomplishing that in trucks that still run the gasoline engine.