Technical Weak 6 volt spark. I want to hack in an MSD box...

Hey guys, I'm trying to start my old '50 IH L-122 truck with the original 6 volt, positive ground system. I have replaced the following:

* Points & condenser
* Cap & rotor
* Plug wires
* Spark plugs
* New 6v battery

The spark output seems weak. The engine cranks and kinda wants to start, but it wont catch (sitting way too many years). I don't want to keep taxing the original starter to make this happen. I'm thinking about hacking in a MSD 6A box to give the ignition a major boost. This is only temporary to get it to fire up. Once I get her running (with good oil pressure and no strange sounds), I will feel more comfortable spending money on it.

I plan to keep the MSD box separate from the vehicle, I will also use a separate 12v battery and a 12v coil as well. I have these items.

I have some ideas on how to do it, but I wanted to post this question to you people before I share my plan - to get a different perspective and all.

Here is the MSD instruction manual.

Thanks!!!!

http://www.g3ignition.com/images/MSD 6 Series Installation Instructions.pdf

BTW, I called MSD tech this morning. They said it was impossible.

 

I'd just put the 12v battery in it, remove the fan belt, connect the battery only to the coil and starter, and fire that puppy up.

 

I tried doing that. No help. I didn't like the burning smell either

 

You might want to figure out what the problem is, then....what sort of troubleshooting and testing have you done? Compression test?

 

There is a technical reason somewhere why the spark output is weak, make sure the ground cables are fresh, of sufficient gauge for a 6 volt system and they aren't loose or the connections corroded.

 

Battery cables good with good connections. I haven't done a compression test yet.

 

Also, what was causing the burning smell when cranking it on 12v? You do have to limit cranking time, to short bursts, to avoid overheating the starter. And don't leave the power wire to the coil connected, when it's not being cranked.

Let us know how much compression it has...

 

I'm guessing the smell is coming from the starter. It's not bad, but its noticeable. I've been trying to limit the starter use. The original manual says 30 seconds, so maybe 12v would be 10-15 sec

 

yes, at most.

 

Maybe if I isolate the starter circuit from the rest of the truck and hook up a 12v battery with the ground going to neg? I then would hook up the MSD via the points method. So essentially, the trucks harness would not be hooked up, only the 12v battery, starter, and the MSD. I would need to add a jumper wire to the solenoid.

Would I damage the starter or solenoid with the polarity reversed?

 

that sounds like a good way to get the MSD going. I think you still need to figure out why it won't run first, though...

 

Are you sure youre not using resistor core wires, or a internally regulated coil ? These things will kill spark.

 

Since my gramps had an International dealership, I was around a variety of those old Binders, and they usually started very easily. I for one do not trust new manufactured condensers these days, in fact I quit replacing condensers in the 70's after getting a couple that didn't work out of the box, and realizing that they don't generally "wear out". Might try putting the old one back in. I also work on a lot of antique tractors with low compression ratios, and if they have been sitting a long time, can be tough to fire off the first time- duh- deduh- deduh- deduduh- dededuh- until they finally wheeze into life, and start fine after that. Might try a little Seafoam in the cylinders to help the old rings a bit. Does it have brakes? Sometimes a wheezer will light off with a tow start

 

Replace the coil with a known good unit, and watch the sparks fly.

 

That'd be my guess as well.

 

So it turns out that old farm trucks really like 12 volts and MSD boxes

Also, the reason it wasn't starting before was because the exhaust was full of acorns.

 

Link won’t play

 

Try it now...

 

Nice.

 

I think you will find that that truck will start just fine on the original system, without the acorns lol

 

In that size truck, probably a BD220 or BD240- sweet runners

 

The video look like you might have a head gasket problem.

 

The smoke implies acorns might not be the only issue.

 

1950 IHC would have the new for 1950 Silver Diamond 220. I have a Silver Diamond 220 in my 1953 IHC R-130 dump truck, 5.67 to 1 rear axle with a non synchronized four speed.

 

Grab the rotor in the dizzy and see if you can wiggle the shaft. Worn bushings will change the point gap when its rotating, from what you measured while still