12V conversion - Engine cuts out

[HeyObie]

I choose to convert my 1950 side mount 8N to 12 volt. The old generator was dead and probably needed a new regulator.

So anyway, I ordered a 12 volt system and installed it. Tractor starts fine, it charges, runs for a couple minutes and then cuts out.

I keep the 6 volt coil and installed the resistor.

Before I converted, the tractor started and ran strong. It just didn't charge.

Any thoughts? Thanks
 

[Jim in Eastern NC]

Perhaps your coil was on the borderline of being defective, and the higher voltage before the resister heats up is just too much for it. I expect you'll be fine with a 12v coil.
 

[HeyObie]

I ordered a 12 volt coil yesterday just to have everything brand spanking new.

When I install the new 12V coil, I assume I remove the resistor? Is this correct? Thanks again
 

[Jim in Eastern NC]

You'll find differing opinions on this, but I ran a 12v system with a 12v coil for years with two resistors, the ceramic one and the coiled wire version, in series. And it cranked and ran fine and points lasted several years. Last year, I converted further to Electronic Ignition, and I'm pleased with that, too (but I saved my points plate just in case!). Mine is a 48 8N. I don't think you're risking much either way, but I would use the resistor you bought, and I expect it'll run fine.
 

[HeyObie]

Thanks Jim.

The front mount 8N's have a coiled resistor. The side mounts have no resistor.

So on a side mount, with a 6 volt system and a 6 volt coil, there is no resistor. So I imagine that a side mount with a 12 volt system and a 12 volt coil, no resistor is required.

I'd rather not have anything extra hanging on the 8N if I don't need it.
 

[Mike Groom]

I would use the resistor between the coil and the dist.,it will drop the voltage to the points and extend there life.
 

[Texas!]

As long as your new coil is a true 12V coil marked "12V No External Resistor Required" you'll be OK. A lot of supposed 12V coils are actually 6V coils and there is a high resistance wire in the vehicle's electrical system to compensate.
 

[old]

First thing to do it simple trouble shooting no ifs and or buts about it. Check your spark could have a loose wire some place or the ignition switch maybe going bad. You need a blue/white spark that jumps a 1/4 inch gap or more. Next check fuel flow. Just because it ran well before you messed with it does not mean it did not have a problem waiting to kick up in the back sides.
As for the coils a 6 volt coil on 12 volts needs a ballast resister. But if you buy a 12 volt coil and it says no external resister needed then you do not need that ballast resister, but note not all 12 volt coils are in fact TRUE 12 volt coils and some say to use a ballast resister
 

[Dell (WA)]

Obie.........you complain......."So anyway, I ordered a 12 volt system and installed it. Tractor starts fine, it charges, runs for a couple minutes and then cuts out"........couple minutes of runtime is almost always a BAD condenser. Condensers can be BAD right outta the box. Most are good fer at least 100-volts but the way they are manufactured can be BAD rite outta the box. Do I haffta tell you to chance yer condenser??? You doubt??? Re-install yer OLD condenser.

Recommend using a real 12-volt coil, NAPA IC-14, uses NO resistor ever. And is even has HOTTER sparkies ........Dell, yer self-appointed sparkie-meister
 

[Kurt-NEPA]

Make sure you get a 12 Volt coil that says "No External Resistor Required". Then ditch the step down resistor. I never liked those things anyway.

Do yo have a ballast resistor in the system in addition to the step down resistor? If yes, use the 12V Coil No External Resistor Required" and ditch both resistors.

I would do the coil swap first and then see what happens. I would use a 12V coil anyway, so it only makes sense. If it still cuts out, I would check the ignition switch, condenser, and points.
 

[souNdguy]

you are compairing apples to oranges and thus providing bad info.

there is a WORLD of difference in a 12v round coil and a 12v square coil.

the 12v square coils for the FRONT mount machines REQUIRE an external resistor.

the 12v round coil foor the side mount ignition does NOT require an external resistor.

relating experionce of one to the other introduces false info...
 

[souNdguy]

got spark at point of stall?
 

[Kurt-NEPA]

Sounder - I believe there are two types of round can 12V coils. One requires a ballast resistor and one does not.
 

[Dell (WA)]

Kurt........would you believe ennytime a coil requires a "ballast resistor", it is NOT a true 12-V coil. Ittza LAW; Kerchoff's Law. ........respectfully, Dell, Ret Elect Engr
 

[Kurt-NEPA]

Yep Dell, I believe that. 12V means little, its those little ohms that matter. They stay constant. But as Volts go up, Amps go up. That is until things burn up. V=IR.

Kurt - Retired Metallurgical Engineer.