Need help on cub

Tue Feb 04, 2014 10:22 pm

I have A cub that someone tried to run on 12 volt with 6 volt gen so I converted back to 6 rebuilt gen new voltage reg and batt ran before now it won't fire has spark but not very hot carb may need rebuilt but it won't even hit on either I have no clue where to go from here any help is appreciated thanks in advance

Re: Need help on cub

Tue Feb 04, 2014 10:54 pm

Check the coil if there is weak spark. Did you do a complete tune up yet, if not maybe a good time too. My thoughts.

Re: Need help on cub

Tue Feb 04, 2014 11:10 pm

No I haven't done a complete tune up yet was planning on it just wanted to get running first it has 12 volt coil on it I heard you can run that on 6 volt not sure and also it has what looks to be a condenser hooked to one of the coil terminals not sure about that to thanks

Re: Need help on cub

Tue Feb 04, 2014 11:21 pm

Are you sure that "condenser" isn't an external resistor? If it is you need to remove it.
Also make sure the coil doesn't have an internal resistor.

Re: Need help on cub

Tue Feb 04, 2014 11:40 pm

Ballast resistor wired in series to coil. Remove. Resistor will drop the voltage at the coil by about 50%. Probable source of weak spark.

One more thought, some 12 volt coils have an internal resistor - also designed to drop the voltage.

As Jason suggests. Complete engine tune up including compression tests.

Re: Need help on cub

Tue Feb 04, 2014 11:46 pm

Ok thanks I'll try taking off resistor it looks just like a condenser on a small engine but I'll try that it ran descent before I rebuilt gen I teased it and reg so it should be good to go is there a reason they would put that resistor on when they were trying to pump 12 volts out of gen

Re: Need help on cub

Wed Feb 05, 2014 9:50 am

Chase wrote:is there a reason they would put that resistor on when they were trying to pump 12 volts out of gen
To operate the same appliance; lights or starter, 12 volt systems operate at a lower amperage than does a 6 volt system. Lower amperage means the manufacturer can use smaller diameter (copper) wire to do the same work.

Ignition systems using points, operate within a 4.5 to 9 volt range. Manufacturers utilized a system to drop the battery voltage to around 6 to 9 volts at the points. Some manufacturers use the ballast resistor, others a resistor wire, and some used a coil with an internal, built in resistor, to drop the electrical system's voltage to the points.

Re: Need help on cub

Wed Feb 05, 2014 10:13 am

Chase, how about a picture of your distributor and the condenser. the condenser on a distributor is normally on the inside and very small. If it was 12 volts, it would either have had a 12 volt coil or a 6 volt coil with a ballast resister in series with it. The resister is normally a ceramic about 1/2 square about 1 1/2 inches long with a terminal on each end and frequently mounted under the edge of the hood or on the side of the coil. Trying to run a 6 volt system with a coil that is set up for 12 volts will give a very weak spark, as you described. any chance it has a magneto with an external coil? Magnetos are more boxy shaped while distributors are a round or cylinder shape, depending on your point of view.

Re: Need help on cub

Wed Feb 05, 2014 6:37 pm

It has distributer and d16y champion plugs it won't let me upload pic if you give me email I can send that way thanks

Re: Need help on cub

Wed Feb 05, 2014 8:37 pm

ejpuckett@centurytel.net

Re: Need help on cub

Thu Feb 06, 2014 11:41 am

Here is Chase's distributor. It definitely has an external condenser added to the dist. side of the coil. Also, I forgot to mention, if you put the battery back to + ground as original be sure the + side of coil is going to the distributor. In my personal experience it makes very little difference in the strength of the spark, but does make a difference in the length of life of the coil, and possibly the points, but not much experience int the points part.

Image

Re: Need help on cub

Thu Feb 06, 2014 4:48 pm

If you can't find a white ceramic device in the wire running from the ignition switch to the coil, then it is one of two things:

1. It is a 12V coil and provides a weak spark on 6V.
2. It is a 6V coil that has been run on 12V, and is burned out.

Either way, you need a new 6V coil.

Re: Need help on cub

Thu Feb 06, 2014 6:46 pm

Ok we'll there is no resistor in that wire so I need a 6 volt coil and also the internal condenser is missing will it work like this it's hooked on neg side of coil

Re: Need help on cub

Thu Feb 06, 2014 7:27 pm

Use the proper condenser, in the proper place inside the distributor. The NAPA number is ECH IH200.

Re: Need help on cub

Thu Feb 06, 2014 7:39 pm

Chase wrote:the internal condenser is missing will it work like this it's hooked on neg side of coil
Yes. No problem. The condenser does not have to be installed inside the distributor.

My guess, the correct location, inside the distributor, is a pain in the butt to install without the removal of the distributor.