What all do I need to crank start?

[Alex M]

I'm working on my grandads 1950 that hasn't run in about 30 years and I dont want to spend all the money on a 12 volt system if I don't have to. If I plan to crank start it, what all in the electrical system has to work? Please bare with me I'm new to this stuff.

[Peter Person]

Alex,
You need to re-read some of the responses in the other topic you posted.
Glen,Waif, and Eugene pointed you to important items to consider.
To answer your specific question, do you have a magneto or battery ignition?

[Alex M]

Alex,
You need to re-read some of the responses in the other topic you posted.
Glen,Waif, and Eugene pointed you to important items to consider.
To answer your specific question, do you have a magneto or battery ignition?

I have read them and will again, I'm just thinking ahead for what I am going to need. I'm pretty sure I've got a magneto.

[Glen]

Hi,
If you are hand cranking the Cub, all it needs is a magneto that works well.
The magneto makes it's own power, and is not connected to battery power.

It is supposed to make a good blue spark so the engine will start well, and run well.
You could test it's spark, the spark in the spark plug wires should be blue and jump a 1/4" gap.
A yellow spark is weak and needs improving, the engine may not run with a yellow spark.

The ignition points get old and burned from use, and can make the spark less than it should be.
A bad condenser can cause a poor spark.
The magneto coil can go bad, and not work right.

TM Tractor has magneto parts, you can look at the pics of them.

The Battery Ignition unit needs a battery to make the coil work.
It doesn't make it's own power.

[Eugene]

Don't get ahead of yourself. Is the engine stuck? Can you hand crank the engine?

COMPRESSION. Need compression on all cylinders. Dry compression test then wet test - record the results. Hand cranking the engine, you need a minimum of 50 psi on all cylinders.

Work order. Establish compression, then carburation, lastly ignition.

Do not purchase any parts until you know what the problem is and how to solve it.

[SamsFarm]

Most important, you'll need the hand crank! And a safe technic to use it!

Magneto will work without a battery.

A regular distributer & coil will need some voltage from some sort of power source, (battery, battery charger, jumper cables).

[k hutchins]

IMHO
Points, plugs, and condensor are fairly inexpensive and easy enough to start with. You can even dress (file) the existing points, and adjust the gap. Then clean and regap the plugs.
Of course fuel and compression are important as well, but if you're just checking the mag to see if it's servicable, this is where l would start. Cleaning the inside of the cap and checking the rotor for timing marks will also help.
Also, don't for get to prime the oil pump. Then review "How to" threads on handcranking. Keep your thumb on the back side, 1 revolution at a time with a sharp upward stroke.
Assuming you have "decent" compression and fuel flow, you should be able to get it to "cough" a couple times even if it doesn't start. This can point you in the directions you need to pay attention to for start up.

Good luck
Hutch

[Rick Spivey]

Don't snap the magneto over without giving the spark a place to go, that can burn out the coil. I would disconnect the coil wire (goes from square cap to distributor tower), and check for spark against a grounded surface like the engine block. Of course, that requires two people when hand cranking. If you get a blue to white spark there, then proceed to check spark at each plug. If you don't then the magneto needs some service. Set the engine to TDC on cylinder 1, remove the magneto, and start asking questions. Magnetos are a bit mysterious to most folks, and a special tool is needed to take them completely apart (if needed).

[Clemsonfor]

I'm working on my grandads 1950 that hasn't run in about 30 years and I dont want to spend all the money on a 12 volt system if I don't have to. If I plan to crank start it, what all in the electrical system has to work? Please bare with me I'm new to this stuff.

If it's a 6v , there is no reason to convert it if your stuff works as is. But really to answer your question you just need a crank. Turn the switch on, set the throttle and maybe choke, maybe not? And MAKE SURE ITS NOT IN GEAR!!!! Then just crank it swiftly good a few times.

I should also say that you need a battery withatleast some voltage in it of it's a battery ignition. But I read you have a magneto in a later post so ignore this.

[Stanton]

Here's the proper way to hand crank/start a Cub. Found in our Video library: How to Hand Start a Cub

[SONNY]

A crank and if you value your hands and arms---- you wont do it !! --- pull start that sucker! and be safe! Good luck on your venture!

[Urbish]

If you get her dialed in, crank starting should be as easy as this:

[Completeihnut]

Thanks for all the information. Let me recap... Good compression,,, Drained fuel, cleaned fuel line and bowl (screen and openings clogged.. soaked carb in cleaner and rebuilt.. getting fuel but no spark.. IT DOES HAVE A MAG - H-4. With help from Jim Becker got to points which look good. Want to replace and do condenser while I'm there but cannot get it out..

Have removed the cover, the bake lite insulator but there is an inside insulator that I'm cannot tell whether it should go in the hole or come out. Also the coil wire is connected to it. what is the best way to disconnect that.

Lot of questions but rather get info before ruining something that I can no longer get parts for.


Thanks in advance

Warren

[Don McCombs]

What model tractor are we discussing now?

[Glen]

Hi,
You probably know a Cub uses a J 4 magneto, which is different than a H 4 magneto.