[bowtiebuster]

Hey all,

I'm really having trouble setting the edge gap on my '66 MF-10. It's a magneto ignition engine with S/G.

I believe that to set the edge gap for the coil / magnet on flywheel I must leave a .020 gap from the first pole of the coil. The points are supposed to begin opening at this time, yet they are opening when the magnet is almost past the second pole of the coil. Somethings really not right.

Does anyone have experience with these magneto cast iron tecumsehs? Please help, I don't want to rip the motor out and replace it but my patience is wearing thin.

Please help.

Bowtiebuster

 

[MH81]

A business card is how I've set all my magneto air gaps on the Teccy engines. As for the points, I think they are supposed to be at about 20 thou.

Here is a manual for the MF10 & 12 tractors

http://gardentractortalk.com/forums/files/file/3872-tecumseh-repair-and-service-manual/

And here is a manual on the Tecumseh

http://gardentractortalk.com/forums/files/file/3872-tecumseh-repair-and-service-manual/

they are both sizable.

EDIT:

Here is the spec page with the gaps. (from the first link)

View attachment 94768

 

[bowtiebuster]

Thanks for the info MH81!

Im still thinking I have a problem with the timing. Attached is a pic to better describe what I'm asking.

 

[MH81]

As long as the key is good in the flywheel and no one has messed with the timing of the cam, it should be right... Barring twisted crank or something.

Are you getting spark?

 

[bowtiebuster]

I'm getting zero spark. I replaced the condensor as the old one was damaged. Points were cleaned and adjusted to spec also.

Have you ever heard of the flywheel key breaking? Could it be possible that the flywheel has slipped? Internal timing I can't imagine would skip a tooth.

It is a starter generator engine, so if the key did break its wedged in good enough to let me turn the motor over with the starter. So probably not a broken key I guess.

 

[MH81]

Flywheel keys shear all the time.
Also check the kill wire isn't grounding.

 

[bowtiebuster]

Thanks! I will check the key tomorrow. Also eliminated all wiring from the equation so it is surely not grounding there. I appreciate the input and will let you know what I find tomorrow.

 

[robert_p43]

That appears correct to me, thinking back to when I got my Sears HH100 running. I have a friend that wasn't getting spark and he had made a metal clip where the pounts wire, kill wire, and condenser wire all clip tigether. The old clip was some kind of plastic. The metal clip just grounded everything out.

 

[KC9KAS]

I have a HH70 that keeps sheering the key, so yes, sheering is NOT Un-heard of!

 

[ckjakline]

Also double check your plug gap.I had a brain fart and set dads to .035" same as a small block chevy.I would get intermittent spark and it wouldn't run.Spark plug gap is also .020'.That will also effect timing.I think that when I set his coil gap I used 2 feller gages.One for each side.

 

[bowtiebuster]

Hey guys and MH81,

I removed the flywheel yesterday and found no problem with the key, much to my disappointment. So that's not the problem. I'm wondering if it's my coil again. These things are such a pain, I never had any problems like this with my Kohler K241. Maybe I should yank the HH100 and throw in a 10hp china diesel or a honda clone and forget about it.

 

[MH81]

If you have a points unit, It is an easy deal to retro fit to a coil instead of the magneto. Gotta change the switch (from magneto kill to Ignition [automotive]power) and a little rewiring.

 

[bowtiebuster]

Thats an idea MH81, but I'm on the fence about shelling out the cash for an automotive coil, coil wire, condensor and ignition switch. Is the HH100 really worth the trouble?

 

[MH81]

Thats an idea MH81, but I'm on the fence about shelling out the cash for an automotive coil, coil wire, condensor and ignition switch. Is the HH100 really worth the trouble?

I would say yes, as long as its in good, serviceable condition.
They are very strong engines. Ryan's with the points is a workhorse... Great torque.
Here is The engine blowing snow. And at this point we hadn't even determined the points werent gapped right. It's got more power now, we just haven't had enough snow yet to really test it.

 

[bowtiebuster]

Thanks MH81, I will give it a try. I think before I purchase anything I will borrow the coil and wire from my Mustang to verify that it's a good runner. I will post up the results when I get around to spending some time in the garage. It's -2 celsius here and dropping to -5 ( 23 f ), and my garage isn't insultated or heated so getting the motivation these days is difficult. lol

Thanks again

 

[MH81]

Thanks MH81, I will give it a try. I think before I purchase anything I will borrow the coil and wire from my Mustang to verify that it's a good runner. I will post up the results when I get around to spending some time in the garage. It's -2 celsius here and dropping to -5 ( 23 f ), and my garage isn't insultated or heated so getting the motivation these days is difficult. lol
Thanks again

Please do keep us up to speed. Would love to see pics of the progress.

I hear you on the cold. This winter has stiffened up my hands more than I want to admit.