Lo boy 154 died; no spark

[Keith Seymore]

Gentlemen –

I must start with an apology; I feel like a “bad relative” – you only hear from me when things are not going well….

Anyway – I did some searching but wanted to start a new thread because there may be some uniqueness in the way my tractor is wired up.

Last Sunday I was mowing along contentedly when the tractor just shut off – just like you had turned the key off.

Cranks strong but would not restart. Would not restart with starter fluid (not even a bark).

Towed it back around to the garage and began the diagnostic process.

It looks to me like no spark. I’m attaching a photo so you can see what I have here.



With the key “on” I have 12V at each of the locations shown by the red arrows. If I pull the coil wire from the distributor and place it near the stainless bolt (blue arrow - known good ground) I get no spark. The rotor goes around while cranking so I know the distributor is turning.

So – I bought and installed a new coil from our good friend Hamilton Bob and that didn’t seem to change anything.

Here are my questions:

a) What do you all think about that added resistor? Should that stay or should it go, since the coil is known to have an internal resistor?

b) The removed coil was marked “batt” and “dist”, whereas the new coil was marked “+” and “-“. I put the plus side to the white wire and the minus side to the distributor. Is this correct?



I’m thinking points and condenser next but am willing to entertain any suggestions you all might have.

Thanks in advance –

K

[Eugene]

The problem is internal to the distributor.

I would leave the resistor.

[Trent M]

I always connect the wire from the distributor to the terminal on the coil that matches the polarity of the battery ground. Negative ground battery, then distributor connects to '-' post on coil.

My guess is condenser is bad and might as well replace points too while you're at it, especially if its been a while.

[Larry B]

Sounds like the points are bad. An easy way to do a quick check is connect you meter to the terminal on the side of the distributor and ground and then crank the engine. The meter should swing from battery voltage to near zero volts rapidly as the points open and close. If you have meter with a needle this is easy to see. If you have a digital meter it may just just just show erratic numbers. A digital with a bargraph scale is handy here. If the voltage stays steady at around 9 to 10 volts while cranking then the points are not working. Usually the point spring breaks.
Hope this helps.
Larry

[Keith Seymore]

Update: pulled the distributor apart and found the flat spring which closes points broken. The moveable point is just hanging, never to be closed again.

Parts are on order; I'll make the installation after I get back from vacation.

K

[Denny Clayton]

Sounds like the points are bad. An easy way to do a quick check is connect you meter to the terminal on the side of the distributor and ground and then crank the engine. The meter should swing from battery voltage to near zero volts rapidly as the points open and close. If you have meter with a needle this is easy to see. If you have a digital meter it may just just just show erratic numbers. A digital with a bargraph scale is handy here. If the voltage stays steady at around 9 to 10 volts while cranking then the points are not working. Usually the point spring breaks.
Hope this helps.
Larry

Larry, welcome to the forum. I'm just up the road south of Sidney. Be sure to check out info for the Barnyard Bash the first weekend in June.

[Keith Seymore]

All set; back in business.

Replaced the points (which were pitted) and the points spring.

Purrs like a kitten now!

Thanks, everyone.

K