My Tractor Forum banner

1 - 15 of 15 Posts

·
Registered
Joined
·
6 Posts
Discussion Starter #1
Last night my Lawn boy let me down for the first time in 27 years. A week ago while cutting the grass, the engine did not seem like it was running to full potential. (Say 90% power). Last night I started it and it sounded like not full power again. I cut about 2 feet and it died and would not re-start. I changed the spark plug, drained the gas and bought new gas, but still nothing. I looked to see if I had a spark by pulling the plug and pressing it against the block, but didn't look like I was getting a spark. Could this be a problem with the ignition coil? Does the model even have anything as such? It's not electric start and has no self-propelled. Just an on/off switch. Can I bypass the on/off switch to see if the switch has gone bad? I sure dont want to lay my old friend down after such a long relationship. Any thoughts would be appreciated.
 

·
Lawn-Boy fan
Joined
·
1,566 Posts
This model has a CDI pack, which if bad would run $20-30 to replace. It isn't a hard repair at all. Take the shroud off the mower, and you can ground the coil, try starting and see if there is spark. Try it not grounded as well. I can't remember what year they switched from ground to run to open to run.

If you do have spark, there is a chance you may have plugged exhaust ports which also isn't very hard to remedy. Just have to pull the blade and muffler to check that out.

You have a great mower, it is sure worth fixing. Welcome to MTF!

Bob
 

·
Registered
Joined
·
6 Posts
Discussion Starter #3
Thanks for the reply Bob,
Could you shed some light on how to ground the coil? and I appreciate your kind words of saying its a great mower. I'd be lost without it.

Thanks,
Trent
 

·
Registered
Joined
·
6 Posts
Discussion Starter #7
Okay all...
I took wire off the cd ignition module (the ground I think with the wire connector) and added a wire to the module and touched it to the motor and also pulled the pug out, inserted it into the boot and touched it to the motor. pulled the cord a few times and saw no spack in the plug. Does this mean the CD ignition module is bad? I 'm not sure if I want to spend the $60-$80 for a new cd module if I'm unsure if it is the cause. Any thoughts?
 

·
Registered
Joined
·
2,420 Posts
Okay all...
I took wire off the cd ignition module (the ground I think with the wire connector) and added a wire to the module and touched it to the motor and also pulled the pug out, inserted it into the boot and touched it to the motor. pulled the cord a few times and saw no spack in the plug. Does this mean the CD ignition module is bad? I 'm not sure if I want to spend the $60-$80 for a new cd module if I'm unsure if it is the cause. Any thoughts?
CDI is bad. You can get one from around $20-$30. Ebay has them as well as other vendors www.mowpart.com and www.rcpw.com but check ebay first.
 

·
Registered
Joined
·
451 Posts
To make sure your CD pack is the problem, first remove it, clean the mounting surfaces on both the CD and the bracket. Also clean the flywheel magnet and CD laminations. Then regap it with a .010 shim. Verify that the switch and the connections are good. Then test for spark. If you still do not get a spark, replace the CD pack.
 

·
Registered
Joined
·
2,534 Posts
To make sure your CD pack is the problem, first remove it, clean the mounting surfaces on both the CD and the bracket. Also clean the flywheel magnet and CD laminations. Then regap it with a .010 shim. Verify that the switch and the connections are good. Then test for spark. If you still do not get a spark, replace the CD pack.
As above. Many no spark problems are just dirty or rusty connections. Clean them up first. I got my 7268 cheap because the PO put a open to run 683080 coil on it and didn't know the difference. I have to start it in the "off" position. Good deal for me.
 

·
Registered
Joined
·
373 Posts
Check muffler/exhaust ports first.
Ditto. I had one recently that smoked like the dickens and ran poorly at best. It finally dawned on me to check the ports, and while they were spotless clean, the muffler itself was caked full of carbon. I scraped/prodded/blew it out as much as I could, and it was better but still not perfect. I mowed with it anyways, and while running, all of a sudden it sounded all choked up and really quiet, then it let loose and started to run like a new mower! Must have blown the last bits of carbon out of the muffler finally. The excessive smoke cleared up almost instantly at that time too.
It hasn't acted up since.
 

·
Lawnboy Green
Joined
·
633 Posts
Hi T,
Dont give up on the old boy!

1978-1982 Lawnboy F engine uses an ignition that must be grounded to run (spark). With the shroud and switch removed and disconnected you wont get a spark. Make a jumper wire out of a small piece of wire and jumper the two tabs on the cdi where the switch leads have been unplugged from. CDI stands for capacitor discharge ignition. It is a self contained system which cannot be serviced. It either works or it doesnt.

1983 and later engines use an OPEN to run CDI, and these will produce a spark at the plug when the wires are disconnected.

The 1978-1982 CDI pack is usually white or light green. The 83 and later are black. Newer and aftermarket CDI's can be either color if yours had been changed at some point. The cdi is held to a bracket by two 5/16 head screws. Remove the screws and off it comes. Use a standard business card (.010-.015) to set the air gap between the poles of the CDI and the flywheel magnets. Sometimes these bolts will vibrate out which will allow the air gap to close. The gap is necessary for the system to operate.

If you have never cleaned out the engine's exhaust ports, my thinking is this is where your going to find your problem. Because a two cycle engine has no valves, a small amount of fresh intake charge spills out into the exhaust port before the piston can trap it and burn it. Because this fresh charge has fuel in it, the fuel sticks to the hot metal and burns. This will eventually fill the port with a charcoal like material preventing fuel and air from moving through the engine.

Its not a difficult job, but its dirty. Find a nice shade tree to work under and get someone to work as a go-fer when you need a wrench. Keep some good rags on hand.

-Remove the spark plug and set the mower up on its side.

-Remove the nut and the blade. If it is real tight, use a block of wood to keep the blade from spinning. I believe the nut is 13/16 and use a breaker bar if you have one or a short section of pipe over your ratchet handle if you dont.

-Remove the blade holder which is tapered to the crank. A little penetrating oil and a few taps with a light hammer should loosen it.

-Remove the three 1/2 inch bolts that hold the muffler cover to the bottom of the engine's muffler plate. When you put these bolts back in, remember that your threading a steel bolt into an aluminum hole so dont strip them.

-Remove the muffler cover.

-Using a flashlight, look up into the cylinder through the exhaust port. If its full of carbon, use a stick or a plastic knife to scrape it out. Do Not use a screwdriver because it is very easy to scratch the cylinder or the piston. Use the recoil handle to turn the engine over while its up on its side. I rotate the piston to the bottom of its stroke. Take your time and clean out the carbon, same with the muffler cover as it may be plugged too. An overnight soak in a pan of kerosene should clean out the muffler cover. Following the outdoor overnight soak of the muffler cover, run a coat hanger in and out a few times to knock anything loose that is hanging on.. When Im done cleaning them out, I use a water hose to check the flow.

-Reverse the steps and put it back together. Clean out the carb, put a new spark plug and air filter in the old boy and he should be good for another 20 seasons!

If you have questions, please post them or send a PM.

This service manual may help: https://lookup3.toro.com/ttcGateway/acrobat/manuals/lball.html


Best wishes,
Bob
 

·
Registered
Joined
·
6 Posts
Discussion Starter #15
Hey All...
Thanks for all the support. Took the advice from "GTP" and found a new cd pack at mowpart.com for about $40 (including shipping). My local lawn parts dealers all wanted around $80. That was the problem. Plugged it right in and my baby fired right up! Seems to be running faster (or more rich) than before. Is that from more charge? or probably me cleaning all the ports and exhaust looking for the problem. Thanks again for all your support. In May, the mower turned 27 years old. Wonder if I can get another 27 years. Told my wife I was so excited to have it running again, I should treat the mower to a set of 4 new tires. :)
 
1 - 15 of 15 Posts
Top