18hp opposed twin no spark and turns over hard

Brett.m

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I posted a little bit ago with a wiring problem that I believe I have figured out, but now I have a no spark and I believe too high of a compression problem. It is a 422707-1214-01. I put this engine in to replace my old one that threw a rod and the guy I bought it from said it has been sitting for about 2 years. I know the battery I have on may be too weak to start it, but I have also tried jumping it with my truck and a battery charger with engine start option. It doesn't even get one turn before it stops. However, it will continuously crank if I take the plugs out, leading me to believe there is too much compression. From everything I have read on the internet, it looks like my valves need to be adjusted and I'm not sure if I'm up to that process myself. Depending on what you guys think it is, I may just bring it to an actual small engine mechanic. My other problem, is I tried checking the spark while I had the plugs out, with the wire hooked to it, touched the bottom of the plugs to some metal on the engine and no spark. The ignition coil and plugs are all new, I gapped the armature with a folded piece of paper, and took all the rust off of the flywheel. Any input?
 

ILENGINE

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the valve clearance were not a normal problem on the opposed twins. doing the valves on the L head is a major mechanical repair. First make sure you don't have 12v going to the ground wire coming off the ignition module, or if you do the new module is most likely now toast. also try checking for spark with the wire disconnected from the module. If you have spark then, the problem is in the tractor.

The opposed twins are hard on starters. Not enough oomph for what it has to turn over. You may have a faulty starter problem, which will require replacing the starter.
 

Brett.m

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I suppose replacing the starter wouldn't be a bad idea. I was just hoping to not put the money into a new battery and starter and have it still not turn over. I guess in the end, it'll need it anyway so I'll try that.

Still not sure about the spark though, as I am confident there is no voltage getting to it. That's why there is a new one in the first place. What I did after I toasted the original is ran the wire to a switch I had and ran another wire from the other post on the switch to a ground to make a kill switch because I wasn't sure what else to do with the wire. Thanks for the reply.
 

Brett.m

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Just for the heck of it, I tried what you said about disconnecting the entire wire from the ignition module and I got spark. I still am not sure why that happened because like I said, I had the wire going to a switch and to ground from the switch. Can I just leave that wire off and not use a kill switch? The original engine did not have a wire coming off the ignition modules. I am however pretty confident the starter needs to be replaced, it makes all kinds of noise when I try to turn it over with the key. So in the meantime, I'm going to buy a battery with at least 300 cca.
 

Phil G

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Just for the heck of it, I tried what you said about disconnecting the entire wire from the ignition module and I got spark. I still am not sure why that happened because like I said, I had the wire going to a switch and to ground from the switch. Can I just leave that wire off and not use a kill switch? The original engine did not have a wire coming off the ignition modules. I am however pretty confident the starter needs to be replaced, it makes all kinds of noise when I try to turn it over with the key. So in the meantime, I'm going to buy a battery with at least 300 cca.

Could the wire you removed go to an interlock switch? Seat, clutch, blade engagement.

I'm not sure about your engine but, some of these engines used a nylon gear pinion when an aluminium ring gear was fitted, could just be the pinion is damaged.

Good luck, Phil :smile:
 

Brett.m

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It was just the wire from the module going to a single toggle switch I had laying around, then another wire from the switch grounded on a bolt on the engine. But I figured out why I got no spark with the ignition module wire connected, is because I also had another wire grounded in the same spot, which I thought was a ground, but after looking a wiring diagram up (because I don't have the manual), was actually a wire from the engine that is supposed to go to the headlights. So it was getting voltage.

Thanks for the reply. I'll post the results when the new starter comes in and I get a brand new battery on there.
 

Brett.m

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UPDATE: I got the new starter, bought a new starter solenoid, and a 360 cca battery. Turned over as if there was no resistance at all and started right up. Thanks for the input fellas.
 

Rus A

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I posted a little bit ago with a wiring problem that I believe I have figured out, but now I have a no spark and I believe too high of a compression problem. It is a 422707-1214-01. I put this engine in to replace my old one that threw a rod and the guy I bought it from said it has been sitting for about 2 years. I know the battery I have on may be too weak to start it, but I have also tried jumping it with my truck and a battery charger with engine start option. It doesn't even get one turn before it stops. However, it will continuously crank if I take the plugs out, leading me to believe there is too much compression. From everything I have read on the internet, it looks like my valves need to be adjusted and I'm not sure if I'm up to that process myself. Depending on what you guys think it is, I may just bring it to an actual small engine mechanic. My other problem, is I tried checking the spark while I had the plugs out, with the wire hooked to it, touched the bottom of the plugs to some metal on the engine and no spark. The ignition coil and plugs are all new, I gapped the armature with a folded piece of paper, and took all the rust off of the flywheel. Any input?

What brand engine is this? Kohler, Briggs, Kawasaki? I need answers about a Kohler Magnum 18 opposed twin
 

bertsmobile1

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Rus
:welcome:

In his first post Brett gave us the most important piece of information , the complete engine number 422707-1214-01 which identifies the engine as a Briggs .
All the information given to him applies equally to your Kohler.
Please start a new thread in the Kohler section of the engine repairs https://www.lawnmowerforum.com/forumdisplay.php/62-Kohler-Engine-Forum
There is only 1 forum it just makes things easier to find and makes searching for answers like you have done easier,
Good to see you have taken the time to introduce yourself.
Name your thread " magnum ( engine number ) has no spark.
There were a lot of Kohler opposed twins in 2 different series , K 428 to K 662 & KT 17 to KT 21.
To answer the question about the firing posted in your introduction post .
If there is no distributor on a magneto powered engine, every time the magnets pass the coils a spark is generated.
Rust , paint, grease on the flywheel or coil posts make zero difference to the spark unless there is so much that the magnets touch when they pass the coils or the surface under to coils where the coils mount are too rusty to make a circuit.
 

Tinkerer200

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"but after looking a wiring diagram up (because I don't have the manual), was actually a wire from the engine that is supposed to go to the headlights. So it was getting voltage."


Welcome and glad you got your engine running. For future reference, I can send you a Service Manual for your engine IF you like. Address below, put in proper format and remind me engine model number and what you want.

Walt Conner
wconner5 at frontier dot com
 
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