No Fire To Spark Plug 149 Cub Cadet
 

Had all the bolt on parts off engine and pulled engine to pull oil pan. Was having trouble with the tab on the cam shaft that opens exhaust valve before firing. Tab broke off. Retrieved tab from engine that had broken off and put oil pan back on. Put engine back in frame and put everything back on that I had taken off. Put oil back in and tried to start engine. Would not start. No fire to the spark plug. Checked wiring on coil and had black wire from ign. on pos. side of coil. Wire from points and condenser wire are on the neg. side of coil. Got my cheap Harbor Frt. digital meter out to start checking the coil. Set meter to 200 ohm setting and got a reading of 4.2 ohms from pos. to neg. on coil. No reading from pos. or neg. to ground. Set meter to 20k ohms to check plus to tower. Got a reading of 7.4. Do not know if this means 7.4k or just 7.4 ohms. Reset timing using static method and a test light. Took a compression test and it read 98lbs. compression. Don't know what it should read. Leaked down about 2lbs. in about 5 min. Not sure you can do a leak down test with this gauge. All this and still will not fire. Getting fuel to carb. Had fuel on spark plug when I removed it. Sorry for the long post. All help appreciated. Have a great day.
Bob

Resistance should be approx. 11,500 ohms. I'd say you have a bad coil. Do you have another Kohler K engine you can swap one out of?

Wow, lots of things changed during that operation.

If you lay the spark plug on the head so that the flats of the plug are resting against the (grounded) cylinder head and crank the engine, do you see any spark ? (do this in a dark area , obviously). You should be able to see it and hear it.

Were you making those measurements with the coil connected?

I'd try and swap a coil (as mentioned above) too. Barring that, it's probably something you changed not a coil mysteriously going bad , even though that's possible.

I'd consider putting the ohmmeter on one side of the points and turn the engine over by hand with the other side of the ohmmeter on the points side of the coil wire. Do you "see" the points open and close? Is the condenser on the correct side (the points side) of the coil (this shouldn't make it fail, but best to check).

Is the + side of the coil @12 v when the key is on?


Summary: First determine if it's getting any spark at all. If no, we'll backtrack. There's only a couple things it could be.

Hook your test light to ground. Probe the negative terminal (points terminal) on the coil and crank the engine. Test light should flash. If not, file the points and check to make sure the wire from points to the coil is not grounding out somewhere. Common area is st the point cover.

If it flashes, check the coil tower terminal for corrosion. Replace the coil wire and spark plug as necessary.

Hard to believe a coil failed just sitting. Highly unlikely.

I think pos to neg terminals on the coil should register about 4-5 ohms. I think the coil is fine.

Like J-Mech has said, it's probably the points. I would take a slightly different approach though, being basically lazy.

Step one, clean the points. Using a small strip of sandpaper and draw it between the contacts to clean them. Try for a spark again. I've found that's usually all it takes.

If that fails, follow J-Mech's method.

I got one of these at the Chinese Freight store for about five bucks. Comes in quite handy in situations like this.

That looks like a decent buy for that price. Next time I'm in China Freight I'll snag one.

I guess one other thing for the OP:


Are you sure the spark plug cable is making good connection and is firmly seated at both ends (and clean).

Went to the garage and rechecked the things that you all said to check. Thanks for all the help. Still not running. I do have a strong spark at the plug. Tested it by putting the plug close to a ground with low light and had a good spark. Yesterday I tested it by putting a screw driver in the plug wire and putting it close to a ground. Had not turned off the lights and could not see a spark. No corrosion in the coil or my new spark plug wire. With the ign. on, I get 12.4 volts to the pos. terminal of the coil. Hooked my test light to neg. terminal of battery and cranked engine. Put test light to screw that wire hooks to to go to coil. Light flashed on and off while cranking. Removed spark plug and had fuel on plug. Cranked engine over and fuel squirted out the spark plug hole. Before I did that I took the fuel bowl off to make sure the needle valve was not stuck in it's seat. It was not. Could I have knocked a wire loose under the dash while hooking up the choke? I looked as best I could and could not see a loose wire. This engine was running before I pulled it . Any other advise? Thanks again to all that responded . Great Forum, Great people with a lot of knowledge about Cub Cadets. Have a great day.
Bob

If it's got spark and if it's got gas, we're left with compression and timing. I'd double check timing since you mention that you've re-set it.

Does it sputter or try to start at all?

Well, you said you have 12V at the coil. Not sure what wire you think you may have knocked off, but if you have power to the coil, that's all you need. If there was a wire knocked off, it would have to be something non ignition related that wouldn't affect running.... So, no. You don't have a wiring issue.

You have spark, you are apparently getting fuel. Either too much fuel, or you flooded it.

If the needle valve is sticking, or not shutting off, then you should have gas running out the carb. Like dripping/running. Should be pretty obvious.


Only a couple possibilities left:
*The fuel is bad. (You don't say anywhere how long ago it was running.)
*You flooded it and just need to pull the plug out, crank the engine to dry the cylinder some. (If you do that make sure the spark plug wire is far away from the spark plug hole, and also not near the carb. Might have fire where you don't want it.)
*Timing is not correctly set
*Something you took apart didn't get installed correctly.

Couple things I want to point out that makes me somewhat skeptical:
You stated in post 1 that you took the engine apart to retrieve a broken ACR tab. You do not say you fixed or replaced the cam. I find it surprising that your starter can crank the engine if the ACR is not working. 14hp is big motor.
Second, you stated that you had 98lbs compression. If the ACR was working, you shouldn't have that much, AND that's pretty high compression for that starter. If this engine cranks, I'm skeptical of that number.
Third, you stated you did a leak down test, but you don't know if the gauge you are using is capable of that test..... um, well, do you know how to perform a leak down test? A regular compression gauge will not do one, so just how exactly did you perform that test?? Takes a leak down test kit to do one, and it should have two gauges on it. So.... skeptical about both your compression test and the leak down test.

Alright... so does this engine have compression? If so, how much? What all did you take off of it? You say you had all the bolt on part off of it? Head? Did you remove the head?

Until we know if what you did to repair the broken ACR, kind of hard to say what the problem is. It has fuel, it has spark. I feel confident it's getting air...... should run.