tommyg 155 #1 Posted Saturday at 08:20 PM I don't know if you guys can help me with this as I've replaced my D180 engine with a Kohler Command Pro several years back. But here's what's going on if anyone knows anything about the Command Pro. At first I thought it might be the pulse type fuel pump so I replaced it with an electric low pressure pump. I'm getting plenty of fuel to the carb. I've got spark on both cylinders, but I can't verify how strong the spark is, only that my spark tester shows there is one. It just cranks and cranks. There are times is seems like it wants to start, but never quite gets there. I have better luck when it's warmer, but it's in the 40's today and I still can't get it to fire. I replaced the carb, just because I wanted to rule it out, but to no avail. I've tried starting fluid which had no effect. Right now, I'm leaning toward the magnito on the flywheel, but hesitate to check it further because I have to pull the whole engine out which is no picnic. Any thoughts? When it does start, (which is less and less frequent these days) it seems to run fine. I've ruled out valve clearance as these are hydraulic valves. Share this post Link to post Share on other sites
JoeM 9,582 #2 Posted Saturday at 09:12 PM Does the command pro have smart start? those will go bad and the timing will be way off. The service manual has the electrical section that has a lot of info. Share this post Link to post Share on other sites
tommyg 155 #3 Posted Saturday at 09:53 PM (edited) Are your referring to the Smart Spark? That's what the manual seems to reference. Edited Saturday at 09:57 PM by tommyg 1 Share this post Link to post Share on other sites
JoeM 9,582 #4 Posted Saturday at 11:07 PM (edited) Oh one thing is the anti back fire valve on the carb working right? 12v has to it and it shuts off the fuel to the main jet internally on the carb. Smart Spark yep, if your engine is equipped with it, there will be a square black box on the shroud near the right valve cover. If all is right, valves, compression >140 (excellent is 180-200), and you pull the engine to check the mags, a good idea is to eliminate the system. Install a standard magneto kit. Edited Saturday at 11:10 PM by JoeM Share this post Link to post Share on other sites
tommyg 155 #5 Posted yesterday at 12:31 AM 1 hour ago, JoeM said: Oh one thing is the anti back fire valve on the carb working right? 12v has to it and it shuts off the fuel to the main jet internally on the carb. Smart Spark yep, if your engine is equipped with it, there will be a square black box on the shroud near the right valve cover. If all is right, valves, compression >140 (excellent is 180-200), and you pull the engine to check the mags, a good idea is to eliminate the system. Install a standard magneto kit. The solenoid is working. And even if it wasn't, replacing the carb would have put a new one in it's place. I can hear it clicking when I turn the key. There's no doubt in my mind it's getting fuel. Infact, the plugs are wet when I pull them out. I just don't know why it's not firing after confirming I've got spark. What's with the "conversion kit"? I've got a 25 HP. What makes this different than what I have? What I see in the image appears to look exactly like what I have in there. Share this post Link to post Share on other sites
pfrederi 19,808 #6 Posted yesterday at 12:35 AM Get a B&S sparkplug tester. The cheap Harbor Freight type will flash but it isn't sparking. The B&S will confirm the strength Share this post Link to post Share on other sites
tommyg 155 #7 Posted yesterday at 01:35 AM 59 minutes ago, pfrederi said: Get a B&S sparkplug tester. The cheap Harbor Freight type will flash but it isn't sparking. The B&S will confirm the strength Yeah, I was looking at those. I just spent $10 on one from AutoZone. It flashes, but like you said, it doesn't tell me how strong the spark is. Share this post Link to post Share on other sites
JoeM 9,582 #8 Posted yesterday at 04:09 AM couple things what model engine do you have and do you know what it came off of? you can check timing with a timing light. Have to bring the cylinder up on compression stroke Top Dead Center and mark the screen and housing. then start it up and note the timing advance, it should be firing before the line the one in the pic is a bad coil / unit and is bad, it was hard to start too. you can check the spark with your tester but have to look close best tested if you can get r running. weak spark vid good spark 1 Share this post Link to post Share on other sites
tommyg 155 #9 Posted 16 hours ago Thanks for those video clips. Big difference between weak and normal spark! I actually got it running this afternoon. After cranking for several minutes it finally "engaged". Ran great once it was running. How would you get it running with the tester installed? Would you connect it after it fired up? The engine is a Kohler Command Pro CH25S. Displacement 720cc. It was used when I bought it. Supposedly came off of some sort of floor cleaning machine, but I have no clue otherwise. Didn't have this problem at first. Kind of developed slowly. Share this post Link to post Share on other sites
tommyg 155 #10 Posted 16 hours ago Joe, here's a video of cylinders one and two. You think there's a bit more of an irregular spark on my vs the video you shared? Both appear to exhibit similar behavior. Share this post Link to post Share on other sites
JoeM 9,582 #11 Posted 4 hours ago (edited) 11 hours ago, tommyg said: You think there's a bit more of an irregular spark on my Yeah, it should be stronger than what is shown. Might have to dive in. Have you checked the compression, wondering what it is? just trying to get a fill for how the general condition of the motor. chart of coil numbers used if needed Edited 4 hours ago by JoeM Share this post Link to post Share on other sites
