A few days ago, my engine stopped. Turned out it was low on oil. Topped off and was good to go. Fast forward to today and it stopped again. Again it was a little low but not much. It’s not smoking and no signs of a leak. Put a tad more in but the engine is bogging down when on the gun. I’m guessing the unloader is going bad? If I open my ball valve all the way, the engine seems to run fine (maybe a little sluggish). Belts might be a little loose but not sloppy.
Is it a GX390?
yes. Just spoke with Pressure Pro and they said it is an engine issue due to the engine bogging when on the gun.
How many hours on it? May be time to adjust the valves.
Keep in mind, Pressure Pro is clueless about mechanics. They just install parts to make a puzzle. My bet is the unloader first, coil second
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Oil doesn’t disappear on it’s own. It has to either leak out or get burned. I’d yank the spark plug out & have a gander at it. When you are on the gun, your engine is under more of a load than with the ball valve wide open. It needs more fuel & also creates higher compression levels in the combustion chamber, under which your rings expand. If the valves need adjusted, it will definitely affect performance but it will usually let you know when it tries to yank your arm off when you pull the rope. I kept a spare engine & a spare pump handy in my GX390 days but I can’t possibly tell you enough how much I love the GX630. It’s a massive upgrade.
Guessing around 500-600. Going to check the valves next.
Starts on first pull still. I just cleaned the carb. Bowl was fine. No water in the gas. No signs of sediment in the gas tank. Even with no load, the engine is running like it is choked off a little. Spark plug was a hair lean but not bad. Threw a new one in but no change.
I am planning on building a new trailer at the end of this season as I have been busier than ever and I don’t think I can get any faster on jobs than I already am…without a bigger unit. I am looking at the GX630. Seems a lot of guys like it.
I was really hoping it was the unloader but after running the engine again at home, I can tell it’s sluggish…even after checking the plug and cleaning the carb. I don’t know much about Pressure Pro but will take your word. The guy I spoke with made sense that under a load, the engine can’t keep up. I am pretty clueless but am trying to make sense of this. I’ll look into the coil.
You gotta read the old plug, it’s trying to talk to you… but upgrading the engine is not something you’ll regret. I cut my teeth with a GX390 at 4gpm & then went to a Predator 15.8 at 6.8gpm. It sped up everything but my surface cleaner, oddly. Predator crapped out quickly & a new GX630 showed up at my doorstep. My surface cleaner woke up after that & I can blaze through flatwork like crazy nowadays. Thanks to Mr William for jumping through hoops on his day off to help me figure out how to wire the darn rectifier box that came with it. I owe that man a keg of Cheerwine & a trip to IHop. It’s like a much fancier version of Waffle House.
Adjusted the valves. No change.
Get another engine & fix your old one when it’s convenient.
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I don’t remember what Honda recommends for intervals but at that many hours it’s worth a check. If it’s starting first pull I doubt it’s the valves though. I’d be leaning more toward a bad unloader.
Exhaust side didn’t look so good. Both valves needed adjusted but the engine is still running poorly even without a load on it. I’m wondering if the valve is burnt and not allowing proper seating? I’m also wondering if there’s an issue with the carb as without a load, it kind of runs like the choke is slightly on.
Probably a not going to be the problem but have you checked the air filter? A clogged air filter will cause an engine to run poorly like the choke is on
Yes, it was fine.
What color is the plug? Black is to rich, white is too lean, light brown to a tan is about right for fuel mixture in a gas engine. You have to look at the one you pulled out when you first had the problem. Oily mean you have bad rings. build up of black dry looking junk on the plug carbon build up. here is a link to how to read a spark plug,
https://www.championautoparts.com/Parts-Matter/automotive-repair-and-maintenance/how-to-read-spark-plugs.html
Geez that doesn’t look great. That gunk makes me think you’ve got either valve stem seal issues or maybe a broken ring.
Update: Tried finding a complete carb to swap out. Local guy searched around and sent me an hour away to a little shop in Amish country. I went there and the mechanic listened to the engine and said it might be the carb but he thought it could be a valve issue after showing him the picture. I jokingly asked the sales guy if they stocked that engine. “yeah, I think we do”. 
They actually had 2. One was the electric start so I opted for that. I know I could swap it out but asked how long it would be to get it. They said a week so I figured I’d just take it with me. Then the guy talks to the mechanic and he said he would do it right then. E-start wouldn’t fit as it was hitting the pump and there wasn’t any room to adjust the pump. 1 hr labor of $65 (can’t beat that) to get up and running with the piece of mind was well worth it. They are going to look into my old engine to see what it will take to fix it. I’ll update when I find out.
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God, I love it when stuff just works out like a dream. Too bad on the electric start though. That would’ve been nice and I plan to upgrade my 5.5 to electric start when I start having issues with it.
