I have a GX690 with a 10gpm belt drive pump. It ran all day without any problems, then when I got to my last job it would start pulsating and die. The longest I got it to run was about 20 seconds before it died. This motor only has 49 hours on it. I checked the oil level and it was fine. I noticed a deposit in the fuel filter so I replaced it but there was no difference in the way it ran. Any ideas? Im not the greatest small engines guy. I was thinking cleaning out the carb but didn’t want to dig that much into it if I didn’t need to.
Are you sure it’s the engine? It might be the unloader.
If it’s the engine check for spark and fuel. If you don’t have a spark tester you can get one at any auto parts store. Check to make sure the fuel pump is putting out a decent flow. Unhook the fuel hose from the carb, start the engine, and see what the stream of fuel looks like coming out of the hose. You sometimes have to rig up a little bottle of fuel to gravity feel the engine while testing but there’s usually enough fuel left in the carb to run for a minute or two. Or, just buy a new fuel pump and throw it on. If that’s not it at least you’ll have a backup.
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I disconnected the whip line between the pump and my pressure hose and let it just spray straight from the pump so there was no possibility of any back pressure. It still did the same thing. Would disconnecting the whip line take any unloader issue out of the picture?
Sounds like fuel delivery. Most common is going to be a clogged fuel filter. If that’s not it, pull the fuel screen from inside the metal tube that goes into the carb (see picture) and clean it. If that’s not it, pull the carburetor and clean it. If THAT’S not it, grab a replacement fuel pump and stick it on there. These are incredibly common engines, chances are you can pick up a new carb or fuel pump from a lawn equipment store near you
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I cleaned out the screen and it ran for maybe 20 seconds then died. I started pulling out the carb but it started down pouring so I quickly slapped everything back together and will have to try tomorrow. I appreciate the info so far!
No worries. If you need help with the breakdown and cleaning of the carb, let me know. It’s truly not difficult except for keeping track of tiny parts, and keeping carb spray out of your eyes
@marinegrunt had a good point too, about the fuel pump. It’s worth the 30 seconds of pulling that hose and cranking it to make sure you’re getting a decent stream
I will try pulling the line from the fuel pump first tomorrow. I was actually just searching google for a good walkthrough for removing and cleaning this carb. Any links would be helpful.
You can pull the line if you want but before you even do that take a screwdriver and tap on the fuel pump housing with the handle portion. TAP on it. Not bang on it. Three or four tippy taps and if it starts running like it should then you know your pump is on its way out.
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My replies keep getting formatted all weird when they post. Sending you a PM with a walkthrough
So, I have learned a lot along this journey. I tried tapping the fuel pump like @DisplacedTexan recommended to see if it would start to run the way it should but no dice. I finally took the carb apart with the help of a youtube tutorial and the awesome backing of @Jake_Lambert. I officially cleaned a carb for first time! The best part is there were ZERO “extra parts” when I put the carb back together! When I was half way through, it dawned on me that the float bowl was empty when I took it apart. So im assuming where the fuel entered the carb was clogged. I am waiting till tomorrow to get some fresh fuel and even changing out my gas tank just incase. If that doesn’t work, ill replace the fuel pump. And let everyone know how it goes.
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I bet the fuel pump is bad.
Well, it can’t always be that easy but at least you tried and now you can focus on finding the true culprit. Good luck with it.
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If that doesn’t fix it disconnect your oil low sensor. You said you checked the oil but it sounds like the oil sensor is shutting it off.
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I forgot to mention the most important lesson I learned. When starting the engine with the front cover off, keep your hands out of the way of the flywheel. Took off a layer or 2 of skin on my wrist. Oops!
Bill has a good point there. I don’t think I’ve ever had a low oil sensor go bad on me but it certainly could be that. Worth a shot.
So I bought a new gas tank, line, and filter and put some new gas in the tank. It would turn over and over but nothing would happen. So I took the plastics off to make sure I had everything connected. Sure enough, I didn’t have the electrical cable plugged into the fuel cut solenoid. Plugged that in and put the plastics back on and she started right away! I let her run for a few minutes and everything was good. I’m going to connect my hose to refill my buffer tank and let it run some more just to make sure it will stay running. I am currently a happy camper!
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I’ve had 2 go bad. Lol
Well, I ran it for about 10 minutes without any pressure lines on it so the water was just spraying out of the pump. The engine seemed quieter so i decided to hook up my pressure line and make sure im still getting the flow i am supposed to be getting (10gpm). I didnt do a bucket test by my guess is i am only getting about 5gpm. Then once I let off the trigger, the engine died. It isnt triggering the unloader. It did it once but the rpms took a dive when it did it. Now I will begin my research on that.
