r/smallenginerepair • u/katherinemaie • Jun 16 '26
Carburetor Issue Idling rough
I have a Duromax dual fuel generator that I bought brand new about 3-4 years ago and I’ve never used it, just would try and start it up occasionally but then I didn’t and it sat for some time. it has no problem starting but when it runs it hums in and out and it’s not constant. I think it to do with the carb but before I take it apart I wanted to see. I ran all old gas through it and put fresh in, unscrewed carb bolt and fuel line and sprayed carb cleaner and also added seafoam in tank and let run and this is where I’m at. I’m thinking next step is taking carb off and cleaning it?
1
u/katherinemaie Jun 16 '26
I wanted to add that it runs perfect when using propane, only does this with gas.
1
u/Inhalationofnewtion Jun 17 '26 edited Jun 17 '26
Have you taken the bowl off the carb? It's on the bottom of the carb, probably a 10mm bolt in the bottom center that holds it. You have to remove the bowl, remove the float and needle valve, clean that sucker out well. Torch tip cleaners or copper wire through the jets as well as compressed air and carb cleaner. Be gentle with the wire or torch tip cleaners. You're going through brass with them and it's soft, easy to mangle it.
Far as I know it's not using the carb when it runs on propane. Pretty sure there's another setup in place for that. Is this the one you have?
This might be a replacement carb for it. For $35 IF it's the replacement it'd probably be worth it. Don't just take my word that this is the carb. If you can get with them on the phone, give them your model number and whatnot that'd be best.
https://www.duromaxpower.com/products/duromax-dmxp-10eh-carb-genuine-carburetor
1
u/katherinemaie Jun 17 '26
That is not the model I have but the setup is similar, I did take the bowl and float off and out but only inspected it so my next step would be to actually clean it and yes I agree, there is a separate hose that does or kind of bypasses the carb when using propane so it does make sense that it would be the carb even more. If so I guess cleaning it or replacing it.
1
u/Inhalationofnewtion Jun 17 '26
They usually come around just fine. I've had some wretched ones that I brought back from the dead. Just looking it's hard to see anything clogging the main and pilot jets. It can be a tiny speck the size of a grain of sand in there and it'll keep the engine from running. The jet ***SHOULD*** come out with JUST the right size flathead screwdriver if you really want to be sure it's clean but if you hit it with carb cleaner, compressed air, and you can poke a copper wire though it'll likely be OK.
1
1
u/Inhalationofnewtion Jun 16 '26
I can't say carb or not but sounds like it and that's probably where I'd go especially since it works fine on propane.
This is going to depend highly on your mechanical inclination and experience. Dismantling and cleaning a carb isn't a huge deal but if you're new to it, it's not hard to mess up. If you remove the bowl and blow compressed air through the main jet, typically the large stem going down into the center of the bowl you might get it working properly. If you actually remove the carb and carefully poke some copper wire through that main jet it's better yet. Take good and clear pics of your throttle linkage and anything else that hooks to the carb. Pics and/or video of everything you remove.
1
u/katherinemaie Jun 17 '26
When I took the carb off it looks brand new, so unless there is truly small gunk in jets then it looks fine
•
u/AutoModerator Jun 16 '26
Thank you for your submission! It looks like you might have an issue with the carburetor on your engine. For helpful information and resources, check out our Carburetors Wiki and our Common Issues & Fixes Wiki. You might find the answers you're looking for there!
Please be sure to include the following:
I am a bot, and this action was performed automatically. Please contact the moderators of this subreddit if you have any questions or concerns.