GX390 runs too rich

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I have a 13hp Honda that is running too rich. It is brand new. I had to buy it out of town because the local Honda shop doesn't deal in them. Because they don't sell them they are saying they can't/won't perform any warranty work. Aren't small towns great?

The problem is, it runs so rich that I can't even put the air filter on. With the filter off it still runs so rich that the exhaust can be seen and burns your eyes. The jet adjustment did nothing to help out. Are altitude is only 2900 ft.
Any ideas would be very appreciated.

Thank you
 
A Honda shop that doesn't sell Hondas? What are they selling, motorcycles?


Anywho...off to your problem. Dumb question, but is the choke open fully? How does it feel when you pull the rope...hard to pull, too easy to pull? You haven't got the engine overloaded have you?

If it's none of the above, maybe a main jet swap is in order.
 
They consider themselves only a MC shop.

Choke is open, at least to the limits of the lever. Starts just fine, not to hard too pull. I have had these before bit this is the first with a problem. Runs bad/rich with no load on engine at all. I have to have the air filter off to lean it out enough to run better, but still runs rich.
The jet on the side of carb had no effect on the engines performance. Is it possible it wasn't set right to start with? It only lets you turn it about 1/4 of a turn before you hit the stops.
 
Thank you for the quick help. Looks like I will have to pursue Honda warranty a bit more, see if they will authorize a repair through another small engine shop.
If not I guess i will remove the carb and go from there.

Thanks again.
 
I am thru with Honda , Mine threw a rod , My buddys messed up .. Then I went and Bought a Robin Motor and it ran great for about 1 week and it is messing up... I think I am going to go and buy a Kohler from a local dealer and be done with it... Small Engines these days are all made from cheap cast and aluminum... Whatever hapened to the old Wisconsin motors .. I have one on a lawnmower thats probably 30 years old and it runs great..
 
From what I've heard, Honda small engines 18+ hp are not that great, but the smaller ones are great and I know my 13hp Honda has been fine. When I need another engine that's 18+ hp I'll almost certainly purchase a Kohler as I've not heard anything bad about them.
 
Make sure that the choke flap in the throat of carb is moving when you adjust the choke control. also if the local shop near you advertises Authorized Honda Dealer they are not allowed to refuse work on a Honda product under warranty if I were you I would go in to that shop demand to see the owner and if they still say no ask them for there Honda reps name and number or ask for corporate number, guarantee if you call them they will be fixing it. Down side is if they are forced to repair it you will not be getting there best service.dh
 
You didn't mention at what throttle settings it runs rich. The idle jet controls up to about 25% throttle. The needle up to about 60-70% the main jet size really matters at 70% to 100% throttle. Each jet has overlapping function. If it seems to run rich through out the entire range you must have a restriction such a bad choke or packing crap in the intake etc. At least it's rich. Lean could burn a hole in a piston pretty fast.

I know you guys will think I'm nuts but I run Chinese 13HP and 16HP Power Max (Honda Knock Offs) I buy from a guy in CA. Electric start $350 delivered to my door in 4 days. The only reason I bought them was I know a guy that runs at least 10 all the time and he hasn't had any major issues over the past year. He keeps spares on a shelf and if one dies he'll just swap it out in 30 minutes. He abuses the crap out of them. Never changes the oil etc. Warranty could be a problem I'm sure since the importer has to authorize a local shop to fix. But you can throw a couple away for the price of a Honda.
 
Ended up being a plugged pilot jet. Very small hole in the bottom of the black plastic jet. At least the Honda shop showed me where ti was, I wouldn't have guessed it was a plastic push in jet.
 
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