Brand New Honda Mower Runs Lean

[RCBS]

I think the main jet is doing fine. It's the idle jet that's being too restrictive. Once the blades start whirling, the engine runs fine. I assume it's running off the main jet with the engine under load and with the blades engaged.

Check the little black vent with a piece of wire on your wire brush also...the cleaners don't go small enough.

 

[Wonkydonkey]

I will leave these here (pics).

I know a few hrs is short to gather a vid of the mower running. Cutting and running @ full Revs and standing still.
As I said before, I think it’s the automatic throttle control (load no load thing) ie engine governing device.

Btw. That's why. I like vids

However I will leave my chief apprentice (@LAWN BOY )to help you with any more questions .
if he can’t answer your questions ? I guess you could trash it and buy a battery thing As cancerfornia wants everyone to get a bettery everything

 

[bogieboy]

I have a feeling that if I bought a brand new Genuine Honda carburetor for a $100 it would come with the same exact idle jet that's too small.

What is a dental bit?

Yes I bought the mower at the big box store because it's one of the few credit cards I have left.

Dental bits are tiny flexible (usually tapered as well) drill bits, usually used for root canal work... honda main jet included for scale...

 

[bogieboy]

I think the main jet is doing fine. It's the idle jet that's being too restrictive. Once the blades start whirling, the engine runs fine. I assume it's running off the main jet with the engine under load and with the blades engaged.

I agree, it is either a pilot jet issue, or a slight airleak from a missing/improperly installed/torn gasket

 

[EFSM]

I agree, it is either a pilot jet issue, or a slight airleak from a missing/improperly installed/torn gasket

Agreed. Sounds like a piece of manufacturing dirt in their insanely small idle circuit jet. And their intake gaskets are frustrating to all get in position while installing the carburetor and filter housing.

 

[Loony661]

I think you’re overthinking and creating a problem that isn’t really a problem. It starts easy, and runs without skipping a beat when you engage the blades. It’s likely just not up to operating temp when the choke shuts itself off. That, and the EPA has these little engines on the edge of lean all the time.

 

[Merkava_4]

Agreed. Sounds like a piece of manufacturing dirt in their insanely small idle circuit jet. And their intake gaskets are frustrating to all get in position while installing the carburetor and filter housing.

They fixed that by going with threaded cylinder studs. It's actually quite easy now.

 

[EFSM]

They fixed that by going with threaded cylinder studs. It's actually quite easy now.

That's extremely great news!!

 

[FergusonTO35]

You can buy really tiny cobalt drill bits in thousandth of an inch sizes, with a large shank for a regular drill chuck. I bought some to enlarge the jet on a B&S OHV push mower engine, I think it was .015 or something like that. You aren't going to find them at the hardware store as they are used in specialty manufacturing, I got mine on Fleabay.

 

[r7000]

Okay dude…I assumed it was under warranty.

If you’re so fukkin great why are you here asking for help??

 

[r7000]

fwiw when i bought my hrx way back in 2005, i bought a spare carb for $15 for it at the time, not a genuine honda carb, but you don't need a genuine honda carb, i like using boats.net and go under honda marine and you will see mowers and can navigate to your specific model. Then get that honda part number for yours, and then google that carb part number and find economical replacements.

true the small engine market has been corrupted with climate/emissions bs. so they make everything lean and it's on the ragged edge with no adjust ability - is yours a case where the carb jets are simply not big enough, i sort of doubt it. pulling the emulsion tube thing that sits vertically above the main jet clean that real well in addition to the unscrewable main jet. you don't need a drill bit you likely won't find one small enough I forget what size but u just need something that will fit the main jet hole and that you can work in and out to scrape. it's brass, so any kind of steel wire will work.

the other thing is to simply raise the float level in the carb, which will result in an all around richer mixture, so bend the tab on the float just a tiny bit and keep retrying until your lean condition resolves, I bet that's all that's needed.

 

[r7000]

If it’s brand new why are you working on it vs a certified Honda mechanic?

for work when i brought a brand new nortstar generator with a honda engine to a local place for an ignition coil replacement - obvious, it failed 5 minutes after 1st start, it sat there for 3 months with no eta for "warranty repair". worst experience ever, i kicked other ppl's *s-word out of the way when I went back to take my gen back, if you don't specifically buy it from them then warranty repair and certified mechanic bla bla is all a big facade.

I amazon'd a new coil for $70 out of pocket, installed it, been fine the last 10 years.

 

[bogieboy]

for work when i brought a brand new nortstar generator with a honda engine to a local place for an ignition coil replacement - obvious, it failed 5 minutes after 1st start, it sat there for 3 months with no eta for "warranty repair". worst experience ever, i kicked other ppl's *s-word out of the way when I went back to take my gen back, if you don't specifically buy it from them then warranty repair and certified mechanic bla bla is all a big facade.

I amazon'd a new coil for $70 out of pocket, installed it, been fine the last 10 years.

That dealer sucks... as a honda dealer mechanic... i dont care where you bought it, i stand behind the honda warranty... and, if you didnt register it when you bought it else where, i will even register it for you so you have full warranty coverage... not all dealers treat customers like crap... some of us actually care....