Honda Idle Jet Size

[Coupe]

Why do you want it to richen up at idle. They set there specs were it is
on the lean side and in a lot of countries that's what they want these days.
I have a Honda GSV 190 on my Grass Grub Mower and if you are wondering
what the mower is they were built in New Zealand for NZ conditions it just
starts like the normal older motors no surging but I can tell it's on the
rich side by the smell of it. If the filter gets dirty clean it cause they like plenty of
air and inless you have a reason why you want it richer as we have all said leave it
alone.

 

[Merkava_4]

Why do you want it to richen up at idle. They set there specs were it is
on the lean side and in a lot of countries that's what they want these days.
I have a Honda GSV 190 on my Grass Grub Mower and if you are wondering
what the mower is they were built in New Zealand for NZ conditions it just
starts like the normal older motors no surging but I can tell it's on the
rich side by the smell of it. I f the filter gets dirty clean it cause they like plenty of
air and inless you have a reason why you want it richer as we have all said leave it
alone.

I just want the engine to run smooth like it does on choke.

 

[bogieboy]

The guy at the mower shop says that hole below the Phillips screw is an air bleed. He told me if I really want to change the operation, I need to adjust the limiter cap so that it doesn't stop at the stop anymore. I'm surprised he would say that especially being the business owner. I told him he might get some black helicopters flying over his house for saying stuff like that.

If it were rich, yes... the screw controls how much air is flowing thru the pilot air bleed... you cant crank it down, as its lean already and you need air velocity to draw fuel from the pilot... but more air wont help.... the pilot jet needs to be enlarged... simple as that....

But what the hell do i know.... i only do about 30 carb rebuilds a month on hondas and other brands.....

 

[Merkava_4]

If it were rich, yes... the screw controls how much air is flowing thru the pilot air bleed... you cant crank it down, as its lean already and you need air velocity to draw fuel from the pilot... but more air wont help.... the pilot jet needs to be enlarged... simple as that....

But what the hell do i know.... i only do about 30 carb rebuilds a month on hondas and other brands.....

Which screw are you talking about? Are you saying the screw with the limiter cap on it is the air bleed?

That Phillips head screw is just a cap / cover for the mystery hole that we can't figure out what is.

 

[stretch5881]

Under your "mystery screw" is where the pilot jet is.

 

[bogieboy]

Which screw are you talking about? Are you saying the screw with the limiter cap on it is the air bleed?

That Phillips head screw is just a cap / cover for the mystery hole that we can't figure out what is.

This....

Under your "mystery screw" is where the pilot jet is.

Straight down under the screw, theres a small brass insert, that is your pilot jet, that is what needs to be reamed out ever so slightly.

 

[Coupe]

If you have not had the pilot jet out it is probably blocked. Take it out and
put your cleaner though it and make sure it is clean. As I said in one of
my other threads if you are going to ream it out be carefull how you go
about it. Just use the next size up and don't go big at the start. It's like
cutting timber if you take to much off you can't pull it back on.

 

[Wonkydonkey]

Gentlemen - you're not gonna believe this. I took the mower to three different professional mower shops today. They all said the mower runs perfectly normal for a Honda designed to meet California Emissions. They said as long as the engine doesn't surge while under load with the blade engaged, forget about it. They said I will never have to worry about fowling spark plugs.

So there you have it, there telling you are ocd,
And I’d agree because the lawnmower was still under warranty…

 

[Wonkydonkey]

I just want the engine to run smooth like it does on choke.

Then push it along so it’s under load
I don’t think you can have it both ways, with the design of the newer engines “ of the auto throttle “
It will either hunt at tick over and run smooth under load . Or run smoothly then bog under load..

 

[bogieboy]

If you have not had the pilot jet out it is probably blocked. Take it out and
put your cleaner though it and make sure it is clean. As I said in one of
my other threads if you are going to ream it out be carefull how you go
about it. Just use the next size up and don't go big at the start. It's like
cutting timber if you take to much off you can't pull it back on.

They are techincally nonremovable in this carb, small brass sleeve pressed into the body under the screw... i cant get at a carb anymore tonight but can show tomorrow....

 

[bogieboy]

Then push it along so it’s under load
I don’t think you can have it both ways, with the design of the newer engines “ of the auto throttle “
It will either hunt at tick over and run smooth under load . Or run smoothly then bog under load..

You can.... by reaming the pilot jet to whatever size the engine really needs...i do this crap for a living.... did everyone back in the 60s and 70s settle for a surging idle on thier cars? Nope.... properly size the jets and it will run correctly...

 

[Merkava_4]

This....

Straight down under the screw, theres a small brass insert, that is your pilot jet, that is what needs to be reamed out ever so slightly.

OK Good. We finally got to the bottom of this. If the pilot jet is a #35, would the next size up be a #40 ?

The reamer sizes are :

Ø: 0.33; 0.4; 0.45; 0.5; 0.6; 0.7; 0.75; 0.8; 0.9; 1.0; 1.1; 1.2; 1.4; 1.6; 1.8; 2.0 mm


STAHLWILLE 74310001

 

[bogieboy]

OK Good. We finally got to the bottom of this. If the pilot jet is a #35, would the next size up be a #40 ?

The reamer sizes are :

Ø: 0.33; 0.4; 0.45; 0.5; 0.6; 0.7; 0.75; 0.8; 0.9; 1.0; 1.1; 1.2; 1.4; 1.6; 1.8; 2.0 mm


STAHLWILLE 74310001 View attachment 447879

Yeah, if its #35, go to a #40... i just use the dental bits that are tapered, and having done it many times just go by feel, and just take a tiny bit out of the jet...

 

[bogieboy]

Heres a decent shot of the jet thats under the screw