Natural Gas Engine Tuning?

[skegpro]

Got a new natural gas generator.
Any advice on how to set the fuel on an natural gas engine? I was thinking of getting a AFR guage?

Will any AFR gauge do?

 

[skegpro]

........

 

[team dirt]

Give it 7” of pressure and I’m sure that’s all it will need.

 

[DRD]

Can just use a vacuum gauge. Load the **** out of it and adjust to highest manifold vacuum.

 

[skegpro]

A guy doesn't have to pay attention to exhaust gas temp?

I was told if it has to much excess fuel it would run real hot.
Risk melting headers......

Don't know how true this is.

 

[skegpro]

Can just use a vacuum gauge. Load the **** out of it and adjust to highest manifold vacuum.

Sorry I am not the sharpest engine guy.

Can you explain a little bit where to tie in.

What will the highest vacuum tell me?

 

[lilduke]

Why didnt you go with solar panels?

 

[skegpro]

Why didnt you go with solar panels?

Oh you know, I don't wanna freeze to death.

 

[jpmez69]

Sorry I am not the sharpest engine guy.

Can you explain a little bit where to tie in.

What will the highest vacuum tell me?

Run the engine at whatever load you will see. Set it up to 5" H2O on the fuel reg. Install a test port on your intake manifold and you will then be setting your manometer to InHG. You will then adjust the load screw rich on the carb until you reach your highest vacuum and stop there. Then you will turn the load screw 1/2 InHG lean and that's it. If you want best power and reponse leave it at the hightest vacuum under load. If you want best fuel economy at a lighter load and lower carbon build up run it at 1/2 InHG lean.

That's a nice gen package with the Chevy 4.3L. With reg oil changes these engines will almost run forever.

 

[skegpro]

Run the engine at whatever load you will see. Set it up to 5" H2O on the fuel reg. Install a test port on your intake manifold and you will then be setting your manometer to InHG. You will then adjust the load screw rich on the carb until you reach your highest vacuum and stop there. Then you will turn the load screw 1/2 InHG lean and that's it.

Awesome thanks.
Where do I get a good guage to do this?

 

[gunner3006]

Your best way is a combustion analyzer and a manometer. Assuming you don’t have an analyzer a manometer is your best bet. If your using 7-14” wc which is standard house or farm setup, be sure not to strain your other appliances when starting up or testing.

 

[jpmez69]

Awesome thanks.
Where do I get a good guage to do this?

You can buy a digital manometer with all the different pressure and vacuum settings. Or buy a cheap slack tube H2O and InHG but then your dealing with real murcury. Probably can't even buy murcury any more. BTW don't let the murcury be drawn into the engine!

 

[team dirt]

Awesome thanks.
Where do I get a good guage to do this?

Where are you at. I have an analyzer and manometer if your close to brooks.

 

[Cableguy]

thats sweet how many kws

 

[DRD]

A guy doesn't have to pay attention to exhaust gas temp?

I was told if it has to much excess fuel it would run real hot.
Risk melting headers......

Don't know how true this is.

Gaseous fueled engines get hot when they go rich, no fuel vaporizing to pull heat like gasoline engines. Lowest vacuum tells you the mixture is ideal and you are are at the lowest amount of throttle required to carry the load. All the compressor guys coming out of the wood work lol. Check amazon for a digital manometer.

 

[skegpro]

Gaseous fueled engines get hot when they go rich, no fuel vaporizing to pull heat like gasoline engines. Lowest vacuum tells you the mixture is ideal and you are are at the lowest amount of throttle required to carry the load. All the compressor guys coming out of the wood work lol. Check amazon for a digital manometer.

Awesome, that makes sense thanks.

Yeah I am just a farming instrument guy.

But I figured there must be a few compression gurus on here.

 

[skegpro]

thats sweet how many kws

40kw, single phase.

 

[skegpro]

Where are you at. I have an analyzer and manometer if your close to brooks.

Just east of Edmonton, but thanks!

 

[skegpro]

This is the old girl we yanked out.

 

[jpmez69]

Gaseous fueled engines get hot when they go rich, no fuel vaporizing to pull heat like gasoline engines. Lowest vacuum tells you the mixture is ideal and you are are at the lowest amount of throttle required to carry the load. All the compressor guys coming out of the wood work lol. Check amazon for a digital manometer.

On a n/a engine lowest vacuum= throttle plate wide open. A balled out engine at max load. Highest vacuum= throttle plate at idle with no load. If you run the engine at it's leanest with low manifold vacuum, when additional load comes on you will lose RPM and go down on underspeed. An exhaust analyzer wouldn't do you any good unless you know what the o2% is for that engine. In any case they would be super rich in the range of .5% o2