Air / Fuel meter

[Ken-Ark]

Any one use one of these and have any reviews ? I see a lot of post that their carb isn't adjusted right . I guess you could weld in a bung and install this temporarily to check under different load conditions . $40




https://www.ebay.com/itm/403711222313

 

[RM-MN]

A lot of the posts about the carburetor not being adjusted right probably are caused by a set of points that need replaced. These old tractors are a low performance engine and the slight difference carburetor adjustment needed for perfect fuel/air mix isn't very critical.

 

[8NChris]

(quoted from post at 17:15:26 11/29/22) Any one use one of these and have any reviews ? I see a lot of post that their carb isn't adjusted right . I guess you could weld in a bung and install this temporarily to check under different load conditions . $40




https://www.ebay.com/itm/403711222313

ood idea. I'll use one when I get around to tweaking the 9N's aftermarket carburetor.

Would 12.4 be rich enough for our old flatheads?

 

[ASEguy]

On an engine like these, I set them by ear or a vacuum gauge.

 

[Hobo,NC]

Looks like no takers... : (

What is the difference between a wideband and narrowband O2 sensor?
A wideband o2 sensor gives you the data you and your ECU need to be able to tune that properly. While a narrowband can only tell you when it's 14.7:1, and is therefore nearly useless for tuning for anything other than a steady cruise condition.

I don't think its useless it may help one that is not accustom to tuning a carb tune in his ear to the adjustments. That's the hard part understanding what you hear/see/smell and feel.

A standard carb has no feedback (self adjustment) so tuning with that unit on the ragged edge may get you in trouble.

I will stay with hear/see/smell and feel I would like to see it in action tho : )

 

[Nyquil Junkie]

I don't think these old engines are quite that precise. Using one of these meters would be like using it on a lawnmower. The level of detail is good for a computerized EFI engine trying to get good MPGs, but for a 70 ish yr old carb?

I agree with the others... if it sounds right and smells and feels right, its as good as you'll get.

When engines start needing this level of tuning, they stop being as forgiving as these old engines are.

Might be interesting to have on there and watch.

 

[Royse]

I have not used one of these but agree that it might be a neat novelty to see what it says.
I also agree with RM-MN that many carb problems are found in the ignition vs the carb.
Probably way overthinking the issue at hand, but if folks have spare time and money, why not?

 

[8NChris]

They may seem tedious at first sight. I started using one on my carbureted pickup a few years ago. Found a few points to trim on different carbs that other wise ran fine. It beat the heck out of pulling over and checking the plug burn to dial in the fuel curve. Of course the N just has a 4 cylinder that doesn't turn much over 2000 rpm, but it is still an air pump.

 

[HarryVanderpool]

On our older equipment, I have become very confident in the use of a vacuum gauge for fine tuning.
Unfortunately, the 2N has no port for connection.
Not sure about The Junk Pile (8N).
Back in the early 1960s living in Minnesota, the big fad was everyone and their uncle had a vacuum gauge mounted on their dash. The goal was to keep the vacuum as high as possible while driving for fuel economy. Also might have indicated problems as they arose.

 

[my05hammer]

The difference between a wide band and
narrow band is that the wide band gives
you live accurate detail and readings
instantly. That cheap AFR gauge you have
shown may or may not get the job done. I
know from 1st hand experience that the
wide band sensor itself, if you buy the
good Bosch wide band sensor (PN17025) it
costs around $80. I am willing to bet that
guage doesnt come with the sensor.

I myself wouldnt mess around with one of
these AFR gauges unless the engine is
boosted. These old tractors are carbed and
so simple that just doing the old school
method of checking the plugs should get
the job done. But if you really want to
add an AFR gauge I'm not going to fault
you. But do yourself a favor and buy the
AEM Eugo 30-4110 AFR gauge kit. Its
$175ish and comes with the Bosch sensor. I
am using the AEM kit on a car I have that
has a big cam and 13 psi of boost making
800hp. (It is absolutely a requirement on
that vehicle at this point)

 

[Dave G9N]

(quoted from post at 19:58:26 12/05/22) On our older equipment, I have become very confident in the use of a vacuum gauge for fine tuning.
Unfortunately, the 2N has no port for connection.
Not sure about The Junk Pile (8N).
Back in the early 1960s living in Minnesota, the big fad was everyone and their uncle had a vacuum gauge mounted on their dash. The goal was to keep the vacuum as high as possible while driving for fuel economy. Also might have indicated problems as they arose.

his a vacuum port from a 2N tractor. It goes between the carb and manifold. It was used for a vacuum milker.

 

[HarryVanderpool]

Thanks, Dave!!
I'll make one for diagnostics.
Bolt it on and test, then remove.
Thanx!!