Anyone know alot about Carb jetting?

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Anyone know alot about Carb jetting?

February 19, 2006, 07:19:13 PM

My engine has a rebuilt Motorcraft 2150 carb and I still don't feel that it's operating efficiently. Lately I've come to suspect it's the jetting that's the problem since Calgary sits at around 3000 feet and I read somewhere that high elevation carbs need a smaller jet. Neither manual I have has much to say on the subject, does anyone know of an article or have some expertise?

Anyone know alot about Carb jetting?

Reply #1 – February 19, 2006, 09:34:28 PM

The higher alt has thinner air,thus it would work better with a smaller jet. Hope this helps

Anyone know alot about Carb jetting?

Reply #2 – February 20, 2006, 12:51:25 AM

In the '84 shop manual there are two versions of the 2150-2v.
One version has altitude compensation.
On the right side, foreward of the choke pulldown diaphragm, there is a cylindrical thing called a aneroid assembly. It sticks out about as far as the choke pulldown.
Its function is to lean the fuel air mixture.
"It is a gradient type: opens on a nominal basis at 549 meters(1800ft) and has compensation capacity beyond 3048 meters(10,000ft)."

Anyone know alot about Carb jetting?

Reply #3 – February 20, 2006, 12:25:59 PM

wonder if you might consider getting a rebuid kit for it. maybe thats all it is. One thing i think would help in troubleshooting is to spary wd40 up in the vac assisted choke pull off you mention. I could be not actuating all the way. I had a CFI off an 83 with vac assisted plungers instead of the motor control type. I was wondering if this cfi setup was for high elevations as well.

Anyone know alot about Carb jetting?

Reply #4 – February 20, 2006, 12:34:22 PM

Quote from: softtouch

On the right side, foreward of the choke pulldown diaphragm, there is a cylindrical thing called a aneroid assembly. It sticks out about as far as the choke pulldown.
"

I misinterpreted the picture. the aneroid assembly is on the rear of the carb to the left of the choke pull down.

Anyone know alot about Carb jetting?

Reply #5 – February 20, 2006, 05:58:28 PM

I just looked and my carb doesn't have this aneroid assembly.

Anyone know alot about Carb jetting?

Reply #6 – February 20, 2006, 07:07:05 PM

It probably ought to have a rebuild... The 2100 carbs are as simple as they come, and lowereing the float slightly has the same effect as installing smaller jets. Which by the way will be hard to find, as the Motorcraft carbs use a larger thread than the common Holley jets...

Anyone know alot about Carb jetting?

Reply #7 – February 20, 2006, 08:16:02 PM

I bought the carb rebuilt actually. It's only a few months old.