Weber 44 IDF Question Options

[jmill]

Here is what I have in the carbs - been on travel and have not had a chance to mess with the car yet.

idle jet = 55, main jet = 145, F11 emulsion tube, 200 air correction

Your problem sounds just like a clogged idle jet. Turn mixture screws in until they bottom out while idling, one at a time. Don't over tighten. Go just until it touches bottom. The engine should stumble. Turn it back out until engine runs smooth. Do that for each idle mixture screw. If you find one that doesn't affect idle, that's your clogged idle jet.

You may also have a big vacuum leak. Check for intake and carb gasket leaks.

[orbit398]

Fuel, heat and air cause a backfire. I once blew a muffler clean off of a 1979 Ford Fairmont.

Check for exhaust leak sucking in air, check for an over rich mixture and make sure valves are adjusted correctly. IMHO it's one or a combination of those 3.

_________________________
Here is what I have in the carbs - been on travel and have not had a chance to mess with the car yet.

idle jet = 55, main jet = 145, F11 emulsion tube, 200 air correction

Venturi size?

--------------

whatever a Weber 44 is, idk

[stugray]

Fuel, heat and air cause a backfire. I once blew a muffler clean off of a 1979 Ford Fairmont.

Check for exhaust leak sucking in air, check for an over rich mixture and make sure valves are adjusted correctly. IMHO it's one or a combination of those 3.

_________________________
Here is what I have in the carbs - been on travel and have not had a chance to mess with the car yet.

idle jet = 55, main jet = 145, F11 emulsion tube, 200 air correction

Venturi size?

--------------

whatever a Weber 44 is, idk

The venturis can be changed out. Look down the barrel and you may see the size cast into the side of the vents at the top.

You can barely see the number at the bottom of this pic:
(IMG:http://www.914world.com/bbs2/uploads_offsite/i434.photobucket.com-10819-1478714200.1.jpg)

[Elliot Cannon]

Fuel, heat and air cause a backfire. I once blew a muffler clean off of a 1979 Ford Fairmont.

Check for exhaust leak sucking in air, check for an over rich mixture and make sure valves are adjusted correctly. IMHO it's one or a combination of those 3.

_________________________
Here is what I have in the carbs - been on travel and have not had a chance to mess with the car yet.

idle jet = 55, main jet = 145, F11 emulsion tube, 200 air correction

Venturi size?

--------------

whatever a Weber 44 is, idk

I use Weber 44idf's. My venture size is 34.

[BigFour1973]

Hijack number 2.....

I'm having the same issues stated. Car runs on 3 cylinders from idle up until 2300-3000 then it smooths out and pulls. When I decel, it goes back to 3 cylinders and back fires like crazy.

-I isolated it to cylinder number 4 by pulling plug wires.
-pulled all jets, hit them with carb cleaner and inspected
-R/R new rotor, cap and plugs.

Anything else I should check?

F11
Air corrector 175
Idle jet 52
Main jet 135

Car is a 2.4/4 with flame thrower coild and points eliminator

TIA

[Keith914]

I have same 2.4. With help of air/fuel mixture gauge, my Webers have; 55 idles, 150 mains, 200 air corrections with 34 venturies in these 44's. Runs great with good A/F ratios.

[GeorgeRud]

On a 2.0 liter 914 engine, I wonder if the 44 Webers with 34mm ventures may be too large and so don't provide the proper amount of a signal at idle or low rims. In reality, an air/fuel meter will probably be the best diagnostic tool.

And yes, the ethanol laced fuel does cause all sorts of issues with turning into a gel like substance, especially in a humid environment.

[rhodyguy]

32s may result in better/smoother low end response in your application. It's a relatively easy swap but you'll need to go thru baselinning your carbs again. Following the procedure as detailed in the CB manual makes short work of that task.

[BigFour1973]

Thank you all for the responses, I'm a newbie to the Webber 44s. Although not a newbie to carburetors themselves so I get the principal.

I tweaked the mixture screw on #4 cylinder and got it to come back to life. Drove her over to the car wash a couple miles away and on my way back I lost cylinder #2. Same issue, except this time I could back the screw all the way out with the car running and there was no change. Screwed it all the way in and again, no change.

Spark notes:
All things noted below are issues at idle, off idle/transition to main.

- lost cylinder 4, messed with mixture screw and got it back to life
- lost cylinder 2, messed with mixture screw to no avail.

Could it be bad gas?
Could it be due to the desert climate that the car was parked in for the last 4 months gunking up the jets?

[Elliot Cannon]

Thank you all for the responses, I'm a newbie to the Webber 44s. Although not a newbie to carburetors themselves so I get the principal.

I tweaked the mixture screw on #4 cylinder and got it to come back to life. Drove her over to the car wash a couple miles away and on my way back I lost cylinder #2. Same issue, except this time I could back the screw all the way out with the car running and there was no change. Screwed it all the way in and again, no change.

Spark notes:
All things noted below are issues at idle, off idle/transition to main.

- lost cylinder 4, messed with mixture screw and got it back to life
- lost cylinder 2, messed with mixture screw to no avail.

Could it be bad gas?
Could it be due to the desert climate that the car was parked in for the last 4 months gunking up the jets?

After my car has set for a few months without running, the carbs will dry out resulting in clogged idle jets.

[Keith914]

Fully out and fully in mixture screw will not work. Finding the sweet spot takes gradual adjustments, best starting from about 1/4 turn out from closed. Give each adjustment time to "settle in". Agree with above, clean idle jets also often clears problem.

[BigFour1973]

Pulled the idle jets and no visual obstructions. Blew them out any ways and still getting 3 cylinders.

Located 2 vacuum leaks from where the intake runners and head meet on both sides. tightened those guy and no more vacuum leak. Still getting 3 cylinders.

Pulled plugs to inspect, and check the gap. All is good there too. Had to throw in the towel last night. next is going to be total tear down of the carbs and inspection of the galleys.

Updates coming soon.

[72hardtop]

With a 2L you'd be miles ahead with 40IDF's (better low RPM flow) than with the bigger throat 44's.

Jetting for a 2 liter with 40IDF's:

28mm vents
50 ildes
120-125 mains
180 air corrector jets
F11 tubes
Fuel pressure no more than 3.5lbs max


And get your hands on an LM-2 Wide band