1100 Carb Venturi Problem?

[Fairlane Fixer]

Hey all, I need some input

I have an Autolite 1100 on my '63 and it's giving me problems
by gas gushing rapidly into the venturi after shutting the engine
off.

During idle I cannot get the air/fuel mixture right. The mixture screw
has to be screwed all the way in just to get it to idle. Seems like if it
could screw in more it would smooth out but it's bottomed out.

I had the carb checked out by an experienced mechanic and he said
the float level, neddle and valve, etc is set perfect. Then he said the
plastic insert venturi looked like it wasn't sealed right and messed up
which could possibly cause an erratic air flow causing my symptoms.

Is this true? Why is there a plastic insert? Can it be removed and the
carb still yet be usable?

Sorry so long, but I need all the help I can get.

Sincerely
Fairlane Fixer

 

[CZLN6]

Howdy Fairlane Fixer:

No, the venturi insert cannot be removed. It should be solidly seated to a ledge at its bottom. The carb will not run correctly without it. IF the insert is fitting loosely, it should be resecured in place with some epoxy cement.

It sounds to me like you have a sticking float needle valve for the gushing gas on shut off.

The low speed air screw problem sounds like a vacuum leak somewhere.

Is this an original '63 200 in your Fairlane. Casting numbers of C3DE on the block would verify.

Hope that helps you.

Adios, David

 

[Fairlane Fixer]

Thanks David,

The car did have a "T" code 200 C3DE but
it now has a '68 C8DE.

Could this pose a problem?

Can this be fixed?


Thanks

 

[CZLN6]

Howdy Back:

No, the later block should be no problem in this application.

Yes, the venturi insert can be re-attached and the carb fixed. You'll need to disassemble it to fix it. Watch carefully for bad gaskets, cracks, and split vacuum lines or hoses when reassembling. That's the likely cause of the vacuum leak.

Is the carb the '63 or the '68 1100? Which distributor? The '63 carb is a better choice for performance as it has a 1.2" venturi. It needs a Load-O-Matic distributor. The '68 carb has a 1.1" and has no SCV, so needs the '68 non Load-O-Matic distributor. If your '63 Fairlane came with a 200 engine I'm assuming you have a 2 speed auto trans?

Adios, David.

 

[Fairlane Fixer]

Hey David,

The entire engine, dist., etc is a '68 (7-bolt main) C8DE.

The carb is a '63 with a spark control valve.
Can this be a problem by not having a load-a-matic dizzy?
Maybe the wrong vacuum signals going to the advance making
tuning difficult.

Can the spark control valve be plugged?

I don't think the is causing my flooding issue.

Sincerely,
Fairlane Fixer

 

[CZLN6]

Howdy:

Yes, the mismatch of carb and distributor can cause efficient running problems. It is not the cause of spurting gas at shut-off, or poor idle.

The later distributor will do best with a later carb with a proper ported vacuum source. That includes the '68 and '69 downsized 1100s and the next OEM 200 carb, the Carter YF. The down side of the YF is that they used a side mounted throttle cable rather then your stock linkage.

Another option is to use an 1101 Autolite from a '69 250 Mustang carb for a performance upgrade.

The '68 distributor is a better unit than the L-O-M. It has centrifugal and vacuum advnace.

The SCV port on the on the '63 1100 can be plugged, but it still will not have a correct ported vacuum source for the distributor. YOu could use manifold vacuum, but be careful when adding additional initial advance.

Adios, David