'74 "F" carburator is driving me nuts!

[IDave]

A '71 manifold should fit your 74 just fine.

 

[caz]

A '71 manifold should fit your 74 just fine.

Excellent. Thanks!

 

[Pin_Head]

Ok, still nothing!!! This is driving me insane!!

snip

If it were a vacuum leak, I sure can't tell where it is coming from. I sprayed carb cleaner about and didn't find one. There just aren't many places that a vacuum leak could be!

Anyone have any thoughts?

A few questions come to mind:

What is the function of the thing that I am calling the power valve?

What is the function of the solenoid? I did verify that this works with 12v to it



A frustrated,
CAZ

Rough idle and idling better with the choke on is a classic indication of a vacuum leak. When you had the carb off, did you check the bottom of the intake manifold for a crack? This is a pretty common problem. Leaky brake booster is another common problem.

If it is not a vacuum leak, then the idle circuit isn't providing enough fuel. The solenoid cuts off the idle fuel, so it needs to be working properly when it is in place. The power valve is an auxiliary main jet that richens the mix at high load conditions and leans it out at cruise conditions.

If the idle solenoid is working then the other possibility is that the idle circuit is plugged or partially obstructed. How did you verify that it is clear? You need to blow some compressed air or spray cleaner through the circuit to tell if it is open.

 

[Klunky Chris]

I sprayed carb cleaner all around the carb and the idle did not increase.

If you do have a vaccum leak and you spray carb cleaner into the leak it should stumble the engine. Carb cleaner doesn't make the engine run *better* but *worse*

just thinking you might not have been looking for this and missed it.

 

[caz]

Well, to wrap this thread up and to provide advice for future idiots like myself, we figured it out last night!

Somewhere along the line the JETS GOT SWITCHED!!!!!

I don't know if we did it when we cleaned it out, or if the PO did it - but switching them around made the thing run so well I thought I was going to ...... ummmmm nevermind

Thanks again to everyone for the suggestions and help!


<blushing at idiot mistake>
CAZ