Autolite Holley 1940?

[phoenix02]

No, not that spring- I have that one. I'm talking about the diaphragm on the OUTSIDE of the 1940, on the driver's side- 1st, is there supposed to be a spring inside, like under the dashpot on the 1100? If so, could I use the return spring on the dashpot on the 1100? Also, what exactly is that diaphragm for? It's actuated by the choke arm, but I don't see it really moving much. What does the spring on the outside of the diaphragm do? It's kinda just attached to itself, really, ya know?

-Michael

 

[Mercury Mike]

Ohhhhh! Yeah, you can use the autolite 1100's spring there. =) They are interchangeable, and I only keep one set around depending on which carb I use I just switch it up. No big deal. You're in good shape. I will send the throttle rod when I wake up. =)

 

[phoenix02]

Okay gents,

I got her bolted up. poured a little gas down the venturi, turned her over for about 3 seconds and she fired right up! No more priming it, like with the 1100, no more stalling- she runs and drives now!

Problem 1- The idle mixture screw STILL seems to do nothing on this carb! I turned it all the way in and it still idled the same, no difference.

Problem 2- NO power, just like with the 1100. I pulled the 1940 apart and checked to make sure everything was on the way it should be, and it was all good. Still though, from a standing stop, I give it gas, it feels like it's going to die- BIG flat spot- then spools up slowly. When I give it gas stopped in park, she roars very nicely. The timing's good, plugs are new Autolite 46s, properly gapped, new wires, rotor and cap, need to install the new points... Since I'm having the same prob with a second carb, I'm wondering if it's something with the engine- cam timing or something? When you get her up to speed, she cruises at 90 and still wants some more, but until about 50-60, she just spools up slowly. Any ideas? This is the first engine the guys that put it together built, so I doubt they properly degreed the cam and all that.

-Michael

 

[Mercury Mike]

Well let's shoot this question at the crowd: It revs up great in park and neutral, shifts good and everything. What are some reasons that a car would be super bogged under load, as opposed to not in drive? Vacuum leak or...?

 

[addo]

Poor valve clearances, bad valve timing, incorrect ignition advance curve. Check plug gaps, too.

 

[JackFish]

If the 1940 has a power enrichment valve like the 1946, these can become sticky in their bores and won't react to vacuum changes as they should.
The valve on mine is a plunger and piston built into the top, facing down.
The plunger hits a needle valve, and the needle can become damaged as well.
I have opened up olds carbs and found both completely stuck and gunked up as well.

 

[JackFish]

Problem 1- The idle mixture screw STILL seems to do nothing on this carb! I turned it all the way in and it still idled the same, no difference. -Michael

This can mean that the curb idle screw is out too far and the butterfly doesn't close far enough to shut the transfer circuit.
When the butterfly is "closed" there should be just a hairline crack of an opening if you look at it from the bottom.
It could also mean the mix screw is damaged or worn out.l

 

[Mercury Mike]

Mike, don't forget that until you get that throttle rod, and a good return spring, your carb isn't gonna close all the way. Hold it closed at the throttle, and set the idle. =)

 

[JackFish]

Here ya go!
http://cgi.ebay.ca/1969-Ford-Autolite-1 ... dZViewItem
Free shipping!