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Luva65wagon
January 4th, 2012, 12:02 AM
As you may or may not know I couldn't get the Flarechero running right with the carb I got with it. Steve had purchased it for $150 from his side of the world when the car was his, and it seemed to run "OK" to get the car over here. Jeff had borrowed it to test for some issues on his wagon and, like his, indicated a leak at the throttle plate. After an initial inspection and cleaning, I thought it was better, but not right at all.

So I pulled it off the Flarechero and put the Holley 1940 from the wagon onto it. It started instantly and with a little tweaking the 1940 runs famously and is at home for good on that motor since it didn't have the Spark Control Valve needed for the Load-o-matic distributor, which the wagon has, but the Flarechero doesn't need.

For what it's worth, the Holley 1940 is a "service replacement" Ford issued when the 1100 Autolite was discontinued in 1969. It was never offered as a factory installed carb, but may be the carb offered when you buy one for a Falcon/Mustang. You should always verify whether you need a spark control valve and whether your carb has one (a mistake I learned the hard way).

Tonight I pulled the 1100 out of the bath it has been taking for just shy of a week and proceeded to blow out all the orifices to make sure they are all open. Everything was.

As I was blowing things out and feeling for where air came out, I felt air coming out of a spot I didn't think air should be present; namely, the press-in/peened plug over the power valve vacuum cylinder. DING-DING-DING!

The symptom while on the Flarechero was rich running and stumble at idle. The symptom fits.

A power valve allows for an enrichened mixture under continued acceleration - after the accelerator pump squirt has been used up. It is directly vacuum related (dang, this subject keeps coming up). At idle the power valve should see full vacuum and should (in the case of the 1100) suck a rod upward to press a ball-check and close off the source of fuel. With the help of Gene, who happened to stop by with his crank pulleys, I hooked up a vacuum pump to the port feeding vacuum to the power valve, plugged off another port in the venturi also feeding this - and pumped. The valve moved a little. I then plugged the cap with my thumb and pumped - sucked the valve closed.

So, with the power valve not closing at idle there was a lot of fuel dumping and that led to both the inability to adjust the idle speed and a very rich mixture - which was why fuel was pooling and dribbling out the throttle plate shaft.

At least that is what I currently believe.

I mixed up some JB Weld and put a little over all the plugs on top of this carb to seal any vacuum or fuel leaks it may have. Proof will be the assembly and install - on the wagon. Wish me luck.

Luva65wagon
January 4th, 2012, 11:36 PM
It's back together with the exception of the fuel inlet, which I'm going to try and replace. It was really loose in the pipe threads, and using a new 1/8" NPT fitting there was threads left to tighten, where this one bottomed out and was still loose. An 1/8"NPT to 5/16" inverted flare should be easy to find.

As you see in the pictures, the power valve sticks down into the fuel bowl. It sits next to the jet, in fact. At idle, with full vacuum, this rod should move up and push against the ball you see exposed just inside the shaft. Problem was that the top of the carb, where everyone has whacked on it over the years to "free the float valve" [or whatever] distorted the cap above the vacuum ram that is supposed to pull that rod up. At idle, if that ram doesn't get sucked up - you probably get more fuel flowing than you do through the jet. Stinky, stinky (and I wasn't using the carb when that girl yelled that). :o

So I decided to JB Weld every plug. I knew the big cap was leaking like a sieve, but you can never be too careful.

The venturi in these carbs are plastic and peened into place. This way they could make one body and size it depending on what part they put in. There are 3 sizes; 1.00, 1.10, and 1.20. I think I edited my image wrong, but I've got the 1.10 size, I suppose. It's a little bigger than that at 1.120. I guess, at this stage, you get whatever you get if you buy them. I think you'd have to start collecting these to build one with the exact specs you wanted.

Also, note the Spark Control Valve on the side of this carb. It is often mistaken for the power valve because it looks like a power valve found in Holleys. It is this thing that controls the advance vacuum to the Load-o-matic distributors... which I've been driving 15 years without. Looking forward to seeing what the car runs like with it.

Luva65wagon
January 7th, 2012, 09:15 PM
Started the wagon up today with this 1100 on it - ran famously. I have not taken it out yet (musical cars wasn't in the plan for today), but just running it in the garage - it sounds way different. Maybe because it has vacuum advance now? Maybe?
:o

Luva65wagon
January 9th, 2012, 10:57 AM
Drove the wagon last night after coming back from working with Gene. It does perform totally different with this carb on it. Not like it was gutless before (for a 6), but I climbed a steep hill by my house with no problems. So, made some progress there. The Holley on the Flarechero works well when it is running, but it starts very oddly. More on that elsewhere.