Author Topic: 4100 float setting  (Read 604 times)

Offline Hipo giddyup

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4100 float setting
« on: November 23, 2017, 02:15:57 PM »
So I finally got my 66 coupe on the road. I put about 80 miles on it so far and I noticed that it’s a little hard to start? Looks like I’ll have to go over the timing but I did notice that when readjusting the choke, the secondary venturis were wet looking? Don’t think this is supposed to be so I’m wondering how this could be getting fuel when the car is that idle? Carb has been rebuilt, all the gaskets are new, and the floats were set when rebuilt to the rebuilding specifications. Maybe the rear float needs rechecked or adjusted? Or maybe something is failing? Thanks for any replies
1967 Springtime Yellow Coupe, 289 2v 3spd, Metuchen built, Nov. 17th 66'
1966 Sahara Beige Coupe, 289 2v 3spd, Dearborn built, July 21st 66'
1964 1/2 Pagoda Green Coupe, 260 2v 3spd, Dearborn built, June 30th 64'
1966 GT350 Fastback clone, 289 HiPo, 725cfm Holley, 4spd, SanJose built, Nov 25th 65'

Offline Hipo giddyup

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Re: 4100 float setting
« Reply #1 on: November 23, 2017, 02:17:08 PM »
Forgot this,, 1966 289 C4 automatic, 4100 carb.
1967 Springtime Yellow Coupe, 289 2v 3spd, Metuchen built, Nov. 17th 66'
1966 Sahara Beige Coupe, 289 2v 3spd, Dearborn built, July 21st 66'
1964 1/2 Pagoda Green Coupe, 260 2v 3spd, Dearborn built, June 30th 64'
1966 GT350 Fastback clone, 289 HiPo, 725cfm Holley, 4spd, SanJose built, Nov 25th 65'

Offline jwc66k

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Re: 4100 float setting
« Reply #2 on: November 23, 2017, 02:49:40 PM »
Depending on the source, 29/64 to 1/2 inch for the primary; 29/64 to 5/8 inch for the secondary. Don't you just love precision?
What is the Ford number on the carb base? What is the letters on the booster venturis? The wrong secondary booster will give a different vacuum signal to open the secondary diaphragm. 
Jim
I promise to be politically correct in all my posts to keep the BBBB from vociferating.

Offline Hipo giddyup

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Re: 4100 float setting
« Reply #3 on: November 23, 2017, 05:52:21 PM »
 Thanks Jim. The secondary boosters are correct, I believe they are BA.  I would have to pull out the spec sheet that I used but I’m pretty sure that the fluid levels are adjusted properly. I’m hoping that the measurements for my spec sheet would match what you found.  I have had the top off before, when doing some minor work, and saw that the gas levels were well below the top of the carburetor.
  When the car is running it looks like something is leaking fuel through the Venturi’s and every so many seconds I do see what appears to be a drip down towards the secondary throttle plate. Don’t think this is right. Maybe I’ll take the top off and retighten to see if the booster assembly might be loose or not tight enough . I have  another gasket I can throw in there as well.
1967 Springtime Yellow Coupe, 289 2v 3spd, Metuchen built, Nov. 17th 66'
1966 Sahara Beige Coupe, 289 2v 3spd, Dearborn built, July 21st 66'
1964 1/2 Pagoda Green Coupe, 260 2v 3spd, Dearborn built, June 30th 64'
1966 GT350 Fastback clone, 289 HiPo, 725cfm Holley, 4spd, SanJose built, Nov 25th 65'

Offline Hipo giddyup

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Re: 4100 float setting
« Reply #4 on: November 26, 2017, 11:09:47 PM »
Got some time today to look at the 4100 leaking gas via the secondaries. I replaced the gasket underneath the rear booster and the small round gasket under the retaining screw. I noticed that when I took the booster off the cylindrical holes where the tubes of the booster go down in, were full to the top with gas.? After replacing the gaskets I ran the car for a bit and noticed wetness on the boosters still. When I had the top of the carb off I verified the rear float is set correctly. Now that I am still seeing wetness I’m guessing the needle is not fully sealing the valve which must be letting gas come through the boosters and drip?? I have another needle and valve so I will replace that next and see if it seats, stopping the gas from dripping down the booster. Any other ideas?.
1967 Springtime Yellow Coupe, 289 2v 3spd, Metuchen built, Nov. 17th 66'
1966 Sahara Beige Coupe, 289 2v 3spd, Dearborn built, July 21st 66'
1964 1/2 Pagoda Green Coupe, 260 2v 3spd, Dearborn built, June 30th 64'
1966 GT350 Fastback clone, 289 HiPo, 725cfm Holley, 4spd, SanJose built, Nov 25th 65'