Close



Results 1 to 2 of 2
  1. #1
    FEP Super Member xctasy's Avatar
    Join Date
    Jun 2012
    Location
    Dunedin 9011, New Zealand, South Pacific
    Posts
    3,961

    Default Rebuilding the 1978 to 1979 Holley 1946 carb before idle control and bowle vent

    Afew people have asked what can be done to fix the cold stuble and off idle stutter coomon to 85 hp Fox 3.3 sixes.


    Most people have hot starting issues, and there is a lack of info on these carbs.


    The problem in hot areas is much like a car having hot fuel handling problems. Although not THE primary solution, such a set up works as a band aid repair. Ford anf GM did it when they decided not to do underhood shielding and other changes that Ford used with the 5.0 V8 HO carb cars from 1982 to 1985, cars that had 8.5 psi of fuel pressure possiable at the carb.


    Most people who work there cars, like to strip off the factory parts, and with headers, open air cleaners, and no fan shroad and air snorkles, you'll need fuel line blead back.


    Its like this car.

    https://www.youtube.com/watch?v=YUmaAQoHggM


    A return line solved it. The problem wasn't really fuel pressure, but what was done to the shrouding and the exhaust and carb. If factory Fox or F150 style shrouding and air cleaners were used, he'd not have needed any fuel pressure bleedoff.


    Ford Australia first had this problem during the Aussie Draughts in the early 80's, and the solution on the 1982 to 1992 in line sixes was to have a blead back return line to the fuel tank. The Carter fuel pump got revised like this below. Again, if Ford Australia had used some of the US style hoses, shrouding, and sperpentine drives, they could have kept the fuel pressure up like the 8.5 psi the 1982 to 1985 carb 5.0 Mustangs used, and just used the priority carb bowel vent, but they instead used the European Fiat carb. Go figure!

    As posted elseware, my 81 had a leaking D6DE 6749 AB fuel pump, and I couldn't quickly get a US$20 replacement item.

    I've added an Austrailian 1969 to 1981 FPM-000A pre 1982 Bendix made Carter A31223 non bleedback pump off my 250 X-flow to the related US 200 i6.



    The 1982-1992 Alloy Head Cross Flow Falcons, Fairmonts and Fairlanes had 2-bbl Weber ( a Fiat 131 style 34ADM) And a return line variant of the fuel pump above.



    That is perhaps the easiest solution to one aspect of your problem. Its certainly not stock solution for your years Ford Mustang though.


    On GM Holden 173, 202 sixes, and the 253 and 308 v8 engines, they used the same vapour line as the 1981 to 1985 VV7200 carbed Panther Platform cars like the LTDS, Crown Victoias, Grand Marquis etc. They had a device which blead back vapor pressure to the fuel tank. When there is too much vapor pressure, the needle and seat locks off and stops the car running right.



    Fuel pressure control and vapor control aren't exactly the same, and adding a set up like the ones above might help, but there are other ways to fix the stutter and idle issues.

    The issues and manner in which the stock 4.2, 5.0 AND 5.8 Panthers with the VV7200 carb did there job was discussed in post #8

    http://vb.foureyedpride.com/showthre...ng-tube-H-Pipe


    Anyway, the other issues that will be causing the actual problem.

    9 times out of 10, its this part,


    1. The intake manifold adaptor and its

    Vehicle Emissions Control Information=VECI, which governs
    Vacum, Emissions, Carb, and Ignition line settings




    The aluminum intake adaptor that links the carb to the iron head. On your 79, it has a problematic adaptor dating from 1974 that doubles as an EGR post, so it suffers hot and cold leaks, and sometimes has cracks that hurt the idle. The EGR function is tied in with the VECI diagram, and its important that any diodes to and from the AIR, EGR, and the Choke are correctly attached. Just having an MCA judged car doesn't mean the parts are correctly arrayed. There are about 70 emission control features on the 79. Any one of them can be the problem.

    Do ensure you snub the carb and carb adapter up evenly with a small torque wrench i9f you can, there is only two bolts 180 degrees to each other, and the whole 1-bbl carb wobbles like a b stard after a few years of service.

    Same with the 240/300/4.9 big six truck engines, a leaking carb base is such a common problem, and its sometimes hard to track, and even harder to take the hour or so to snub it down properly. You can do it with hand tools like a cranked open ended spanner, but unless the gaskets are right, its easy to unequally load one bolt, and get a leak.

    The recommended torque settings are here

    http://classicinlines.com/SmallSixSpecs.asp#TorqueSpecs

    Intake = 16-18 lb-ft


    Some 1-bbls on 144-170-200-250 and 240-300's have four bolts with two bolts down low, two up high, the two clocked at a weird angle. Leaks are so common.


    2. Ignition Settings and Components, namley "Advance Curve issues and non spefication parts (like ignition caps) that were sold that were out of factory spec in there plastic mouldings and spring tensions.

    Vac advance systems that are worn out, or aftermarket distributor caps that don't even have the six leads indexed the way that Ford intended. Although all Ford I6's are the worlds most simple sixes ever, they sure do have a bunch of really simple things that can be wrong that make 'em hard to tune.

    3. Electrical Earthing

    a) I'd look at the engine block earth to the engine first, make sure there is chassis to block continuty, and set up a second earth strap somewhere on the cylinder head. I'd ensure the Duraspark II has clean contact points and wire continuity. They are getting old, and wires that look and test as being items with continuity, aren't always fully functioning.


    b) I'd put the ignition advance and whole distributor on a Sun analyser to see that its in spec. I have two US contacts who I trust after many years of co work with the Ford Six Performance forum.


    c) The ignition switch needs to be checked.

    d) The battery may be shorting through its 9 plates...that can create non starting cars when hot.


    4. Mechanical Blueprint settings for timing, preload, backpressure, fuel supply volume and pressure variations

    I'd recheck

    a) the hydraulic lifter settings with a proper lifter setting tool that bottoms out the lifters, and then re-set the lifter preload clearances to spec.


    b) I'd then test the backpressure in the exhaust. The catalyst could simply be creating excess back pressure. More than 6 spi is too much at wid open throttle/4500 rpm.

    c) I'd renew the fuel pump, and then check the positioning of it to maximse peak pressure to 5 to 6 psi and total out put for 85 bhp net. Just preositioning the fuel pump on its bolts can change the stroke of the fuel pump, and fatten its fuel delivery pressure and out put.

    d) The other thing is harmonic dampener slip. The stock 9 Degrees Before Top Dead Center of whatever won't be as indicated by a timing light after a few years of dampener rubber ageing. The timing slips when rest to spec.

    In a similar way, within just six months of operation, the stock single row timing chain suffers a huge amount of spark scatter and cam duration change from acceleration to cruise. In terms of engine idle stability, the stock ignition timing is then out of whack, and it scatters under load and over run. A Mustang uses the same kind of timing chain dimensions as a twin row timing chain on an A series Healy Bug Eye Sprite, and it was used to tighten up idle quaity and timing. It got retrofitted to the late sixties Australian Ford Falcons to help improve safety under load (the cam can hit the con rods when the engines timing chain stretches with old age, but it always a good policy to upgrade it)



    Second lastly


    5. Its the Ultimate Econo Engine!

    http://www.mustangandfords.com/how-t...g-performance/
    The largest culprit with vintage Ford sixes is fuel distribution. Their integral log-style intake manifold, which was conceived to control manufacturing costs, makes these sixes frustrating to live with. They suffer from rough idle quality no matter how many different carburetors you try. They stumble off idle and surge or hesitate while cruising. We tend to blame these performance issues on the carburetor, but that isn't always the case. Poor fuel/air distribution along the integral intake manifold and into the cylinder head creates all kinds of performance issues. It can be the luck of the draw because no two castings are alike. Some sixes run like a clock while others can't get out of their own way.

    Turbulence along the log manifold tends to upset fuel droplets in suspension, which enter intake ports erratically. End cylinders tend to run lean while inboards run rich. To add insult to injury, Ford placed the one-barrel carburetor above a hot exhaust manifold, which causes all kinds of heat-induced problems (percolation and vapor lock) in hot weather.
    Some passing notes on the last thing to do.


    6. Rebuiding the Carb.

    The choke set up for 1979 chaged in the early 80's to the 25 psi of vac applied to the choke unloader. I'm not sure on what the 1979 spec is, but it has the EGR port proble, no control purge cycle for the car vent tube, and the adjustment for fuel enrchiment under throttle is by just bending the accerator pump wire.


    The 1946 Holley is just an advanced Autolite 1101, or Holley 1940, Holley 1945 (also branded as the Autolite or Motorcraft). Its similar to the Chrysler 1945 carb.

    Bending is the method for adding pump stroke to the accerator pump. On the old carbs from 1961 to 1969, it was via a triangular plate with sloted holes.


    The last thing I would do, after all esle, is rebuild the carb.

    Due to the problems with modern fuel, your best bet is to contact Will Ambler (was111) or Farron Rhoads "FordSedan Delivery", and have a second exchanged distributor recurved away from factory stock to remove the dead spot. A Duraspark II will cope with a huge amout of intial advance, and a greatly reduced total advance with a more aggressive spark advance growth.


    All these 6 things above things were changed by the Australians when the 1976- 1991 3.3/4.1 Cross flow, and the Americans six cylinder Falcon six derived HSC 2.3 and 2.5 came out in the Tempo/Topaz/Tracer and Tauruses between 1984 and 1986. They were not fixed on the US 3.3 because they were the worlds cheapest to build six cylinder engine.


    Hope this helped some.


    Carb is the last on the list, but the rebulding of it is simple. Internally, the Holley 1940, 1945, 1946 Brass Float is the same.

    The problem is that the 1940, 1945, and 1946 Holley's aren't the same carb externally, but readically different externally due to the choke position changes, and the vent tube changes. For a simple 1-bbl, its very prone to finding vac leaks, and having the check balls the wrong size, weight, or the specifications messed up.


    To rebuld the 1946, you have to follow the Mikes Carbs Holley 1940 rebuild, and then the 1945 Mopar Holley version, and then, lastly, work out what is different with the 1946.




    The 1946 kit.
    https://www.youtube.com/watch?v=7ALbDtnxvRo

    The 1940 kit

    https://www.youtube.com/watch?v=ra_pAzqRNlc

    The foundational 1940 Holley rebuld videos

    https://www.youtube.com/watch?v=CzHc0BKexlI

    https://www.youtube.com/watch?v=ht18I7djTZM

    The foundational Mopar 198/225 1945 Holley carb video

    https://www.youtube.com/watch?v=gBti9Y-5g60

    See http://vb.foureyedpride.com/showthre...L-3-3L-i6-help

  2. #2
    FEP Super Member xctasy's Avatar
    Join Date
    Jun 2012
    Location
    Dunedin 9011, New Zealand, South Pacific
    Posts
    3,961

    Default

    For roush235

    Check the item listed "HCI Valve" , the Hot Idle Compensator, is not shown in all 1946 rebuild info.


    Eric the Car guys videos show it, and so does RED 78'

    Quote Originally Posted by RED 78' View Post
    You can download them from my site.
    Here is the direct link.
    "http://myzephyrs.com/holly_carb_1946.htm"
    http://myzephyrs.com/holly_carb_1946.htm
    Jim's info is exceptionally good.


    This lack of proper detail info created a lot of trouble for many carb rebuilders.



    https://fordsix.com/viewtopic.php?f=1&t=75674

    Quote Originally Posted by xctasy
    Confirming the factory1978 1946 Holley diagram with what might be the right hookups for 1978-1979 T code 200's.

    1980-1982 B codes and 1983 X codes differ. Spark valve is in another place I think.




    Proper answer from Bob the builder,

    "Spark port on my Holley 1946 - manifold vs. ported vacuum"

    Post #8 by 62Ranchero200 » Tue May 29, 2012 "


    https://fordsix.com/viewtopic.php?f=...521947#p521947
    Quote Originally Posted by 62Ranchero200
    Quote Originally Posted by JackFish
    "Spark Port" is most definitely a ported source, not manifold.
    The photos in those pictures are labeled differently than the Ford manuals.
    I am currently running my dizzy off the "venturi vacuum port, works fine. There's is no discernible difference between that one and the EGR port on the passenger side. You can hook up a vacuum guage and compare to verify this.
    RPM at idle should not change when hooked up to ported vacuum or not.
    What is the timing with no vacuum to the dizzy?
    Tonight I hooked up a vacuum gauge to each of the three vacuum ports on my Holley 1946:

    "Spark" port - 15" at idle, 15" at 2000 RPM, staying at 15" as RPM increased further
    "EGR" port - 7.5" at idle, 15" at 2000 RPM, increasing slightly as RPM increased further
    "Venturi" port - 0 both at idle and at 2000 RPM

    I hooked up the DS II vacuum advance to the "EGR" port. Now it doesn't advance too far at idle, but it advances at higher RPM.

    Bob the Builder

    Picture?

    No one seasms to get the FoMoCo Duraspark II dual advance and three port vac 1946 Holley Carb hookup. The YFA has a different kind of hookup.

    Each 1-bbl carb has to have the right emissions hookups to work.

    Quote Originally Posted by xctasy
    oldie but a goodie for 1978-1979 T code 200's with the early Holley 1946

    ETCG Gets a New Car! -EricTheCarGuy 79 I6 Fairmont!

    https://www.youtube.com/watch?v=L22G...U14Vt7JJ_QSZvs





    Carburetor Rebuild Basics (Part 1): https://www.youtube.com/watch?v=85nszLpbbXY



    Carburetor Rebuild Basics (Part 2): https://www.youtube.com/watch?v=dprLQcQrAqE


    Carburetor Rebuild Basics (Part 3): https://www.youtube.com/watch?v=oRrJQRtBNck

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •