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Discussion Starter · #1 ·
Hello everyone, I'll preface this by saying I love the forum and its been a great aid in some maintenance I've performed since getting my dream car. I own a 1977 Lincoln Mark V (460 engine obviously) and it has the stock Motorcraft carb on it. I purchased it in August and the carb was rebuilt by a local "old-timer" mechanic who supposedly worked on the vehicle for years for the previous owner(s).

Car started great and ran great all summer, however there was a morning in maybe September in which it was freezing (around 30 degrees) and when I went to start the car it was very hard to start. Eventually after cranking it and following the procedure per OE Manual it started up and ran fine... Didn't run into the issue again and of course thought nothing of it (young and dumb perhaps). Anyways, now that its getting cold as heck out of nowhere here in Ohio I am preparing to put the car away for winter storage. But the hard starting issues are back... same as the incident in September. Hard start but eventually the engine will fire up and will run fine. I'd like to get it sorted out as I would like to regularly start the car while its in storage and move it around from time to time to keep the tires from getting bald spots.

I'm a young guy and this is my first carbureted car so I'm learning as I go. After searching this forum and many other information outlets I've learned quite a bit more about carbs beyond my previous very basic understanding, let alone my specific carb and its operation. Anyways, I observed that when I press the gas pedal to the floor and release it to set the choke, the plate snaps back from it but leaves a considerable gap still. I'd reckon around maybe .2-.25". From my understanding the plate is supposed to close just about shut when initially setting the choke before attempting start up, then upon ignition the choke pull off opens it up a bit. I've set the choke thermostat cap to the "index" setting as that is the recommended setting on the valve cover label, it was previously set to the leanest setting, but I haven't really messed with it past that.

I was wondering where I should begin looking/tinkering as to resolve this issue? I suppose it could be a fuel delivery issue, but my best bet at the moment would be the choke plate not snapping shut. I can imagine there could be tons of things, and very well may be beyond my ability but I would still like to try my hand. I can certainly ask my neighbor who is very proficient with cars, especially older ones, but I would like to learn. Plus I don't like to "bother" him if i can help it.

Thanks in advance and I appreciate any help. I'll answer any questions to the best of my ability as well!
 

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HI,
Just might have to readjust it,, Can you push (with your finger) the choke butterfly closed all the way? if yes then look at the linkage see if there is a bent rod on it holding it from going all the way closed Or adjust the choke to where it closes all the way (but not tightly). does the choke brake work?
you may have to readjust the fast idle as well once you get it sorted out..

good luck take care be safe
tim
 

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Starting a carbureted vehicle requires some finesse. Before jacking with the choke adjustment try pumping the pedal several times to get some fuel into the intake.

On vehicles with no choke you would sometimes have to pump the accelerator 5+ times and them modulate it as the engine starts tapping the pedal to keep a bit of accelerator pump shot going until things stabilize.

It is not uncommon on that series carb to have accelerator pump issues.

Look down the primary side of the carburetor with the choke open and cycle the throttle several times looking for the pump shot.
If there is none you've found your problem.








Scotty J. "AKA" The "Mad Porter"
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Ported BBF iron head specialist & Aluminum heads from all sources.
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See our products in the Vendor for sale section
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I’ll leave the hard starting comments to other guys but I will comment on starting the engine frequently while in storage for the winter. I live in MI and personally I don’t do that. Unless you get the the engine up all the way up to operating temperature you’re just going to introduce more moisture into the oil and exhaust system. If you’re that worried about flat spots on the tires go to Harbor Freight and buy 4 cheap jack stands to put the vehicle up on.
 

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The 4350 can be a bit "finicky" in some regards. Get a shop manual for the vehicle and "read all about it". I've got one on a 1976 F-250 with the 460 engine. The multiple pumps of the accelerator may help to overcome a choke that isn't doing quite what it should. On mine I was never able to hit that "sweet spot" where the choke is all closed on a cold engine and all open on warm engine. So, I installed a manual choke and throttle. It has never started so well and ran so well as since I made the conversion. But the driver needs to know how to properly handle the manual choke.
 

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Discussion Starter · #6 ·
HI,
Just might have to readjust it,, Can you push (with your finger) the choke butterfly closed all the way? if yes then look at the linkage see if there is a bent rod on it holding it from going all the way closed Or adjust the choke to where it closes all the way (but not tightly). does the choke brake work?
you may have to readjust the fast idle as well once you get it sorted out..

good luck take care be safe
tim
I played with it a bit last week one day. It’s been bitter cold and I’ve family in town so I’ve been busy of course, but planning on looking at it more tomorrow as I’m off work and the weather is supposed to be somewhat better.

I did mess with it a bit… it seems like there is some resistance. I’m not sure what I did but in between me moving the butterfly valve and pulling on the throttle, the choke plate snapped shut…. I went to start the car. Fired right up. The choke pull off works as well as I immediately got out to see if it opened it up slightly, which it had.

The following day though the issue remained. I went to set the choke and it didn’t move. I’m thinking I have a “hang up” somewhere. I’m gonna get some carb cleaner and clean up moving parts. I’m also going to check the little brass counterweight in thermostat housing as I’ve read about them binding up….

That or I dunno if the fast idle cam isn’t dropping? I’m not sure of the function of it but I’m reading up on it.

I appreciate the reply Tim.
 

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Discussion Starter · #7 ·
The 4350 can be a bit "finicky" in some regards. Get a shop manual for the vehicle and "read all about it". I've got one on a 1976 F-250 with the 460 engine. The multiple pumps of the accelerator may help to overcome a choke that isn't doing quite what it should. On mine I was never able to hit that "sweet spot" where the choke is all closed on a cold engine and all open on warm engine. So, I installed a manual choke and throttle. It has never started so well and ran so well as since I made the conversion. But the driver needs to know how to properly handle the manual choke.
Yeah I’ve deduced over reading various forums that they’re a mystery at times lol

I’ve seen people had just went with Manual chokes. I don’t really want to just because I don’t want to mess with the interior of the car.
 

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Yeah I’ve deduced over reading various forums that they’re a mystery at times lol

I’ve seen people had just went with Manual chokes. I don’t really want to just because I don’t want to mess with the interior of the car.

What many folks do is switch out that odd ball spread bore intake for an earlier std pattern OR a later truck intake with the holley pattern and EGR plate.
This opens up your carb replacement choices.
There is NOTHING that will fit on that Holley pattern spread bore intake.





Scotty J. "AKA" The "Mad Porter"
"EMC 2006" 3rd place finisher
Ported BBF iron head specialist & Aluminum heads from all sources.
Custom ground cams
See our products in the Vendor for sale section
Customized crate engines
ParklandAutoMachine.com
R-H-P.biz
"Parkland Performance Auto Machine" Formerly RHP
(253)-988-6648
Parkland Auto Machine
 

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HI ,
YOu can always make the choke close/richer by adjusting the choke but getting it open all the way may be a problem, May be a bent rod on the buttterfly...
What I would do is get it to full running temperature and bend the rod so it is fully open. then set the choke so it goes closed when its cold and the choke brake opens it like 1/8 to 1/4 inch. and it should open all the way when warmed up.. try that

good luck take care be safe
tim
 

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HI, Just an addition to my above.. the rod on the choke butterfly is kinda bent anyway and sometimes it can get straighten and is suppose to be bent.. so bending it shouldn't be a problem.... the cam that the rod is attached to by the adjustment spot can only hang straight down ... so if the cam is hanging with the rod straight down at the bottom, the only way to make the butterfly open more is to bend the rod.. Had to do that once on a carb before so it would open all the way when warmed up..

good luck take care be safe
ttim
 

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Ummm, just a heads up from a guy who used to do carbs a long time ago for a shop. The guy who tought me how to do it also tought me a trick on em. If you've got a fresh rebuilt carb, or you've blasted it with brake cleaner or carb cleaner, mist down the linkage with some WD-40.. All that linkage you just blasted super clean now has no lubrication for it to move and operate the way it was supposed to and will hang up/be sticky on you. If I remember correctly a 3/32 or a 1/4 drill bit (can't remember) is what you need to set how far you need the choke plate to close. Yes you need to pump it a few times for it to crank, but do you also get a stumble with it on the road when you give it the beans? If so that stumble could be a weak accelerator pump which is what you are using when you pump the gas a cpl of times to start it.. Well I know you're getting "flooded" with info on your carb (lol) so I'll hush... 😁
 

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Discussion Starter · #12 ·
Ummm, just a heads up from a guy who used to do carbs a long time ago for a shop. The guy who tought me how to do it also tought me a trick on em. If you've got a fresh rebuilt carb, or you've blasted it with brake cleaner or carb cleaner, mist down the linkage with some WD-40.. All that linkage you just blasted super clean now has no lubrication for it to move and operate the way it was supposed to and will hang up/be sticky on you. If I remember correctly a 3/32 or a 1/4 drill bit (can't remember) is what you need to set how far you need the choke plate to close. Yes you need to pump it a few times for it to crank, but do you also get a stumble with it on the road when you give it the beans? If so that stumble could be a weak accelerator pump which is what you are using when you pump the gas a cpl of times to start it.. Well I know you're getting "flooded" with info on your carb (lol) so I'll hush... 😁
I’ll take note of this! Makes sense. As for the pump, I haven’t had any issues when I’ve really given it gas. Gets on the highway just fine. But I’ll double check…. My neighbor is gonna take a look at it with me Wednesday if I can’t figure it out before then.
 

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Hello everyone, I'll preface this by saying I love the forum and its been a great aid in some maintenance I've performed since getting my dream car. I own a 1977 Lincoln Mark V (460 engine obviously) and it has the stock Motorcraft carb on it. I purchased it in August and the carb was rebuilt by a local "old-timer" mechanic who supposedly worked on the vehicle for years for the previous owner(s). Car started great and ran great all summer, however there was a morning in maybe September in which it was freezing (around 30 degrees) and when I went to start the car it was very hard to start. Eventually after cranking it and following the procedure per OE Manual it started up and ran fine... Didn't run into the issue again and of course thought nothing of it (young and dumb perhaps). Anyways, now that its getting cold as heck out of nowhere here in Ohio I am preparing to put the car away for winter storage. But the hard starting issues are back... same as the incident in September. Hard start but eventually the engine will fire up and will run fine. I'd like to get it sorted out as I would like to regularly start the car while its in storage and move it around from time to time to keep the tires from getting bald spots. I'm a young guy and this is my first carbureted car so I'm learning as I go. After searching this forum and many other information outlets I've learned quite a bit more about carbs beyond my previous very basic understanding, let alone my specific carb and its operation. Anyways, I observed that when I press the gas pedal to the floor and release it to set the choke, the plate snaps back from it but leaves a considerable gap still. I'd reckon around maybe .2-.25". From my understanding the plate is supposed to close just about shut when initially setting the choke before attempting start up, then upon ignition the choke pull off opens it up a bit. I've set the choke thermostat cap to the "index" setting as that is the recommended setting on the valve cover label, it was previously set to the leanest setting, but I haven't really messed with it past that. I was wondering where I should begin looking/tinkering as to resolve this issue? I suppose it could be a fuel delivery issue, but my best bet at the moment would be the choke plate not snapping shut. I can imagine there could be tons of things, and very well may be beyond my ability but I would still like to try my hand. I can certainly ask my neighbor who is very proficient with cars, especially older ones, but I would like to learn. Plus I don't like to "bother" him if i can help it. Thanks in advance and I appreciate any help. I'll answer any questions to the best of my ability as well!
I would get another carburetor.My Dad bought a 77 F250 when I was 7 years old.It had a stock Motorcraft carburetor.The previous owner had wired the 4 barrel shut..When I was 16 and started driving it I naturally wanted the 4 barrel working.When you hammered down the engine would miss, sputter and cut out.Everyone I talked to in my hometown said to take it to Albert Fulbright who was an older man that was an expert on carburetors.He rebuilt it, it did the same thing.He worked on it several times and never could get it to work.To my knowledge that was the only carburetor that he couldn't figure out.I replaced it with a Edelbrock and it did just fine.
 

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I just wanted to say, carbs need you to step on the pedal to let choke reset. The cams on the linkage need you to move them so everything can reset, it's little notches that need things to move. They do not start or act like injected vehicles at all. A few, two maybe three pumps seem to help at first try also. once running it should settle down and idle. maybe even pull itself down off the idle cames as it warms up. The Ford carbs had a problem with fuel leaking out a plug in bottom of carb, and causing the float bowl to go empty and needing a few cranks to refill. These things have a personality, all the old ones anyway. Like older Harleys
 
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