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Discussion Starter #1
I'm starting to get the itch to work on the Cat again so... Back when I had the 302 running pretty good (before attempting to switch it to petronix) the only issue was getting it to kick down from fast idle. I have the original 4v which I had rebuilt. Can that circuit by the choke be replaced? I'm beginning to think I should just buy a new 4v with electric choke and put the original on the shelf until I am able to have her restored.

What do you think? If so what carb should I get for a stock 302 J code?
 

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Discussion Starter #2
Anyone? Beuller?
 

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What do you mean here, "Can that circuit by the choke be replaced?" ? I don't understand the question. There are replacement parts available for the choke. Or, something in the 500CFM range for a new carb would be good. I'm gonna say a Holley, but of course it's what ever you like.

http://www.summitracing.com/parts/HLY-0-80570/
 

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Well, you need to look at the step up linkage and see if there's a problem before you go replacing parts or going to another carb.
The choke is a fairly simple system.


Is everything hooked up or has a PO disconnected stuff, are things in disrepair, etc?
 

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Discussion Starter #5
I'm not sure what it is called but the linkage right in front of the choke sticks. If I manually move it the car would idle fairly well. Otherwise it would rev pretty high and that is why I nearly sideswiped my Jimmy as I kicked up rooster-tails. I'll get a picture of the area I'm talking about once I pick up my primary PC from the shop on Friday. I'm not so sure of the vacuum routing either even though I have the CD from WCCC. All this is sorta moot if I can't turn her over so I'll have to fix my screwup with the Petronix first.
 

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I assume you have a Ford 4300 4V with heat stove pipe installed from exhaust manifold. I think your piston in the choke housing is sticking. Clean it with 2+2 carb cleaner and if that does not do it, take it apart and clean the piston/bore by hand. Then adjust the spring on the choke so it just closes when cold or the choke will be on too long. I would also turn down the high idle screw which is adjustable when choke is on. I like my choke on just enough to start and then backing off very quickly. Hope this helps.
 

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What carb do you have? Autolite, Motorcaft, Holley? Got any numbers on the tag?
 

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I assume you have a Ford 4300 4V with heat stove pipe installed from exhaust manifold. I think your piston in the choke housing is sticking. Clean it with 2+2 carb cleaner and if that does not do it, take it apart and clean the piston/bore by hand. Then adjust the spring on the choke so it just closes when cold or the choke will be on too long. I would also turn down the high idle screw which is adjustable when choke is on. I like my choke on just enough to start and then backing off very quickly. Hope this helps.
Would you happen to have some pictures of choke housing, etc? I have a 4300 and I have to use starting fluid to start my car when it's cold. My choke doesn't really work at all and if this could fix it, I am willing to try.

Thanks,
Paul
 

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You have to have two things for easy cold start: fuel from the accelerator pump and the choke closed. Check for fuel squirts when moving throttle in the carb opening. If not there, the carb needs a new rubber cup on the accelerator pump rod. If OK, check the choke by removing choke housing cover and clean/inspect the choke piston action. That 4300 is a good carb, rebuild kits for it are cheap. Take the top off (release I think one choke rod) and your almost done. The air horn will pull the accelerator pump rod and floats out. It is a tricky carb to service for the first time just because the rods attach to both the body and air horn, but once done, it will last for decades trouble free. Just do not take it apart more than needed, and use 2+2 carb cleaner to blow it out jets, idle screw circuits and air bleeds.
 

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Discussion Starter #11
I picked up my PC today so within the next couple of days I'll get a photo posted.
 

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Discussion Starter #12
Lightly used some steel wool to get the oxidation off the hood and then polished as best I good.

As promised here is the area I am talking about.


 

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Discussion Starter #14
Here you go:



 

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That's a Motorcraft 4300 alright. I'm going to gather some 'specs' for you and pm them to you. Just looking at the pictures I see a few things that need attention. 1) the accelerator lever may not be set correctly, typically the pivot should be in the center hole of the three. 2) the choke plate is completely closed, shouldn't be. 3) It appears that the vacuum tube at the front right corner of the carb base doesn't have a vacuum hose connected to it, vacuum leak. If you hold the throttle open, you should be able to freely move the choke linkage open and closed with your hand. If you can't, check for binding of the bent linkage rod, if thats ok then check the choke piston and linkage. You may have to remove the disk from the bottom of the carb base to properly clean the piston cylinder. This carb is a 'bugger' to get set properly but when it's done right this is a great carb.
 

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I think TC has you covered! I can offer the appropriate cuss words if you feel the need after your first try...! ;>) They are mother hummers to set up...
 

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One other thing to check:

Your carb uses heated air, rather than an electric element, to heat the bi-metallic spring that opens the choke. The way the system is supposed to work is that the heated air rises through a steel tube from a small chamber cast into the passenger side exh. manifold. This tube has an asbestos insulating sleeve on it.
The air to be heated is drawn through a different, non-insulated steel tube, that attaches to a fitting on the carb.
It isn't uncommon to see a blockage somewhere in the system that keeps air from flowing and reaching the choke housing. Its also fairly common after 40+ years for the hot air tube to simply rust off at the bottom, and not be connected to the manifold at all. Either way, heated air doesn't get to the spring, and the choke doesn't de-activate as it should.

OK, and yet another I thought of as I was typing. With some choke housings, it is possible to install the choke spring backwards. As it heats up, it actually tries to close the choke tighter. Not likely your problem, since it sounds like it does kick-off eventually. But if you remove the spring for any reason, be sure to mark its orientation so that it goes back in the same way.

Good luck!
 

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Discussion Starter #18
You are correct that the tube was so rusted it just broke in half, in fact it was "fixed" by using some rubber tubing.
I ordered a new one from WCCC last year and replaced it but I didn't know about the asbestos. When she was running the issue didn't seem to be the choke but that linkage just behind it.
 

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That's a Motorcraft 4300 alright. I'm going to gather some 'specs' for you and pm them to you. Just looking at the pictures I see a few things that need attention. 1) the accelerator lever may not be set correctly, typically the pivot should be in the center hole of the three. 2) the choke plate is completely closed, shouldn't be. 3) It appears that the vacuum tube at the front right corner of the carb base doesn't have a vacuum hose connected to it, vacuum leak. If you hold the throttle open, you should be able to freely move the choke linkage open and closed with your hand. If you can't, check for binding of the bent linkage rod, if thats ok then check the choke piston and linkage. You may have to remove the disk from the bottom of the carb base to properly clean the piston cylinder. This carb is a 'bugger' to get set properly but when it's done right this is a great carb.
Tomcat, you certainly have eagle-eyes on this one! I have a 68 Autolite 4300 partly disassembled on my bench, and I'm comparing to Cougar_is_Grr8's photos. On mine, the stovepipe from the exhaust manifold enters into the center of the black thermostatic choke housing. Cougar_is_Grr8's seems to be a newer model Motorcraft, that would need a different stovepipe arrangement (unless he's got a newer exhaust manifold to match). Please correct me if I'm mistaken!
 

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You are correct that the tube was so rusted it just broke in half, in fact it was "fixed" by using some rubber tubing.
I ordered a new one from WCCC last year and replaced it but I didn't know about the asbestos. When she was running the issue didn't seem to be the choke but that linkage just behind it.
Did you order this part from WCCC? http://www.cougarpartscatalog.com/mct008.html If so, I'm thinking you'd really have to bend this tubing around to make it work on your carburetor. But, I'm probably wrong on this and will be slammed by the experts!
 
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