Choke problem
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From: In The Blue Ridge Mountains
Choke problem
I have a Holley 4V on my 351W and whenever I start it, I have to hold the trottle down for about 2 minutes befor it will idle on it's own. I replaced all the ignitial stuff and have a new air filter but it still does the same thing. I checked the choke and it's closed when cold and open when hot. I hate to admit it, but I'm a German Fluel Injected kinda guy and don't really know what to start with. Now what?
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From: In The Blue Ridge Mountains
With all the hoses on this thing, vacuum is certainly something to look in to. I guess I have to buy that vacuum checker after all.
Is there a chance that the plunger type thing with a vacuum hose connection (that is not connected )could be causing this too? I don't know what it is because, once again, the Haynes manual doesn't mention it. The part slides up to push the accelerator so I can only assume it's supposed to do what I have to do now manually. That being slightly push the accelerator until the engine warms?????
Is there a chance that the plunger type thing with a vacuum hose connection (that is not connected )could be causing this too? I don't know what it is because, once again, the Haynes manual doesn't mention it. The part slides up to push the accelerator so I can only assume it's supposed to do what I have to do now manually. That being slightly push the accelerator until the engine warms?????
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From: Rose City, MI
well if the choke butterfly opens and closes on its own i dont know why its not working right, as long as u pump hte pedal once befor turning the key on it should work fine. my choke doesnt operater so i am going ot convert it to manual on monday when i am off work. Might want to try a choke conversion kit from automatic to manual. an easy way to check for vacume leak is use wd 40, carb and throttle body cleaner, or starting fluid but use spareingly...
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From: Virginia
On the passenger side of the carb, there is a linkage hooked to the choke plate that is connected to a fast idle cam. When the choke is closed, the cam holds the throttle open for fast idle. As the choke opens, the cam slowly lets the throttle down to idle. And there is an adjustment screw for how fast the fast idle is. It rides on the cam.
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From: In The Blue Ridge Mountains
I didn't think about that fast idle cam. That may be it. I read where the fast idle on this engine is supposed to be 1600 rpm so If the coke is working then that probably is what's up.
I still wish I could ID that plunger thing on the driver side of the carb though. I think it may be the deceleration valve and/or part of the cruise control system.??
"easy way to check for vacuum leak is use wd 40, carb and throttle body cleaner, or starting fluid but use sparingly..."
Please explain this procedure. I'm not sure what the WD40 would do for checking vacuum? Remember, I'm a Bosch Fuel Injection kinda guy
The last time I worked on a carb was in the early 80's and it was on a BMW.
I still wish I could ID that plunger thing on the driver side of the carb though. I think it may be the deceleration valve and/or part of the cruise control system.??
"easy way to check for vacuum leak is use wd 40, carb and throttle body cleaner, or starting fluid but use sparingly..."
Please explain this procedure. I'm not sure what the WD40 would do for checking vacuum? Remember, I'm a Bosch Fuel Injection kinda guy
The last time I worked on a carb was in the early 80's and it was on a BMW.
Last edited by jfgte8296; Oct 12, 2003 at 07:21 AM.
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From: In The Blue Ridge Mountains
Originally posted by Franklin2
On the passenger side of the carb, there is a linkage hooked to the choke plate that is connected to a fast idle cam. When the choke is closed, the cam holds the throttle open for fast idle. As the choke opens, the cam slowly lets the throttle down to idle. And there is an adjustment screw for how fast the fast idle is. It rides on the cam.
On the passenger side of the carb, there is a linkage hooked to the choke plate that is connected to a fast idle cam. When the choke is closed, the cam holds the throttle open for fast idle. As the choke opens, the cam slowly lets the throttle down to idle. And there is an adjustment screw for how fast the fast idle is. It rides on the cam.
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From: Virginia
You are right, you need to set the fast idle when the choke is closed, so the screw will be sitting on the cam. The fast idle screw will do nothing after the engine is warm. Thing of it is, these things usually never need adjustment, unless someone has fiddled with it. I would make sure that everything is working first. If you want to play with it after the engine is warm. make a mark on the round black choke housing, and the metal part of the carb. Then loosen the three screws holding the round black housing, and turn it in the "richer" direction. Eventually, the choke plate should try to close. It should not close all the way till you kick the throttle of the carb. Why? Because the choke will be hung up on the fast idle cam, and kicking the throttle will let the fast idle screw ride up on top of the cam. Make sure you put the round black choke housing back where it was, or you may decide you want more or less choking action, in which case turn it a little to the "richer" direction or the "leaner" direction
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From: In The Blue Ridge Mountains
Well this is a rebuilt carb so its possible that setting was not readjusted. What direction is the richer one? The choke doesn't have any marking on it. I didn't think I would have to actually move the whole choke. I did do that on the old POS Chevy though so I guess that should work. It had markings on it.
That little (nearly impossible to get to) screw does what then? Isn't that supposed to increase and decrease the amount of accelerator "push" when the choke is working? I just bought the shop manuals for the truck from a guy in California. In a week or so, I should have even more help, I hope.
That little (nearly impossible to get to) screw does what then? Isn't that supposed to increase and decrease the amount of accelerator "push" when the choke is working? I just bought the shop manuals for the truck from a guy in California. In a week or so, I should have even more help, I hope.
Last edited by jfgte8296; Oct 12, 2003 at 09:24 PM.
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