Rebuilding quadrajet right now -
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Rebuilding quadrajet right now -
Hi, sorry for the time sensitive nature, in the middle of rebuilding a quadrajet that has been bogging out and fuel coming from somewhere.
Upon removing the air horn section, it looks like two pieces are missing from this YouTube video I'm following. Are they crucial to proper performance? Don't know if they sell at online vendors or not... Pictures below, thanks.
Black cup in his hand near the float
Black plastic piece in guys hand that appears to hold the float in?
I replaced the accelerator pump separately a few months ago, and is still bogging.
Lastly, it was recommended to use JB weld on the plugs on the under side of the carb. I have a very hard time starting the car if it's been sitting for a week, so I'm guessing the plugs are leaking. Anyone have a better recommendation than JB?
Thanks a million
Upon removing the air horn section, it looks like two pieces are missing from this YouTube video I'm following. Are they crucial to proper performance? Don't know if they sell at online vendors or not... Pictures below, thanks.
Black cup in his hand near the float
Black plastic piece in guys hand that appears to hold the float in?
I replaced the accelerator pump separately a few months ago, and is still bogging.
Lastly, it was recommended to use JB weld on the plugs on the under side of the carb. I have a very hard time starting the car if it's been sitting for a week, so I'm guessing the plugs are leaking. Anyone have a better recommendation than JB?
Thanks a million
Le Mans Master
Joined: Jul 2006
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From: charlotte north carolina
The plastic part that holds the float is absolutely necessary! Without it the entire float and it's lever arm will rise and unseat the fill valve. That's what's (probably) causing the bog-it's flooding the engine. The other piece is a spacer for a diaphragm that was used in some carbs (I think). I don't think that it's needed.
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Thanks for the replies, especially on the plastic float cover. As amazing luck would have it, I went to the glove compartment and the previous owner had a ziploc of parts. The plastic part was in there haha. Whew. Saved sourcing that.
Drifting
Joined: Jul 2011
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From: Syracuse NY
Wow. Ive had a screw or two leftover after Ive torn apart an entire interior......but extra carb parts? (and major parts at that)...but to have the ***** to put it back together AND keep the extra parts in a bag...
BUBBA OF THE YEAR contender right there. Please contact the previous owner and let him know he's the recipient of this prestigious title.
BUBBA OF THE YEAR contender right there. Please contact the previous owner and let him know he's the recipient of this prestigious title.
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Hahaha I will! The plastic cup thing wasn't there but the float cover was. I thought it was some sort of clip from the dashboard or something that fell off in the back. Lo and behold, tried putting in the carb... Fit right in. I assume he put the carb back together, had an extra part and didn't know where it went, put it in the bag.
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Thanks everyone for the quick replies on this. The good news is that my first quadrajet rebuild was a success, took some time but I lovingly redid the whole thing. The bogging has stopped when it's cold. However, it's got a serious bog when it's warm, and I've included a video at the bottom. Is there a thread anywhere about adjustments to make for operating temperature?
The only 2 I know of is that my choke thermostat spring is set dead center which could be adjusted, and the choke rod that goes from the top choke valve down into a linkage (with two holes), I put the rod on the outside hole. I don't want to just start shooting in the dark on guesses, any ideas or advice? Thanks again.
Youtube video of ok cold start, bogging when warm:
Completed:
The only 2 I know of is that my choke thermostat spring is set dead center which could be adjusted, and the choke rod that goes from the top choke valve down into a linkage (with two holes), I put the rod on the outside hole. I don't want to just start shooting in the dark on guesses, any ideas or advice? Thanks again.
Youtube video of ok cold start, bogging when warm:
Completed:
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It wasn't terribly dirty or rusty to begin with (California car), but definitely needed a good cleaning. Had some Brakleen lying around to start, and finished with a professional degreaser. I used to do auto detailing and had some left over, can't remember the brand name but something similar to this:
http://www.chemicalguys.com/Grime_Re..._p/cld_104.htm
http://www.chemicalguys.com/Grime_Re..._p/cld_104.htm
Last edited by 1978BackToLife; Jun 10, 2016 at 06:32 PM.
Safety Car
Joined: Oct 2007
Posts: 4,383
Likes: 1,755
From: Seattle Area Washington
Loosen lock allen screw, Take spring pressure off the adjusting screw until the hook in the spring just touches the pin in the shaft. Then turn the adjusting screw 7/8 of a turn tighter. If a four speed car 1 turn. Looks like a auto car.
Last edited by bmotojoe; Jun 10, 2016 at 06:40 PM.
Race Director
Joined: Aug 2004
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From: Duvall, WA
You have to loosen the allen bolt first in order to be able to adjust the screw. Unscrew the adjuster so the rod on the screw is just touching the spring, without putting any pressure on it. Tighten the screw one full turn from that point, tighten the allen bolt and then re-test.
Race Director
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From: Duvall, WA
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I adjusted the spring tension as advised, seems to be about the same tension. Good lord... When I floored the throttle manually under the hood, at operating temp, it SHOT a burst out of the primary like a backfire and gave me a good laugh. It's bogging in neutral, operating temp, without load and without engaging the secondaries.
Last edited by 1978BackToLife; Jun 12, 2016 at 11:01 PM.
Le Mans Master
Joined: Jul 2006
Posts: 8,117
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From: charlotte north carolina
The secondaries will not open when the engine is revved in neutral. There isn't enough air flow to open the butterflies-unless you want to destroy the engine by holding the throttle open. I would turn the attention to the ignition system. Check timing, condition of cap, rotor and plug wire routing for crossed wires.
Team Owner
Joined: Jan 2006
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From: Crossville TN
Don't overlook the 'exchanged plug wire' thought. I've seen it happen and the engine just appears to run a little rough at idle. Re-trace each plug wire from the distributor to the plug. If they route through shielding, make sure you tug on each of those wires at one end to know which wire it is at the other end.
CHECK THIS FIRST!!!
Safety Car
Joined: Oct 2007
Posts: 4,383
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From: Seattle Area Washington
A couple of things.
1. Connect your hand held vacuum pump to the choke pull off and see if it holds a vacuum.
2. With engine off and at normal operating temp take a plastic drinking straw (I like the golden arches size straw) and drop it down the vent tube in the center of the carb and with a fine sharpie make a mark on the straw at the very end of the vent tube. Now with a little pressure pushing down on the straw push down until it feels like it's hits bottom (push straw in and let return a couple time to make sure there is no obstruction), make another mark on the straw in the down position. Now with the straw in the vent tube start your engine and see if the primary rod hanger is being pulled down to your second mark at idle.
If your choke pull off has not been modified there should be a slight delay as when the secondary's are allowed to open.
When you put the air horn gasket in place are you absolutely positive that the primary hanger arm-arms didn't bend at all?
1. Connect your hand held vacuum pump to the choke pull off and see if it holds a vacuum.
2. With engine off and at normal operating temp take a plastic drinking straw (I like the golden arches size straw) and drop it down the vent tube in the center of the carb and with a fine sharpie make a mark on the straw at the very end of the vent tube. Now with a little pressure pushing down on the straw push down until it feels like it's hits bottom (push straw in and let return a couple time to make sure there is no obstruction), make another mark on the straw in the down position. Now with the straw in the vent tube start your engine and see if the primary rod hanger is being pulled down to your second mark at idle.
If your choke pull off has not been modified there should be a slight delay as when the secondary's are allowed to open.
When you put the air horn gasket in place are you absolutely positive that the primary hanger arm-arms didn't bend at all?
Le Mans Master
Joined: Apr 2011
Posts: 6,284
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From: Hermosa
On your "completed" photo of the carb it does not appear as though the accelerator pump lever is resting on top of the acclelerator pump shaft.
Insure that the accelerator pump is functioning properly.
Insure that the accelerator pump is functioning properly.