Qjet choke question
Thread Starter
Burning Brakes
Joined: Jul 2001
Posts: 853
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From: Foxfield, Co
Qjet choke question
The choke on my qjet stays on way too long. takes about 15 min to unlock the secondaries. My exhaust crossover in my manifold has been reduced with smaller holes in the intake manifold gasket and my divorced choke just warms up too slow. I'm not worried about cold performance as I never drive in freezing weather. How can I adjust the choke to open up much sooner? I'd rather keep it and not just disable it.
Thanks.
Greg
Thanks.
Greg
Melting Slicks
Joined: Apr 2004
Posts: 2,083
Likes: 2
From: Montreal Qc.
Loosen the three screws and turn it in the direction of the "lean" arrow (clockwise I think) until it releases completely. I don't need a choke either, the only time I ever have to set mine up to work is the first start after winter storage.
**edit** sorry, thought he meant hot-air type choke. I defer to the master below
**edit** sorry, thought he meant hot-air type choke. I defer to the master below
Last edited by Star79; May 7, 2006 at 11:29 AM.
Tech Contributor
Joined: Aug 1999
Posts: 14,380
Likes: 6,391
From: At my Bar drinking and wrenching in Lafayette Colorado
Greg -
With the exhaust flow restriction on your crossover, you're stuck with a slow-responding choke. No good way to make that work the way it should with that mod. Just lock the choke wide open and put up with a few minutes of balkiness when cold. Bring it over and I'll show you how to lock it out.
With the exhaust flow restriction on your crossover, you're stuck with a slow-responding choke. No good way to make that work the way it should with that mod. Just lock the choke wide open and put up with a few minutes of balkiness when cold. Bring it over and I'll show you how to lock it out.
Tech Contributor
Joined: Aug 1999
Posts: 14,380
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From: At my Bar drinking and wrenching in Lafayette Colorado
Originally Posted by Star79
Loosen the three screws and turn it in the direction of the "lean" arrow .
Greg - The one thing you can do is see how "hard" the choke closes the choke when cold. If it's closing it pretty tightly, you can bend the choke rod so that the choke just barely fully closes when cold. This will shorten the choke application duration. But if the choke currently closes softly or just barely, there's not much to do with adjustment.
Last edited by lars; May 7, 2006 at 11:01 AM.
Thread Starter
Burning Brakes
Joined: Jul 2001
Posts: 853
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From: Foxfield, Co
Hi Lars, nice to hear from you again. Sitting in my garage currently 65* the choke is closed pretty tight so I think I will try to bend the rod a little, or if your going to be around this morning I wouldnt mind a nice drive up to Lafayette and you can show me how to disable.
Thanks
Greg
Thanks
Greg
Drifting
Joined: Sep 1999
Posts: 1,970
Likes: 91
Don't know what year you have but my 70 350 has the exact same problem. I have the crossover blocked and no heat riser in the ex. manifold. Talk about a looong time to warm the choke.
Expanding on Lars suggestions I found that there is a, I'll call it a assist spring,(2), attached to the vacuum break and choke lever. I've seen this spring attached to the slot in the vacuum break as in the photo,(1) and also just resting on the lever,(4).
I found that with the spring attached to the vacuum break slot,(1), it closes ,(assists),the choke in closing quickly and completely. The fast idle operates perfect. However, with it attached here it takes more that 10 minutes for the heat to overcome the coil and open the choke.
With the spring attached to the lever ,(4),it actually has no tension since it's attached to the same piece. I leave it this way because it doesn't close the choke quickly or completely. It takes a few cranks to start and runs rough for a bit,(lack of fast idle), but the choke opens within a few minutes.
Roes q-jet book has the spring on the lever(4). I've seen it on the vac break slot a bunch of times. Can't get an answer where it should be. (no luck at NCRS either).Maybe Lars has the answer/ explanation
Tech Contributor
Joined: Aug 1999
Posts: 14,380
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From: At my Bar drinking and wrenching in Lafayette Colorado
Greg -
On your setup, you can snip off (remove) the coiled spring around the choke pulloff lever arm. This will make your choke duration shorter and it will prevent your choke from snapping closed when the engine is hot after hot shut-down. This often improves drivability on the '72 choke setups.
Lars
On your setup, you can snip off (remove) the coiled spring around the choke pulloff lever arm. This will make your choke duration shorter and it will prevent your choke from snapping closed when the engine is hot after hot shut-down. This often improves drivability on the '72 choke setups.
Lars
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Instructor
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Originally Posted by lars
Greg -
On your setup, you can snip off (remove) the coiled spring around the choke pulloff lever arm. This will make your choke duration shorter and it will prevent your choke from snapping closed when the engine is hot after hot shut-down. This often improves drivability on the '72 choke setups.
Lars
On your setup, you can snip off (remove) the coiled spring around the choke pulloff lever arm. This will make your choke duration shorter and it will prevent your choke from snapping closed when the engine is hot after hot shut-down. This often improves drivability on the '72 choke setups.
Lars
Warren
Thread Starter
Burning Brakes
Joined: Jul 2001
Posts: 853
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From: Foxfield, Co
Originally Posted by lars
Greg -
On your setup, you can snip off (remove) the coiled spring around the choke pulloff lever arm. This will make your choke duration shorter and it will prevent your choke from snapping closed when the engine is hot after hot shut-down. This often improves drivability on the '72 choke setups.
Lars
On your setup, you can snip off (remove) the coiled spring around the choke pulloff lever arm. This will make your choke duration shorter and it will prevent your choke from snapping closed when the engine is hot after hot shut-down. This often improves drivability on the '72 choke setups.
Lars
Greg.
Melting Slicks
Joined: Mar 2006
Posts: 2,465
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From: Orange Park Fl
I have found one of the most satisfying mods on an old q-jet can be a manual choke. That conversion is particularly easy with a divorced choke; just run the cable and hook it to the existing mechanism! No permanant modification and a choke that works perfectly all the time for $10! What's not to love! God bless, Sensei
Melting Slicks
Joined: Mar 2006
Posts: 3,456
Likes: 102
From: Piedmont Va
St. Jude Donor '11-'12-'13,'19-'20
I have the opposite problem. I changed my intake recently to a edelbrock performer. The choke worked great on the cast iron unit. I installed the spring and rod assembly on the the intake, and now the choke stays wide open. (The rod is always forcing the linkage to full open position.) The choke worked good with the old intake. I think I'm gonna try and adjust it by bending the rod this weekend. I agree with the current weather it won't be much of a problem but when fall come's around i will want it working.