Choke Pipe Function On Q-Jet ?
Thread Starter
Le Mans Master
Joined: Jul 2009
Posts: 6,647
Likes: 1
From: East Aurora N.Y.
St. Jude Donor '10
Choke Pipe Function On Q-Jet ?
Does the choke pipe and choke hose enable the choke to operate properly ? Starting the car is becoming an adventure lately. If it doesn't start on the 1st try I'll have to floor it to start it and then feather the pedal for a bit...Once it's warmed up, it will run as advertised. I'm going to get the carb rebuilt over the winter , but I think I may just have a choke problem....I found the choke hose to have a slit in it the long way so it is apparently compromised.I'll fix that tomorrow , but any info would be appreciated.....
Safety Car
Joined: Apr 2000
Posts: 3,802
Likes: 61
From: Wichita KS
The choke pipe and hose was for the old thermalquad carburetors. You should not have one on your C3.
Yours should have a choke coil mounted on the intake manifold with a rod connecting it to a lever on the airhorn for the airflap (butterfly) and a choke pulloff vacuum pot.
At least that's the way early C3's are.
cc
Yours should have a choke coil mounted on the intake manifold with a rod connecting it to a lever on the airhorn for the airflap (butterfly) and a choke pulloff vacuum pot.
At least that's the way early C3's are.
cc
Last edited by CCrane65; Aug 9, 2009 at 01:32 AM.
Thread Starter
Le Mans Master
Joined: Jul 2009
Posts: 6,647
Likes: 1
From: East Aurora N.Y.
St. Jude Donor '10
The choke pipe and hose was for the old thermalquad carburetors. You should not have one on your C3.
Yours should have a choke coil mounted on the intake manifold with a rod connecting it to a lever on the airhorn for the airflap (butterfly) and a choke pulloff vacuum pot.
At least that's the way early C3's are.
cc
Yours should have a choke coil mounted on the intake manifold with a rod connecting it to a lever on the airhorn for the airflap (butterfly) and a choke pulloff vacuum pot.
At least that's the way early C3's are.
cc
Race Director
Joined: Nov 1999
Posts: 10,643
Likes: 8
From: Foxfield CO 1970 Convertible
When the engine is cold, and you look at the carb with the air cleaner off, is the choke closed? That's the easiest way to tell. It should snap shut when you touch the throttle a bit.
It sounds like the deteriorated pipe has made your choke non-functional.
It sounds like the deteriorated pipe has made your choke non-functional.
Melting Slicks
Joined: Oct 2005
Posts: 2,056
Likes: 8
From: Redruth Cornwall
When the car is cold, the choke will initially be open if it is operating correctly as the last time you used the car, it should have opened fully.
When you go to start the cold car, you should pump the throttle to the floor once to release the choke so that it will snap closed. She should then start.
As mentioned above, remove the air cleaner and check when cold after car has fully cooled from a normal working temperature. If the choke is open, manually move the throttle linkage and you should hear and see it snap shut. If not there may well be a problem with the choke mechanism.
The split in the pipe would possibly only cause slow warm up problems if I am thinking correctly....lol
Race Director
Joined: Apr 1999
Posts: 11,520
Likes: 13
From: CORVETTE 77 385 C.I. TEXAS
Besides fixing the hose, you may need to adjust the choke richer.
Thread Starter
Le Mans Master
Joined: Jul 2009
Posts: 6,647
Likes: 1
From: East Aurora N.Y.
St. Jude Donor '10
1) 1st the choke hose will be replaced
2) The choke pipe is in perfect shape.No deterioration.
3) I will cold check the choke as recommended by Jotto
4) As Ganey recommends,a richer setting may be in order.It is leaned way out....almost to the max.( I wonder why ? )
Thank you guys for the lesson in choke operation and your recommendations..I'll let you know how it turns out. .
2) The choke pipe is in perfect shape.No deterioration.
3) I will cold check the choke as recommended by Jotto
4) As Ganey recommends,a richer setting may be in order.It is leaned way out....almost to the max.( I wonder why ? )
Thank you guys for the lesson in choke operation and your recommendations..I'll let you know how it turns out. .
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Thread Starter
Le Mans Master
Joined: Jul 2009
Posts: 6,647
Likes: 1
From: East Aurora N.Y.
St. Jude Donor '10
The choke does close on a cold pedal pump, so that's cool.
NAPA opens at 10am so I have to wait to get vacuum hose.
I did adjust the lean/rich to 1 notch lean.It was almost pegged all the way lean, probably due to someone messing with it while it sat for 15 years w/o as much as a tune up.
Details to follow.
Racer
Joined: Jul 2009
Posts: 336
Likes: 1
From: Asheville N.C.
With air cleaner off notice that choke butterfly closes, when it starts, the butterfly should open about 1/4"(can use drill bit as a gauge) if is open more, then adjust the choke pulloff screw(I think turn it clockwise) until it reaches this measurement. It may take a couple of cool mornings to do it. Hope this works!!!!!!!!!ED
Instructor
Joined: Aug 2009
Posts: 112
Likes: 0
From: Caledon Ont
if you have or can borrow a vacume pump, you can apply vacume to the choke circuit and visualy see what the front flap is doing, it should also be riding on a fast idle cam that puts you in fast idle till the car warms, the line going into the manifold brings engine heat to the choke which causes the spring to expand and thus rotate the choke flap, if the line is clogged or sometime clogged at the intake manifold even a carb rebuild won't help you'll get the same problem...should check this first.
Thread Starter
Le Mans Master
Joined: Jul 2009
Posts: 6,647
Likes: 1
From: East Aurora N.Y.
St. Jude Donor '10
HOLY CRAP !!! What a difference ! Between riching the choke out to 1 mark lean and sealing both ends of the choke pipe with new vacuum hose, the thing starts up perfectly after 1 foot mash and then just turning the key.The fast idle is working fine and once the oil pressure is up, I get instant response from the pedal......I will however take ED79's advice and be sure the choke opens to 1/4 in....Too late now though, it's gotta cool down......When I turn the key when it's hot, it starts immediately, like 1/2 a crank....
THANK YOU GENTLEMEN !!!
THANK YOU GENTLEMEN !!!
Thread Starter
Le Mans Master
Joined: Jul 2009
Posts: 6,647
Likes: 1
From: East Aurora N.Y.
St. Jude Donor '10
.....This is just another step in getting a car back into perfect running condition starting with a battery,calipers & brakes, water pump , thermostat, harmonic balancer, etc. One thing follows another and I'm almost there.It rained after the initial test , but the sun is out now, so I haven't been able to take it out for a sufficient test beat yet.I can't wait until next summer when the suspension gets redone.Priorities...You know ?
Well....Time for the 1/4 " drill bit test!
Last edited by jeff79'; Aug 9, 2009 at 03:33 PM.
Thread Starter
Le Mans Master
Joined: Jul 2009
Posts: 6,647
Likes: 1
From: East Aurora N.Y.
St. Jude Donor '10
Man ...What a difference!...I'm loving it !...1 pedal mash on a cold start and Vrooom!....No pedal on a hot start and Vrooom!....Instant pedal response is back when it's all warmed up too....The choke opens a ch over 1/4" when cold started and she idles @ 6 hundo steady, cold or hot.BACK TO NORMAL !....Hmmm, I may not even need a carb rebuild....Thanks again boys !..
Last edited by jeff79'; Aug 11, 2009 at 07:13 PM.
Race Director
Joined: Apr 1999
Posts: 11,520
Likes: 13
From: CORVETTE 77 385 C.I. TEXAS
HOLY CRAP !!! What a difference ! Between riching the choke out to 1 mark lean and sealing both ends of the choke pipe with new vacuum hose, the thing starts up perfectly after 1 foot mash and then just turning the key.The fast idle is working fine and once the oil pressure is up, I get instant response from the pedal ....
When I turn the key when it's hot, it starts immediately, like 1/2 a crank....
THANK YOU GENTLEMEN !!!
When I turn the key when it's hot, it starts immediately, like 1/2 a crank....
THANK YOU GENTLEMEN !!!That's what some of us expect.
