Topic: Rebuilt Carb and New Vacuum Hoses Now Will Not Start
in Forum: C3 Engines
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Good Evening Guys! Hope this post isn't too long. I'm too descriptive when I write. It's kind of my thing...
Good day with my C3 today! Cleaned manifold and valve covers (Simple Green and water). Came out kind of blah, but better than it was :) Let it sit over an hour in the open air and was very meticulous with drying any "pools" of water.
Installed rebuilt Quadrajet. Checked fuel filter and reinstalled (gasket-spring-filter with opening to fuel line).
Changed out many vacuum hoses with new red ones. During that process, while removing an old hose, a male plastic end broke off. Not sure exactly what it is for, or what the repercussions of it not being connected are. See the pic with screwdriver pointing to broken male end.
After all new lines were connected, I'm left with two open ends and can't remember where they go. I know. Dumb. See pic I'm holding the "T".
The last pic is of a large open port near the AC on passenger side. I believe this one was not connected prior to me taking everything apart. Any idea what that is for?
Finally, at the end of the day, reconnected battery, tried to start and got nothing. Engine turns and turns but will not start. Tried pumping accelerator and nothing. Didn't want to flood out so I stopped. I haven't adjusted any mixture screws yet (have to look up how to do that) and was wondering if that could by why she wont turn over.
As always, any help is appreciated!!
"You know, we always called each other goodfellas. Like you'd say to somebody: You're gonna like this guy, he's all right. He's a goodfella. He's one of us. You understand?"
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Open the choke plate and look down in the carb then open and close the throttle a couple of times. If you see fuel spray inside the carb the fuel supply is working. If not you may have the filter in backwards or fuel has not pumped into the carb yet. How long did it sit disassembled? The pics are a bit hard to make out. Fine close up but too close to tell what I'm looking at. Could you back off a bit and try a few more shots? That will give some prospective to what is there. Then I can help a bit more.
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The first pic is of the TCS solenoid. The REAR port of that solenoid goes back to the vacuum advance canister on the distributor. The port sticking out to the side(the broken one) is a vent. There would normally be a small square piece of foam to act as a filter on that port. I can see a small bit of foam still on there. The FRONT port should go to full time vacuum on the carb. It looks like you may have that line on correct, but I think the "Tee" fitting you have should be in that same line from the carb to the solenoid, and tees off to the smog pump.
The large fitting in the last pic is for the hose connections to the smog pump from the exhaust diverter valves. The passenger side hose is on there, as seen in the 2nd pic, just under your hand.
As far as it now not starting, I'm with Ken...prolly don't have any fuel in the carb. I would start by removing the fuel line going into the carb, then removing the fitting on the carb itself, and check to see that filter is correctly installed. The open end of the filter should be facing the fuel line. There should be a spring behind the filter, on the carb side, to hold the filter against the inlet fitting. SO...unless you disconnected some wiring somewhere, or you've left one of the large vacuum lines loose/connected to the wrong place, I'd think your no start has to do with the carb itself.
|UPDATED|6/29/2015 9:43:07 AM (AZT)|/UPDATED|
The large fitting in the last pic is for the hose connections to the smog pump from the exhaust diverter valves. The passenger side hose is on there, as seen in the 2nd pic, just under your hand.
As far as it now not starting, I'm with Ken...prolly don't have any fuel in the carb. I would start by removing the fuel line going into the carb, then removing the fitting on the carb itself, and check to see that filter is correctly installed. The open end of the filter should be facing the fuel line. There should be a spring behind the filter, on the carb side, to hold the filter against the inlet fitting. SO...unless you disconnected some wiring somewhere, or you've left one of the large vacuum lines loose/connected to the wrong place, I'd think your no start has to do with the carb itself.
|UPDATED|6/29/2015 9:43:07 AM (AZT)|/UPDATED|
Joel Adams
C3VR Lifetime Member #56 
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Thank you for the reply!
I took additional, wider angle photos. I hope these are better! Added notes to the photos, too, to help show what I'm referencing. Looking at my assembly manual is not as clear cut as I would have hoped.
I took additional, wider angle photos. I hope these are better! Added notes to the photos, too, to help show what I'm referencing. Looking at my assembly manual is not as clear cut as I would have hoped.
"You know, we always called each other goodfellas. Like you'd say to somebody: You're gonna like this guy, he's all right. He's a goodfella. He's one of us. You understand?"
20152515373r.jpg)
Here's a pic from my 73, it's an L-82 4 speed car so there are a few minor differences, but I think it may help.
P.S. - please forgive the unpainted bolt heads on my intake and t-stat housing, just R & R'd them and have had a chance to touch them up yet.
|UPDATED|6/29/2015 1:19:12 PM (AZT)|/UPDATED|
My smog pump has been removed for rebuild and my TCS switch is slightly different than yours. My input is in the front of the switch like yours but my output to the dist. vacuum advance is out the side where your vent appears to be. My vent is out the back where you see the yellowish plastic wire connector.
So here's how my connections run - looking from the front of the carb. Top right small hose goes to the Evap cannister down in the fender, the large middle hose below the fuel line input goes to the PCV valve on the valve cover then down to the cannister. In your last pic above, you have the large PCV connection right, but there is a small black hose at the bottom of the pic with a white stripe that should go to the top right of the carb. The larger black hose right next to it at the bottom of your last pic comes from the drivers side injector tube off the exhaust manifold and goes to the large hole you point out at the back of the smog pump.
My next connection is the small black hose that goes from the top left of the carb to the from of the TCS switch. This is where yours should have a T in the line and that second connection should go to the diverter valve on the smog pump.
My next connection is another small black hose that goes from the very bottom left corner of the carb (my choke pull off covers the view of that connection) and that goes to the EGR valve.
The last connection is on the left hand side of the carb, (which i believe is plugged off in one of your original pics) directly to the choke pull off. I think you have one too many T's in your system right behind smog pump.
The only other issue is the broken off vent connection at the TCS switch. Mine has a foam filter inside that yellowish connector and no vacuum line hooks to it. I would think that if yours is only a vent, you could glue or somehow strap a piece a foam to filter air that gets sucked into the vent.
Look for further input from Joel and Kstyer, but as far as no start, I doubt if vacuum lines have too much to do with that. It should start but might run really rough if you have a major leak or two. You need three things to run - gas, spark and compression. I would say either gas, spark or both are your no start issues.
P.S. - please forgive the unpainted bolt heads on my intake and t-stat housing, just R & R'd them and have had a chance to touch them up yet.
|UPDATED|6/29/2015 1:19:12 PM (AZT)|/UPDATED|
John Sigmund
valkman57@sbcglobal.net
NCRS Member 61302
NW NCRS Chapter Member
Duct tape is the new Black !!
This is GREAT information! Thank you, guys. I'm grateful for the detailed feedback! Your under hood pic helps a lot!
I can say for certain, I installed fuel filter correctly...triple checked it after reading horror stories online: first, plastic gasket, next spring, last filter with opening facing line.
I researched TCS solenoid and it seems a lot of C3 owners bypass this setup. Maybe I'm not in bad shape after it broke after all?
Having difficulty seeing the difference between EGR and choke pull off. From the pics it looks like they're the same thing?
I let too much time go between removing carb and hoses and reinstalling...forgetfullness set in. Wife and kiddos are keeping me busy today but I WILL be back under the hood later this week (cannot wait!). I plan on taking my laptop under the hood and double check my work against all of your input and pics. Thank you Adam for the design sheet!
I can say for certain, I installed fuel filter correctly...triple checked it after reading horror stories online: first, plastic gasket, next spring, last filter with opening facing line.
I researched TCS solenoid and it seems a lot of C3 owners bypass this setup. Maybe I'm not in bad shape after it broke after all?
Having difficulty seeing the difference between EGR and choke pull off. From the pics it looks like they're the same thing?
I let too much time go between removing carb and hoses and reinstalling...forgetfullness set in. Wife and kiddos are keeping me busy today but I WILL be back under the hood later this week (cannot wait!). I plan on taking my laptop under the hood and double check my work against all of your input and pics. Thank you Adam for the design sheet!
"You know, we always called each other goodfellas. Like you'd say to somebody: You're gonna like this guy, he's all right. He's a goodfella. He's one of us. You understand?"
You're right, the TCS switch Is easily bypassed, just go directly from the carb to the dist. and leave the TCS disconnected. Put a T in that line if you still want or need to hook up the diverter valve on your smog pump. The other two connections are also very simple, bottom front vacuum outlet on the carb to the EGR valve and that outlet you have blocked off on the passenger side of the carb goes directly to the choke pull off. I'm sure it will make a whole lot more sense when your under the hood. Drop us a line when you get there. Good luck !!
John Sigmund
valkman57@sbcglobal.net
NCRS Member 61302
NW NCRS Chapter Member
Duct tape is the new Black !!
Ok Guys I am 99% sure I now have everything installed correctly. Your posts helped a lot...thanks again! I owe you guys some beers! 
The only thing that concerns me is the vacuum line coming off of the vacuum advance unit on the distributor. Originally, that line ran to the male end that snapped off on the TCS solenoid, what you guys are calling the filter. Can you explain the consequences of not having that line connected?
EGR Valve vacuum line goes to the BOTTOM LEFT male end on carb. (I believe they call it the ENG PIPE (Engine Pipe?)). Which leaves the only remaining open vacuum line, that line coming from vacuum advance unit.
The only open PORT remaining is the large open one on the smog pump (3rd picture in my last post). I am certain this was not connected when I bought the car.
The only thing that concerns me is the vacuum line coming off of the vacuum advance unit on the distributor. Originally, that line ran to the male end that snapped off on the TCS solenoid, what you guys are calling the filter. Can you explain the consequences of not having that line connected?
EGR Valve vacuum line goes to the BOTTOM LEFT male end on carb. (I believe they call it the ENG PIPE (Engine Pipe?)). Which leaves the only remaining open vacuum line, that line coming from vacuum advance unit.
The only open PORT remaining is the large open one on the smog pump (3rd picture in my last post). I am certain this was not connected when I bought the car.
"You know, we always called each other goodfellas. Like you'd say to somebody: You're gonna like this guy, he's all right. He's a goodfella. He's one of us. You understand?"
Jason, go back and re-read the second paragraph below my pic in my original response. In your third pic you show the open port, but you also have two black hoses at the very bottom of the pic, what are they hooked to ?? The larger one goes to the large open port you are asking about. The smaller black hose comes from the evap canister and should be hooked to a vacuum port on the front/right of the carb. Now the big question, did you get it running ??
John Sigmund
valkman57@sbcglobal.net
NCRS Member 61302
NW NCRS Chapter Member
Duct tape is the new Black !!
Ok. Let's chalk that one up to I'm a dumb a$$ 😳
You were absolutely right. There was a vacuum hose that was supposed to go to the large open port. When I removed the carb and hoses I tucked the large hose away...too well apparently because I overlooked it a dozen times. Re-read your post, went back under the hood and found it! It is now reconnected.
To answer your question...GOT HER STARTED!!!
I sprayed some starter fluid into carb and she fired right up! Let her run a while, shut her down and she fired right back up. Decided it was time for a drive and she drove great! Idles rough. I'm guessing that's because the mixture screws are off. Tried adjusting the screws according to a few videos I watched, but I did not notice a difference in idle hardly at all. Adjusting those screws is not easy. Car sounds nice from behind though!
"You know, we always called each other goodfellas. Like you'd say to somebody: You're gonna like this guy, he's all right. He's a goodfella. He's one of us. You understand?"
in Forum: C3 Engines
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