There are supposed to be a couple of "fingers" that stick out from the bracket to hold the choke pull off, but they are broken off of your carb. It's not that unusual for them to be gone. I've seen folks use a tiewrap to hold the CPO in place. Not real pretty, but it might work until you get around to doing something else. Larry T BTW, the long arm from the secondary air valve goes in the top slot of the CPO and the short arm from the choke (not there) goes in the bottom slot of the CPO.
I'll see if I can strap it down somehow. Here's what it looks like now: Also, every Quadrajet carb I'm seeing for sale new is 750cfm which as noted seems excessive.
HEY! Here's some good news for you! I think I just found your other throttle return spring. It's that blue spring that looks like somebody's rigged it up to maybe hold the choke valve open. Take it off and I'll bet you that it will just fit inside that other throttle return spring. You can thank me the next time that your throttle doesn't stick open! Then take a piece of mechanic's wire and figure a way to rig it so it holds the choke blade fully open. At least until you get some kind of a choke hooked up on it. Actually the second throttle return spring might also help to bring your idle speed back down where it belongs too!
You mention a slow, choking start. Besides the obvious problems with your carb, check battery connections, and also check your base ignition timing when you get the tune up and carb squared away. Too far advanced timing will cause slow, hard starts. just anotgher hing to put on the list to check.
It looks to me like your blue spring is hooked to keep you choke flap shut. The problem there is that the choke is completely missing on the carb and the only thing that's going to open the flap is the CPO and it probably doesn't completely open the butterfly. I think I would unhook the spring (and put it inside the bigger return spring as has already been mentioned) and see if the butterfly will completely open when the engine is running. The carb will run rich if it doesn't. And if you want the secondaries to work, you'll have to figure out a way of opening the catch on the secondary throttle shaft. It might open when you pull the spring, you'll just have to try it to see. The 750 is the smallest QuadraJet they make. It isn't over carbed like a square bore 750 cfm carb, because the primaries are about the size used on 450 cfm carbs and the flow comes from the Dominator sized secondary throttle bore. Your engine doesn't see the big flow numbers until the secondaries open up and the air valve doesn't open until the engine can use the additional flow. Your secondaries aren't opening at all, so I figure you have about a 200 cfm Quadrajet. I still think you probably need to think about a replacement when you can. The Summit 750 Quadrajet would work fine. Larry T
I was looking at the summit one and noticed the CPO and the choke are reversed on that one compared to the setup that would have been on the one I have. Does that make a difference? I'm going to pull the serial on the carb I've got tomorrow to figure out exactly what year/model it is but when it comes to replacing are all quadra jets made for chevy 350's mounted the same way or do I need to worry about looking for a specific application?
It's the second design quadrajet (started around mid to late 70's, I think) and it has a top of the later "electronic" series. It should have a round choke on the carb and not a divorced choke on the intake. As far as fit goes, they are pretty universal. The Chevy (and factory 429 Cobrajet ) had the fuel inlet pointing to the passengers side. The B/O/P & Caddys had the fuel inlet to the front. You shouldn't have any problems with the one you posted from Summit. Larry T
After you get your choke issue solved I think you should swap that PCV to the other side. right now your vacuum is pulling from a PCV valve on the same valve cover as the breather cap. Plug that one and connect vacuum to the one on the pass. side. That way it draws ALL the gasses across like All the factory PCV setups. Good luck-
Any chance you can dumb that down for me. Which hose to where? I put the spring over on the throttle so now it's doubled up as it should have been. It's starting better than it did previously but I think that is mostly because I filled up the gas tank and it's not straining to find the tiny bit that was left in the tank. I took the truck for a drive yesterday, it bogs a bit from a dead stop if I don't give it a good deal of gas. It also managed roughly 7mpg yesterday which doesn't make me happy given the performance. It's putting out a ton of black smoke and according to the wife smells horrible. From what little I understand this is an air fuel mixture issue but I'm not sure where to start in trying to address it (short of changing the carb completely - something I can't really afford right now).
is this guy being remotely accurate in getting the mixture screws setup right? http://www.youtube.com/watch?v=XRCUibTkm3o&feature=related
Hey Alden, I'm a recent convert to quadrajets, just replaced the edelbrock 600cfm on my '58 apache with one I rebuilt, didn't lose any power but picked up a few mpg. When they're properly set up they work fine. Yours is only a few parts away from being there. Do yourself a favor, write down the carb number (probably 1708XXXX) and identify what heads and mods your motor has then give Cliff a call at Cliff's High Performance. ( cliffshighperformance.com ) He'll sell you exactly what you need and give you advice over the phone. His website even has a forum you can post and ask questions on. Good luck! Art.
Thanks Art! Short of ripping the engine apart what can I do to identify if the engine has any modifications? I know it's got headman headers but beyond that I didn't really notice anything that seemed out of the ordinary.
I didn't read through all the replies, but you are also missing the top of the distributor cap. There should be a flat top with holes in it, that the little nob on top of each one of those plug wire snaps into.
Hey Alden, I was ordering a rebuild kit from Cliff, in order for him to get me the right jets and rods, he wanted to know everything about my motor, down to the cylinder head casting numbers. He literally would not let me place the order until he had the info, and I'm glad he did that, the carb fired right up and took minimal tweaking to get perfect. Since you're probably just going to need an electric choke conversion and the associated pull off parts just give him a call, he can talk you through it. You can even email him pics, I did when I had questions. He can also explain to you why a 750 cfm quadrajet works fine on everything from a 283 to a 396, something about the secondaries sucking just what they need. Anyhow, I'm really happy with my q-jet. Tonight I'm rebuilding the edelbrock performer on my '64 Riviera. I was really hoping to find a spreadbore intake under it so I could run a q-jet on that too. Cheers, Art.
Alden, if you haven't already sorted your issue let me know. I can get you a complete carbon to swap on to isolate if that's the only issue.
Oh that would be awesome. The truck is driveable as it sits so I could bring it your way if you would be free at all. The wife has just sworn she won't come along for a ride in the truck until it's sorted out due to the smell.
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