I recently purchased a 58 Apache with a 1973 350 already swapped in. Once it's started and running it eventually warms up and seems to run fine but when being started it frequently fires (a very slow kind of choking start) for a second then stalls. Sometimes it takes 3-4 attempts to get it to stay running. I am a self described idiot when it comes to diagnosing issues so I was hoping someone here might be able to help me out. I understand these had an automatic choke but I noticed at least one part near the carb was not attached and was wondering if that was the choke and if that was why it was having issues starting when cold. Any thoughts? Thanks! -Alden
The choke pull-off cannister has come uncrimped from its mounting bracket on the side of the carb. Though I guess it hardly matters as I don't see any linkage going to any sort of a choke thermostat anyway. I hate to suggest it, but this looks like a good candidate for a manual choke conversion. Geez... I can't believe I just said that.
Are the universal conversions any good or should I look for one specific to this carb? Referring to the carb, this may be one of the dumbest questions ever asked here, but can someone tell me what carb I've got so I can look to see if there's a specific choke setup available?
Well what you've got there is a QuadraJet, but I'd be hard pressed to say whether or not it's the exact right one that would have come on a 1973 350. It really shouldn't be an issue for getting a manual choke kit though. And maybe it's just me but I wouldn't feel bad about getting a better accelerator return spring setup on there too. Either a little heavier spring or a dual, inner and outer style spring like what was probably on it originally.
No offense intended but a good place to start is a tune up. If your choke is squirreled up you can overcome that by pumping the hell out of it but it sounds like a good place to start would be a general tuneup.
Well, it appears that the choke isn't hooked up an the diaphragm that keeps the secondary air plate closed when it should be is broken. That is what Claymart referred to as the choke pulloff. At least two cobbled up things that both contribute to the condition you are experiencing. You can figure out what carb you actually have buy taking the number of the side of the body and either posting it for someone to check out or checking it out on online on a Qjet site. Those carbs work great when they are in good shape but tend to act up when you are not.
Hey no offense taken, I am looking for any and all advice so it's definitely appreciated. The tune-up is on the short list since I don't know the maintenance history of the truck.
Not related to your problem, but some folks are dead set against using that kind of fuel filter, especially if it's a glass one. A hard bump against that valve cover hold down bolt could break it, and at that point you may not have to worry about cold starts.
Been there done that the phrase it'll be a hot time on the old town tonight comes to mind. I have had a lot of old chebys that the choke didn't work, once the timing etc is right they will be a little cold natured but they will still start and run.
I'm sorry to play the dummy but I've been looking for a manual choke kit and all I can find anywhere is the eldelbrock ones that summit sells and they don't seem to be geared toward a quadrajet. I have a factory cable for my 58 apache but beyond that I'm not sure what I'd need to get. Is there a kit for this specific carb? Honestly I'd rather just go with a stock setup with the automatic choke but all I can find are replacement choke thermostats but that assumes I have the rest of the choke setup and I'm not finding that anywhere unless I snag a whole used carb off ebay.
Whats with the spring hooked on to the choke linkage ? Doesn't look to be any gas in the filter and does the carb still have the internal filter in it ?
Never liked the quadrajet choke setup , but to get it to stay running I would have a friend work the ignition and manually operate the choke by using the disconnected linkage , after it warms a bit use some mechanics wire to hold it into the full open position and see if it will idle . A carb rebuild or replace is in your future , but this may be able to pinpoint it as your problem . Also the intake has an EGR block off plate , so you may have issues trying to get a "choke stove" to attach correctly . You may want to go for an earlier intake manifold too .
Fix the above two mentioned and also check those little black block off caps they tend to dryrot and leak air,
Start with a good tune up. Make sure you have a full 12 volts going to the HEI. also get rid of the little fuel filter , they have been known cause problems... and add one more spring to the throttle return just to be safe.
your vacuum pot is detached from its mount and as a result the now twisted linkage cannot work properly.... do you see?
The vacuum for the dashpot is connected to the right front port in Swazzie's picture. Isn't the right side port normally for distributor vacuum advance? I know that, in 1973, they threw all kinds of vacuum valves on these motors so they might have routed it through somewhere else too.
I see enough wrong with the carb, that I think I'd look for a replacement. Like, why does it have a later model top on it? Choke and secondary air valve diaphram FUBAR. I think I'd find a carb that has an electronic choke that didn't look like it was put together out of the spare parts bin and go from there. But that's just me. Larry T
Some good info and some bad info. LarryT has it right. Buy a replacement from Summit with an automatic choke. Stay away from a used unit from Ebay. Missing parts are just part of the problem. I know...they're pricey. The down side of messing around with an old unit is the cost in dollars and the frustration of after everything you do to make it right it still won't work.
That should work, but you really dont need a 750 cfm carb for a 350 motor. Somewhere around a 600 or 650 should be more than enough for your motor. And it might be a few bucks cheaper too.
It appears to me you have an older vintage carb. I notice the electric choke connector near the separated vac diaphragm. Manual choke would be a budget fix.
If you can find one with a manual choke it might be cheaper, too. I second Smiliessafari on not getting a used one. I bought a rebuilt carb from a carb rebuilder online and when my engine was running like shit, it was one more thing to suspect. It turned out that the carb was perfect, but it would have been nice to know from the get-go that it wasn't the carb.
I hooked everything up the way you have it in your picture and it fired right up and idled properly (albeit maybe a little high but when I put it in gear it dropped to a normal idle immediately). My remaining issue for the short term - I will still look into a new carb - is that the vacuum pot is loose. is there a way to tighten it in place, will a new choke pull-off fix that or is there another piece I'm missing that I just don't see in your picture? Napa has them for $15 but if it won't change anything I don't want to just waste my money - part # CRB 24785 Thanks!
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