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I've got a 1973 Fleetwood, and some issues with fuel and air delivery. Some of the symptoms I'm about to describe make sense on their own, but the combination of them has me puzzled.

The car takes ~5 seconds to start with a cold engine. After start up, it will idle rough for a minute or so, and I have to feather the gas to keep it from stalling. I usually partially hold the pedal down for 10-15 seconds to get the rpms up and the engine warm. After it warms up a bit, the engine idles fine with no issues. During this process, I don't notice any abnormal exhaust coming from the tailpipe. Its a little dark, but not billowing black. After driving and after I turn the engine off, if I try to start the car within a few minutes of doing so, it usually fires right up. If I let it sit for ~10 minutes or longer, its even hard to crank than initial startup from cold. And if I'm out and about, every subsequent time I have to start the engine after letting it sit for more than 5-10 minutes, its harder and harder to crank, to the point where I get scared it wont start at all. At that point, when it finally does crank, I just drive straight home.

I think I need to rebuild the carb (never done it before, but I bought this car to work on). A new fuel pump/filter is prob a good idea too. It also is probably wise to make sure vacuum and fuel lines are sealed and clear. But I'd like to have some direction before going hog wild on new parts. So I'm hoping this combination of symptoms might ring a bell with some of yall? Thanks for the help.
 

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How are you starting it when cold? It won't start like a modern fuel injected car. You need to prime and set the choke. This is accomplished by pushing the gas pedal to the floor. This gives a shot of gas from the accelerator pump, and closes the choke. The choke closing will also set the carb on the fast idle cam. Try that, and get back to us.
 

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Right, I should have clarified. When I start it cold, I do pump the gas pedal twice. The guy I bought it from demonstrated that technique (because this is all new to me, but I'm loving learning). He pumped it twice, cranked it, and it roared to life and had a beautiful fast idle. He let it sit for 30 seconds or so, and then tapped the gas peddle and that set the idle to normal speed. It worked that way for a month or so after I bought it, but its changed over the last 6 months or so. But I should clarify, even it idles rough at startup, I can tell its idling fast. When I feather the gas to keep it from stalling, it drops the idle speed...and idles even rougher. But like I said, after a minute or so of letting it sit, the idle becomes stable. So it looks like the fast idle part at least is working like it should.

The previous owner said that he cleaned out the carb, but I'm not sure how much of a clean he did. He seemed like an honest guy that loved cars. But its never cranked as beautifully as it did in his garage. I cant fault the guy though, most of this car is original and I expected things like this to happen.
 

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....
The previous owner said that he cleaned out the carb, but I'm not sure how much of a clean he did. He seemed like an honest guy that loved cars. But its never cranked as beautifully as it did in his garage. I cant fault the guy though, most of this car is original and I expected things like this to happen.
I didn't read it all, but I guess you've ruled out going back and asking his insights RE: the change??? Lacking that option, it sounds like many "carbed old car off-idle miss" sorta symptoms.

Otherwise, I'm glad he had good luck flooring the gas twice when cold. I learned (maybe even read that many decades ago) that you set the pedal ONCE. It feeds the correct gas without flooding, and even more important it provides correct spring inertia according to the temp, up to and including full coil snap to slam the choke fully closed if cold enough. Hitting it the second time cancels the wind-up and the spring trying to unwind and you lose a notch for a combo of too much gas now and not enough choke.

It sounds like some heat-induced resistance issues going on with everything else. If it was me I'd suffer any criticism about throwing parts at it and do a COMPLETE dist. tune-up including ign. coil. (especially if original), emissions parts (EGR, PCV etc.), wires and plugs (if you can't prove them less than 8 years old), plus full round of ether on all the hoses and around the intake. Even check for blue spider webs at night. the full deal. It sounds like you've had the car 6 months - without a detailed maint. history you need an accurate baseline on condition of reg. maint. items.

It might just finally need a carb rebuild kit with the leather accelerator pump, and epoxied bowl fix.
 

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Prece the gas pedel only 1 time when starting cold.
It doesn't hurt to rebuild a carb.
But some of the cold starting problem may just be adjustments, a bad choke, or choke pull off.
In that case rebuilding the carb wouldn't be enough to fix it.
You really need to learn check, dignose, repair, & adjust basic carb settings.
If you want to do this yourself then buy at least 1 quadrajet book, watch some videos, and read online about them.
There is too many things to check & adjust to explain in a reply.
I wouldn't recomend trying to rebuild the carb until you figuere out the other problems.

The other issue:
" its harder and harder to crank, to the point where I get scared it wont start at all. At that point, when it finally does crank, I just drive straight home."
When you say hard to crank I think of the starter turning slowly.
Such as from overadvanced ignition timing, a starter, heat shield missing, or batery cables.

Where hard to start cranking normal speed but not wanting to start could be an entire list of possibilities.
A tune-up & general maintence is a good place to start.
 

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Time to check the distributor mechanical advance for binding. I've detailed it here several times in the past. Dunno how well the search feature might find it.
 

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I always do a full tune up when I buy a vehicle. I would always do a tune up before a carb rebuild. I could never get more than 2 years out of a set of points.
 

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You never know the tune-up condition unless you start opening things up.
At that point you may as well do a tune-up.
Exception would be oviously new parts.
At that I may verify it's the correct part.
Even with a new looking spark plug, I would pull em and check the gap.
Too many DIY don't even know to gap their plugs.
Little thiongs like that can make a big difference.

With older cars there is a lot of adjustments & maintence parts that wear fast by todays standards.
 

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Discussion Starter #9
If it was me I'd suffer any criticism about throwing parts at it and do a COMPLETE dist. tune-up including ign. coil. (especially if original), emissions parts (EGR, PCV etc.), wires and plugs (if you can't prove them less than 8 years old), plus full round of ether on all the hoses and around the intake.
Time to check the distributor mechanical advance for binding.
I would always do a tune up before a carb rebuild.
I would pull em and check the gap.
Hey guys! Thanks so much for the replies, sorry its taken me so long to respond.

To everyone pointing out I should only be pressing the gas pedal once...yall are right! Last week, I had some time to drive it around. I hadn't cranked it in ~2 months. I pressed the gas pedal once (all the way to the floor), and turned the key. After about 6-7 seconds of "eh-eh-eh-eh-eh-eh-eh," it fired up. And it DIDNT idle rough. It idled high and beautifully. I let it sit like that for ~2 minutes, and after I could tell the engine was warm (it just started sounding smoother), I tapped the gas pedal and the rpms dropped to a smooth low idle. So I guess I've just been priming it wrong and didn't know that.

Now I'm thinking the issue lies with getting it to fire up. It seems it idles fine if I prime it correctly (I'll drive it again this week to verify), and there definitely isn't something wrong with the starter motor. I can hear it turning consistently when I turn the key. So I feel like this is an ignition system issue.

I bought this car with the intent to work on it myself, and learn as I go. So in my mind, the next step is to check the spark plugs and properly gap them, and new distributor cap. If that doesn't fix the issue, I might as well replace the ignition coils (I'm a little daunted by that). Might as well do my fuel filter and PCV valve too. Do yall agree with this? This is all new to me, but I'm loving the process and appreciate yall's advice.
 

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Good hearing enough progress to allow focus on improvement(s). Unless there's some aftermarket update in your distributor, it's just an an old points-condensor-rotor-cap type, so replace it all at the same time. Don't shortcut or cheap-out on the expected normal total ign. tune-up. And it's got only one coil. Replace it too. Plugs and wires are periodic maint. items. Either prove they've been replaced within the period listed in the owner manual (or better in the FSM, or even google it), or even better 'Just Do It' by replacing them to remove those inexpensive variables from the mix as well.

Don't rule out the long initial start being carb related. As a test, shoot in starting fluid with a cold start. If it fires immediately then investigate carb wear and weak points further. Google 'Quadra-Jet problems' if your car is uses that brand.

You owe us a (some) pic(s) of this relic by now eh.
 

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Discussion Starter #11
Either prove they've been replaced within the period listed in the owner manual (or better in the FSM, or even google it), or even better 'Just Do It' by replacing them to remove those inexpensive variables from the mix as well.
I don't have any previous records (I thought I did, but they've seemed to go missing) so I'm just going to replace all these inexpensive maintenance parts and see how things look after that. Fingers crossed its not a carb issue! I'm also logging everything I do on the car.

I have the Factory Service Manual as well, and that has been awesome. I've already replaced the front shocks (going to do the rear ones soon) and removed/cleaned/oiled the power antenna, which works much better now.

Here's some photos. Besides a couple tiny rust circles on the body, its in amazing condition. Immaculate original interior.
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