Problems with Dad's '73, help please?
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Joined: Jul 2007
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From: Hartford County Connecticut
Problems with Dad's '73, help please?
So my pops has owned this 73 stingray since the year he drove it off the new car lot. It's a beautiful car, but I've rode in it maybe 3 times my whole life, and I'm 21. The problem is that it hasn't been running for the first 15 years of my life, we got it fixed, and it ran for a a few months and then it started to run really rich. My dad and I in an effort to fix it replaced the carborator to no avail and then gave up on it for a while as we dont have the time or the money just to send it into the shop to get fixed again. I'm no mechanic, but I'm willing to learn to fix this beauty for by Dad. If anyone has some advise on what might be the cause of this, it'd be greatly appriciated.
Racer
Joined: Aug 2006
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From: Wellington, New Zealand
You should post some details in your user profile (where you live etc). I'm sure there would be a local guy that could lend a hand or some advise, most Corvette people are more than willing to help a fellow owner.
Melting Slicks
Joined: Aug 2002
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From: Midland TX
Did you buy a replacement carb or put on another used one?
Carbs are pretty simple if they are the right one for your car and don't have trash in the seat or float.
Have you checked the timing, points, plugs, etc.?
Carbs are pretty simple if they are the right one for your car and don't have trash in the seat or float.
Have you checked the timing, points, plugs, etc.?
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Joined: Jul 2007
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From: Hartford County Connecticut
The carb was a purchessed new replacement carb, so it should work fine and the installation seemed pretty easy and fool proof. I am going to check to spark plugs, but I beleive when we had the car fixed, it was an overhaul tune, so I'm sure the guy replaced the plugs, seeing as though he's a reputable corvette mechanic. Timing and points? I beleive I understand what you mean by timing, as in the belts and such. But what are points?
Melting Slicks
Joined: Mar 2006
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From: Connecticut
Wrong jets/primary rods and many many more problems are very common.
Do a search on "rebuilt Quadrajet" and it may enlighten you.
I seriously hope you didn't trade the original in for the core charge.
If it was not a QJ, what was it?
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From: Hartford County Connecticut
Thanks for the definition bodawg, i can tell you know what you're talking about, and that helps alot. Ever think of working for Marion Webster?
To be honest, I'm not sure what the carborator is, and I'm not going to check until tomorrow, as it's 2:30 am where I am, but I'll let you know. If I know my pops I can make a guess and say it'll be as close to the original as possible in model and make. And we do in fact have the original. My dad will hang on to every stock part that ever comes off that car, and I can't blame him (I'll get him a mount for the stock small block for when I replace it with a hotter small block, but he doesn't know about that yet. I have to save up).
As for the points and spark plugs, I checked and there's no way they need replacing. The timing might be the problem, so I'm going to check that asap. Asside from plugs, points, and timing, is there anything else I could check for?
Once again, I appriciate the help gents. It's nice to see so many folks that share my appreciation for Vettes.
To be honest, I'm not sure what the carborator is, and I'm not going to check until tomorrow, as it's 2:30 am where I am, but I'll let you know. If I know my pops I can make a guess and say it'll be as close to the original as possible in model and make. And we do in fact have the original. My dad will hang on to every stock part that ever comes off that car, and I can't blame him (I'll get him a mount for the stock small block for when I replace it with a hotter small block, but he doesn't know about that yet. I have to save up).
As for the points and spark plugs, I checked and there's no way they need replacing. The timing might be the problem, so I'm going to check that asap. Asside from plugs, points, and timing, is there anything else I could check for?
Once again, I appriciate the help gents. It's nice to see so many folks that share my appreciation for Vettes.
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From: Hartford County Connecticut
Okay, I checked, and it is indeed a rebuilt quadrajet carb. However, would this really be the problem? because the Vette was exhibiting alot of the same problems with the original carb. Perhaps we were just unlucky and had to replace the old carb and got a poor quality new one, so as the effect was the same?
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Melting Slicks
Joined: Mar 2006
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From: Connecticut
Okay, I checked, and it is indeed a rebuilt quadrajet carb. However, would this really be the problem? because the Vette was exhibiting alot of the same problems with the original carb. Perhaps we were just unlucky and had to replace the old carb and got a poor quality new one, so as the effect was the same?
Not many get lucky with a rebuilt QJ unless it was rebuilt and tuned by a professional, rather than a company that rebuilds them and sells them at auto parts chain stores.
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From: Hartford County Connecticut
well I'm not absolutely sure about the timing, I'm checking that next. If I recall the last time I was in the vette (what, 6 years ago now?) I noticed that there were vibrations in the engine at around 75 miles an hour. It's obviously an engine balancing problem of some kind, but could that also alude to the timing being off?
Also, we still have the old quadrajet. So if we got unlucky with the new one, is it possible to take the old carb apart and check for refuse in the seat or float? Or would that be better left to a professional? From what I hear, Quadrajet's are monsterously complicated. I wonder if they have an assemebly diagram of the carb in the vette manual.
By the way, beautiful ray you got there bob onit. The 73's one of the best looking vette's out there in my honest opinion.
Also, we still have the old quadrajet. So if we got unlucky with the new one, is it possible to take the old carb apart and check for refuse in the seat or float? Or would that be better left to a professional? From what I hear, Quadrajet's are monsterously complicated. I wonder if they have an assemebly diagram of the carb in the vette manual.
By the way, beautiful ray you got there bob onit. The 73's one of the best looking vette's out there in my honest opinion.
Last edited by heirloomvette73; Jul 6, 2007 at 03:49 PM.
Melting Slicks
Joined: Mar 2006
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From: Connecticut
Just be sure everything else checks out first, timing, points, plugs ect.
Last edited by Bob Onit; Jul 6, 2007 at 04:05 PM.
Melting Slicks
Joined: Mar 2006
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From: Connecticut
If its been sitting for a long time the fuel system may be all gunked up
Smell the gas in the tank, if its bad then it needs to be drained.
Maybe someone will pop in with a method on how to clean or flush the tank and line if it needs it.
Good luck.
Smell the gas in the tank, if its bad then it needs to be drained.
Maybe someone will pop in with a method on how to clean or flush the tank and line if it needs it.
Good luck.
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From: Hartford County Connecticut
The engine also need's balancing. I guess back in the old days they didn't do a very good job of balancing engines. Luckily for me we live in the computer age. So with this in mind, does anyone out there know how much money an engine balancing job will run me? As I mentioned before, one day I'm going to buy the hotter small block option for it, so I'm trying to weigh the prices.
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From: Hartford County Connecticut
OH... good point lyle. I hadn't honestly thought of that, though it makes alot of sense. The poor vette was in park for a very long time. Man, you guys are helpful, and thanks for the luck, I'll need it. If it's bad gas or rust, that'd certainly be the more fundimental problem.
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From: Hartford County Connecticut
I looked into the gas issue. everything appears to be fine, though I'm sure we need to get the tank pumped again. Evidently, the vette's been running rich since it's 5th year of life. My dad had hoped that the fellow in manchester would have fixed the problem when he went over the car again, but I guess he didn't. So this has been a problem since about 1978. Does that ring any bells for anyone?
Melting Slicks
Joined: Aug 2002
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From: Midland TX
I bought a rebuilt Q-jet from Auto Zone and it works fine on my 72 454. It did not have the orig Q-jet when I bought it and did not have any PN stamped in it. No one knew what it was for so I just traded it in for a new one.
You could have a vacuum leak - but that would make it run lean - wouldn't it?
A vacuum leak could cause your engine to run rough as you mentioned.
You say your Vette runs rich. How are you determining that it is running rich?
Did you pull the spark plugs to see if they are wet or fouled?
Is it blowing alot of black smoke?
Carb cars will have more of a gasoline smell than newer FI cars. Are you just smelling gas from the car?
You could have a vacuum leak - but that would make it run lean - wouldn't it?
A vacuum leak could cause your engine to run rough as you mentioned.
You say your Vette runs rich. How are you determining that it is running rich?
Did you pull the spark plugs to see if they are wet or fouled?
Is it blowing alot of black smoke?
Carb cars will have more of a gasoline smell than newer FI cars. Are you just smelling gas from the car?