Car still having problems...
Thread Starter
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From: San Jose CA
Car still having problems...
Engine is very noisy @ 2500 rpm. Ticky sounding. Not like a bad engine, exhaust is just loud.
Will check plugs to see condition- could fuel fouled plugs cause the engine to surge like this? The car is really running like crap and it's getting on my nerves. The engine bucks between 1500-2000 rpm and off-idle response is crap.
I'm really getting depressed over here... the shop said they rebuilt the carb again... and got it running "good". This is not my definition of good.
-Steve
Will check plugs to see condition- could fuel fouled plugs cause the engine to surge like this? The car is really running like crap and it's getting on my nerves. The engine bucks between 1500-2000 rpm and off-idle response is crap.
I'm really getting depressed over here... the shop said they rebuilt the carb again... and got it running "good". This is not my definition of good.
-Steve
Melting Slicks
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St. Jude Donor '03,'11
Re: Car still having problems... (Pacin'California)
you didn't mention which carb you have. If its bucking its probably lean.
check to make sure your accelerator pump is working.
your power valve may be sticky use some carb cleaner on it.
check your cap and rotor for tracking and cracks
put a vacuum gauge on it to make sure you have good steady vacuum at idle. If its jumping around could be valve trouble. Do you know what a sticky lifter sounds like? tell us more about this sound at 2500 rpm.
[Modified by turtlevette, 7:17 PM 11/26/2003]
check to make sure your accelerator pump is working.
your power valve may be sticky use some carb cleaner on it.
check your cap and rotor for tracking and cracks
put a vacuum gauge on it to make sure you have good steady vacuum at idle. If its jumping around could be valve trouble. Do you know what a sticky lifter sounds like? tell us more about this sound at 2500 rpm.
[Modified by turtlevette, 7:17 PM 11/26/2003]
Thread Starter
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From: San Jose CA
Re: Car still having problems... (turtlevette)
It's not a lifter. The car had no problems before rebuilding the carb. (Don't ask what demon possessed me to do it...)
It's either carb or plug related...
It's either carb or plug related...
Thread Starter
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From: San Jose CA
Re: Car still having problems... (turtlevette)
I wonder if I should take it by them on friday or just forget about it... I don't wanna have to deal with the car being in a shop for so many days just for it to come back running like crap. Thinking about biting the $300 bullet and going to a different shop... to spend even more money. (groan)
Probably the carb though, huh?
-Steve
Probably the carb though, huh?
-Steve
Melting Slicks
Joined: Feb 2003
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St. Jude Donor '03,'11
Re: Car still having problems... (Pacin'California)
Probably the carb though, huh?
-Steve
-Steve
yea
you could buy a new carb for 300 bucks.
better yet you could have lars help you with you carb.
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From: The Only Corvette in Gila Bend, Az.
St. Jude Donor '09
Re: Car still having problems... (turtlevette)
Go get your money back, and also ask for a new set of plugs while your there. They hosed you bud, Don't let them get away with it...
Then call Lar's... :thumbs:
Then call Lar's... :thumbs:
Thread Starter
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From: San Jose CA
Re: Car still having problems... (turtlevette)
From what I last heard- lars is out of the biz. I'm tempted to try a local shop dedicated to rebuilding carbs. They have a flow bench and a bunch of various tuning machines.
I rebuilt the carb FIRST, before anyone else, using the carb body Nomad-78SA sent me. The throttle plate off my 17059507 carb was used as its linkage was necessary for my 700R4. I can't remember which metering rods I used, but the main jets for the 17058228 stayed in that carb body. Secondary rods and hanger were also from the 8228. When I rebuilt it, the car would stall out randomly.
I bought a recarbco carb but forgot about the tranny linkage, so had to send it back. Shop rebuilt this one for me and it still did not run right. (The point we are at now.) Before taking the 17059507 carb off the car, the engine ran good. Why mess with a good thing? In search of more power naturally... guess I bit off more than I can chew.
Would having the rods off ever so slightly cause it to bog this badly? It's like it's falling on its feet. It actually delivers good power in the upper RPM range, surprised me when I got into the secondaries @ about 45mph. It's just at off idle and cruise that it runs like crap...
-Steve
I rebuilt the carb FIRST, before anyone else, using the carb body Nomad-78SA sent me. The throttle plate off my 17059507 carb was used as its linkage was necessary for my 700R4. I can't remember which metering rods I used, but the main jets for the 17058228 stayed in that carb body. Secondary rods and hanger were also from the 8228. When I rebuilt it, the car would stall out randomly.
I bought a recarbco carb but forgot about the tranny linkage, so had to send it back. Shop rebuilt this one for me and it still did not run right. (The point we are at now.) Before taking the 17059507 carb off the car, the engine ran good. Why mess with a good thing? In search of more power naturally... guess I bit off more than I can chew.
Would having the rods off ever so slightly cause it to bog this badly? It's like it's falling on its feet. It actually delivers good power in the upper RPM range, surprised me when I got into the secondaries @ about 45mph. It's just at off idle and cruise that it runs like crap...
-Steve
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From: Las Vegas - Just stop perpetuating myths please.
Re: Car still having problems... (Pacin'California)
This is how you learn what makes things work Pacin is when you have to fix them. You are just to close to the chalkboard to see the problem. Step back and look at the shop manual or trouble shooting guide for a diagnosis. You may have to evaluate each little part in that Quadra thing. But it sounds like the previous shop mechanics that rebuild your carb are just turkeys.
Now you should get to know a local tuning shop if you have a good one available. Also the Carb Shop (http://www.customcarbs.com) down here by me in Ontario, CA. will rebuild and test run your carb to your engine specification for about $200. But myself am going to move to Holley speadbores (4175) due to simplicity and cost. They may not as sophisticated as a Quadra thing but will get the job done with fewer headaches. ;)
Now you should get to know a local tuning shop if you have a good one available. Also the Carb Shop (http://www.customcarbs.com) down here by me in Ontario, CA. will rebuild and test run your carb to your engine specification for about $200. But myself am going to move to Holley speadbores (4175) due to simplicity and cost. They may not as sophisticated as a Quadra thing but will get the job done with fewer headaches. ;)
Pro
Joined: Feb 2003
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From: Maplewood NJ
Re: Car still having problems... (Pacin'California)
Did you mess with your distributor at all? I had a bucking and surging problem and after I bumped my distributor over one tooth, that went away. But then again, my engine still isn't running right. I'd check to make sure your timing is set right. Couldn't hurt.
Or you could just switch to fuel injection. :D $300 for a carb that you're still going to have to tune and set up is crazy. A little bit more $$ and you can have a decent used TPI setup that'll give you better fuel economy and more low end torque from what I understand. Unless you really care about performace over 5000 RPM, it might be a good consideration.
Goodluck :thumbs:
Matt
Or you could just switch to fuel injection. :D $300 for a carb that you're still going to have to tune and set up is crazy. A little bit more $$ and you can have a decent used TPI setup that'll give you better fuel economy and more low end torque from what I understand. Unless you really care about performace over 5000 RPM, it might be a good consideration.
Goodluck :thumbs:
Matt
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From: Quebec
Re: Car still having problems... (comp)
It could be that your metering rod are not operating as they should. These rod inserts in the main jet when the vacuum is stronger than the spring of the power piston.
I.E. if the metering rod are too big, the engine will be too lean in cruise causing stumble. Combine that with a soft power piston spring and that would explain your off-idle bog. The best power piston spring for your engine is the 25 years old one that came with it or the exact replacement by the part number. I tried to change mine with an edelbrock kit and came back to the original one.
It could be that your secondaries opens too early too.
So IMO here's what they could have mess up:
Change metering rod diameter or main jet size (they are related)
Change power piston spring
Change power piston height adjustement
Secondaries opens too early(causing off-idle bog)
In all cases, I would look for a carb problem.
Good luck
Stephan
[Modified by American Boy, 3:10 PM 11/27/2003]
I.E. if the metering rod are too big, the engine will be too lean in cruise causing stumble. Combine that with a soft power piston spring and that would explain your off-idle bog. The best power piston spring for your engine is the 25 years old one that came with it or the exact replacement by the part number. I tried to change mine with an edelbrock kit and came back to the original one.
It could be that your secondaries opens too early too.
So IMO here's what they could have mess up:
Change metering rod diameter or main jet size (they are related)
Change power piston spring
Change power piston height adjustement
Secondaries opens too early(causing off-idle bog)
In all cases, I would look for a carb problem.
Good luck
Stephan
[Modified by American Boy, 3:10 PM 11/27/2003]
Thread Starter
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From: San Jose CA
Re: Car still having problems... (American Boy)
Is the secondary control in the air horn? If so, the secondaries are the same as the ones that were in the good working carb.
Also, I used the power piston spring and power piston from a carb that I know ran well. The only thing that is questionable to me is the metering rod...
Would a rod that runs too lean also cause the surging?
-Steve
Also, I used the power piston spring and power piston from a carb that I know ran well. The only thing that is questionable to me is the metering rod...
Would a rod that runs too lean also cause the surging?
-Steve
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From: Quebec
Re: Car still having problems... (Pacin'California)
Is the secondary control in the air horn? If so, the secondaries are the same as the ones that were in the good working carb.
Would a rod that runs too lean also cause the surging?
Too bad I live in Quebec 40 hours away, :seeya , I'd love to take a look.
Stephan
[Modified by American Boy, 3:35 PM 11/27/2003]
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From: San Jose CA
Re: Car still having problems... (American Boy)
How much is a plane ticket from Quebec? ;)
I have a feeling it's the rods myself, and I know how to change them, just don't have a bunch of rods laying around to play with. I'll stop it by a shop that's so equipped and have them check it out.
What are the odds that it's a bad rebuild? This carb's been through twice. I'm under the impression that it's tuning more than anything driving this dumb thing crazy!
-Steve
I have a feeling it's the rods myself, and I know how to change them, just don't have a bunch of rods laying around to play with. I'll stop it by a shop that's so equipped and have them check it out.
What are the odds that it's a bad rebuild? This carb's been through twice. I'm under the impression that it's tuning more than anything driving this dumb thing crazy!
-Steve
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From: Quebec
Re: Car still having problems... (Pacin'California)
I'm under the impression that it's tuning more than anything driving this dumb thing crazy!
BTW, I'll come by in my vette if you're willing to share the gas bill. :cheers:
Stephan
[Modified by American Boy, 2:20 PM 11/28/2003]
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From: San Jose CA
Re: Car still having problems... (American Boy)
40 hours, avg speed probably 55 mph... (you gotta be stuck in traffic whenever you aren't doing 100+, right?)
2200 miles... 183 gallons of gas.... $330... one way. Hm. I think I'll take it to the carb shop. :D Maybe next time!
2200 miles... 183 gallons of gas.... $330... one way. Hm. I think I'll take it to the carb shop. :D Maybe next time!
Pro
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From: Quebec
Re: Car still having problems... (Pacin'California)
Hey, you're pretty good in math....but I forgot to told you that I have the 100 MPG Super Q-Jet carburator. For 25$, I should be at your door. :troll :lol:
Anyway, good luck with your car.
Stephan
Anyway, good luck with your car.
Stephan