Last post on Jan 25, 2011 at 11:39 PM
You are in the Classic Cars - Archived Discussions
This discussion is ARCHIVED. To reactivate the discussion, post a request in the Lost In The Town Hall... discussion.
What is this discussion about?
Fuel System, Performance Mods, Engine, Fuel System, Coupe, Convertible, Hatchback, Truck, Sedan, Wagon
#1 of 399 Carburetor Problems On Older Cars
by MrShift@Edmunds HOST
May 04, 2005 (11:28 am)
This forum is for discussing the care and feeding (and fixing) of problems related to carburetors, those primitive and extinct devices found on most cars 15 years or older.
#2 of 399 Re: Carburetor Problems On Older Cars [Mr_Shiftright]
May 05, 2005 (5:07 am)
I rebuilt a mid-seventies Quadrajet a couple of months ago. The Q-jet is actually a very elegant design; you can calibrate cruise, mid-range, and full throttle mixture to a very precise degree. The people who bad mouth them simply don't understand how and why the Q-jet operates the way it does.
May 05, 2005 (8:50 am)
Carburetors work quite well when properly set up and adjusted, which is like HARDLY EVER....congratulations on getting it right. I think the big fuel dragsters all use carbs don't they?
Many the reason they were abandoned is that a computer can't control them very well---you have to use mechanico-electrico-vacuumo devices and these get all whacked out--not stable enough for emissions requirements.
Remember those GM combo carbs, "throttle body injection" I think they were called? Or Jeep also had a electronic carb that was a nightmare.
The best carbs are pre-emission types. British SU carbs are also brilliant if you understand them, and not at all troublesome.
Old German Solexes and Zeniths however can be diabolical when used in tandem.
#4 of 399 Makes me feel old...
May 06, 2005 (5:50 am)
When I realize the average mechanic/technician today hardly knows what a carburator even is!
Quadrajets came out in 1966 and I can remember how they were bad mouthed by a lot of "mechanics" who didn't understand them. Like div says, they were really well designed. The worst were Ford's Varible Venturi carbs and Chrysler's Thermo Quads.
I used to enjoy watching a good "carburator guy" tear one apart and restore it to new.
These guys are a disappearing breed.
May 06, 2005 (7:47 am)
What's even worse is many times people without experience will attempt to modify their carburetor systems without much forethought. You just can't bolt on a bigger carb without doing other things as well, like a good intake system.
We were just working on a Porsche 914 that someone had stuffed a 3.0 liter carbed engine in. Ran like crap---had larger venturi carbs on it but nothing else added. So we switched to stock venturis, tuned the car and it ran about twice as well. So much money spent and wasted!!
May 06, 2005 (4:17 pm)
There used to be a BLIND tune up guy at a Chevy dealer in So. Calif. A lot attendant would pull the cars in and out for him. He could overhaul a Quadrajet in record time.
I refused to believe it until I saw him at work one day!
May 07, 2005 (10:17 am)
A lot of carb adjustments are done with a feeler gauge, so you don't need your eyes for that. Still, quite an achievement!
May 07, 2005 (12:11 pm)
Think of the balls and springs etc he had to deal with and be sure not to lose.
He had to ask somone to read the scope pattern for him if he couldn't figure out a miss or something. He was incredible!
Remember Sun scopes? Talk about a thing of the past!
#9 of 399 Good Carburator Guys
May 11, 2005 (6:08 pm)
I'm getting the carb on my 67 Galaxie worked on this summer. Let me tell you, finding a good carburator guy who is not charging an arm and a leg because most of his customers are wealthy musle-car owners is not so easy anymore.
I use my mechanic mainly because his father is semi-retired, but does come in to do any of the carburator work they get. I've never seen top shelf older cars, but I've seen them working on 6 cylinder Mustangs, MGB's, Buicks, etc.
#10 of 399 Still a few out there...
May 12, 2005 (5:59 am)
Trouble is, today's mechanics/technicians don't like to rebuild things. They just replace components in many cases.
An old school guy would NEVER put an assembly line "rebuilt" carburetor, starter, alternator or anything else on a car. They wouldn't stake their reputation on the unknown quaity of a so called "rebuilt" part.
Instead, they would carefully disassemble the part and with a great deal of pride, overhaul it to as new condition.
I guess today's labor rates forbid this now?