Getting carb work done...
02-13-03, 12:32 AM
#1
Senior Member
Thread Starter
Getting carb work done...
Well, my newly rebuilt 12a (new housings) is running kinda crappy, and I know that it is the carb. The carb has never been rebuilt. The floats are all screwy, horrible idle, and the accel pump went out on me so it leaks gas badly when messing with the throttle.
SO. Should I take my car to a mechanic to get them to rebuild my carb (note: I don't live in a big city, and there are no rotary people around this area... so it'll be some goofy piston mechanic...) -OR- should I go for a new carb and intake manifold? I want reliability and conisistancy.
What shall I do?
I guess shipping it off for work to be done too is an option.
Input appreciated.
SuperPhly
(Lubbock Texas)
SO. Should I take my car to a mechanic to get them to rebuild my carb (note: I don't live in a big city, and there are no rotary people around this area... so it'll be some goofy piston mechanic...) -OR- should I go for a new carb and intake manifold? I want reliability and conisistancy.
What shall I do?
I guess shipping it off for work to be done too is an option.
Input appreciated.
SuperPhly
(Lubbock Texas)
02-13-03, 04:11 AM
#2
Senior Member
Join Date: Mar 2001
Location: -
Posts: 520
Likes: 0
Received 0 Likes
on
0 Posts
Well, a good carburetor man is worth his weight in gold.
A lot of mechanics will claim to know how to rebuild a carb, but after they do the "rebuild" and the "carb adjustments" it runs like crap. The best carburetor guys are known through word-of-mouth in the racing scene, so I'd suggest asking the racers or the racing shops, and if you get more than one reference to a guy then you can take the car to him and see if he'll do the rebuild and adjustments on your carb. Good carb guys aren't cheap, so ask for an estimate - then you'll have a better idea of what to do.. rebuild or new.
A lot of mechanics will claim to know how to rebuild a carb, but after they do the "rebuild" and the "carb adjustments" it runs like crap. The best carburetor guys are known through word-of-mouth in the racing scene, so I'd suggest asking the racers or the racing shops, and if you get more than one reference to a guy then you can take the car to him and see if he'll do the rebuild and adjustments on your carb. Good carb guys aren't cheap, so ask for an estimate - then you'll have a better idea of what to do.. rebuild or new.
02-13-03, 07:11 AM
#3
Airflow is my life
Rebuilding a stock carb is cake. A kit is less than $30. Are you decent with tools? Its just a tedious job. After the first dozen or so its easy. Take your time, remember a CLEAN environment is critical. DO NOT use metal wire to clean jets, toothpicks work good.
02-13-03, 08:40 AM
#5
Nikki-Modder Rex-Rodder
Join Date: Feb 2001
Location: Trying to convince some clown not to put a Holley 600 on his 12a.
Posts: 2,890
Likes: 0
Received 14 Likes
on
6 Posts
The Banana know as much or more than I do!
I've built many carbs, but all for non-emissions cars - IE, the crap bolted onto the carb was always pitched in the "parts pile".
I recently rebuilt Supraslincs carb, and it was a challenge in that it had been two years since I had to replace all the emissions crap.
I took digital pictures for reference as I stripped the crap off the carb. A monkey, if given long enough, could figure out where all the parts go. But exactly which screws go where (they are different lengths) as well as the complexity of the linkages can be tricky without at least taking notes.
Like I said. a digicam to snapshot pics during stages of disassembly is worth a gazillion words of tedious explaination.
Lay out news print- Meat wrapping or white paper is best cause you can see parts easier.
Have a coffee can or better, a shorter container for keeping parts.
Don't worry about cleaning the emissions parts too much, but at the same time, don't let them get greasey on the gaskets.
I brass brush the whole thing befor taking anything off first.
Always keep in mind that the carb housing and airhorn are made of very crappy quality cast aluminum. It's very soft and has poor granular structure, so it's prone to cracking.
Excercise extreme caution if using a razor to clean off gasket material, as it's easy to nick the metal. Be very careful not to strip threads.
One brass wieght and steel check ball set- located under the brass plug over the accelerator pump. Another set (different size wieght) is located underneath the accelerator pump nozzel, between the small (primary) venturis (bores).
A third wieght is located under a large faced screw on the very edge of the secondary side of the carb; on top. No need to open that, but if you do, just be aware of the brass wieght.
These five things are the tiniest, easily loose-able pieces cause they roll.
A good kit will have the wieghts and check *****, but not always.
If the ***** are not rusty and can be cleaned up (wieghts as well), then you can re use them.
You'll get needles and seats in the kit.
The seats are incredibaly hard to get out sometimes. It's a brass thick walled tube screwed into the bottom of the float bowl cover. They have four holes in the sides. I use a perfectly fitting rod to loosen these and tighten in the new ones. The smooth end of an appropriate sixed drill bit will work great.
Pliers will score the outside of the brass seat, and probably not damage anything, but you don't need to worry about little flakes of brass getting lost in the workings of your carb! (Plus if you slip, you can damage the cast aluminum hinge directly behing the seat).
Just do it! Get it all cleaned up, and the re-read this and do some searching. All will become very apparent once surgery begins.
We'll all walk you through anything you have questions about.
While you're doing research here, you might want to concider some very simple carb mods you can do, such as wiring your secondaries for mechanical operation, increasing secondary jet size, or even increasing accelerator pump capacity and opening up the nozzel jets. All these things are easy to do, difficult to screw up, and much easier to do with the carb off the car. None will screw up the carbs ability to idle, so don't worry about complicating the initial tuning once your done because you've introduced new variables- the mods will serve you in the throttleing of the carb only.
Have fun!
I've built many carbs, but all for non-emissions cars - IE, the crap bolted onto the carb was always pitched in the "parts pile".
I recently rebuilt Supraslincs carb, and it was a challenge in that it had been two years since I had to replace all the emissions crap.
I took digital pictures for reference as I stripped the crap off the carb. A monkey, if given long enough, could figure out where all the parts go. But exactly which screws go where (they are different lengths) as well as the complexity of the linkages can be tricky without at least taking notes.
Like I said. a digicam to snapshot pics during stages of disassembly is worth a gazillion words of tedious explaination.
Lay out news print- Meat wrapping or white paper is best cause you can see parts easier.
Have a coffee can or better, a shorter container for keeping parts.
Don't worry about cleaning the emissions parts too much, but at the same time, don't let them get greasey on the gaskets.
I brass brush the whole thing befor taking anything off first.
Always keep in mind that the carb housing and airhorn are made of very crappy quality cast aluminum. It's very soft and has poor granular structure, so it's prone to cracking.
Excercise extreme caution if using a razor to clean off gasket material, as it's easy to nick the metal. Be very careful not to strip threads.
One brass wieght and steel check ball set- located under the brass plug over the accelerator pump. Another set (different size wieght) is located underneath the accelerator pump nozzel, between the small (primary) venturis (bores).
A third wieght is located under a large faced screw on the very edge of the secondary side of the carb; on top. No need to open that, but if you do, just be aware of the brass wieght.
These five things are the tiniest, easily loose-able pieces cause they roll.
A good kit will have the wieghts and check *****, but not always.
If the ***** are not rusty and can be cleaned up (wieghts as well), then you can re use them.
You'll get needles and seats in the kit.
The seats are incredibaly hard to get out sometimes. It's a brass thick walled tube screwed into the bottom of the float bowl cover. They have four holes in the sides. I use a perfectly fitting rod to loosen these and tighten in the new ones. The smooth end of an appropriate sixed drill bit will work great.
Pliers will score the outside of the brass seat, and probably not damage anything, but you don't need to worry about little flakes of brass getting lost in the workings of your carb! (Plus if you slip, you can damage the cast aluminum hinge directly behing the seat).
Just do it! Get it all cleaned up, and the re-read this and do some searching. All will become very apparent once surgery begins.
We'll all walk you through anything you have questions about.
While you're doing research here, you might want to concider some very simple carb mods you can do, such as wiring your secondaries for mechanical operation, increasing secondary jet size, or even increasing accelerator pump capacity and opening up the nozzel jets. All these things are easy to do, difficult to screw up, and much easier to do with the carb off the car. None will screw up the carbs ability to idle, so don't worry about complicating the initial tuning once your done because you've introduced new variables- the mods will serve you in the throttleing of the carb only.
Have fun!
02-13-03, 08:55 AM
#6
I read your email
Originally posted by Sterling
... increasing secondary jet size
... increasing secondary jet size
Trending Topics
02-13-03, 09:42 AM
#8
I read your email
Drilling can be tricky I'd buy new larger ones...... so 160 is the stock secondary jet size eh? Yeah, I know it's a trial-n-error thing so I'd probably get a few sizes up from 160 they aren't that expensive.
How difficult is it to change the secondary jets while the carb is on the car? If it's doable, how do ya do it?
How difficult is it to change the secondary jets while the carb is on the car? If it's doable, how do ya do it?
02-13-03, 10:02 AM
#9
Airflow is my life
Get a couple smaller too.
Doable. If your doing "testing", try leaving the screws out, just holding the top on with the stud in the middle. Then you can look down into the bowls to change jets. Use a proper size tool, you dont want to nick the slot, itll change the flow rate slightly.
Doable. If your doing "testing", try leaving the screws out, just holding the top on with the stud in the middle. Then you can look down into the bowls to change jets. Use a proper size tool, you dont want to nick the slot, itll change the flow rate slightly.
02-13-03, 12:59 PM
#10
Nikki-Modder Rex-Rodder
Join Date: Feb 2001
Location: Trying to convince some clown not to put a Holley 600 on his 12a.
Posts: 2,890
Likes: 0
Received 14 Likes
on
6 Posts
Sometimes I forget (And I feel comfortable speaking for Carl, too-) that some of you all still have all of your emissions control **** in place.
When asking guys here about carb modding advice (or giving it), it's very important that you say whether that **** is in place or not.
A naked carb is MUCH easier to mess around with. In fact, it's practically impossible to swap out jets on a carb without stripping half the emissions crap off just to get to them.
When I talk about swapping jets, ect, I may write as if I simply "pop in jets" whenever I feel like it. -Well, I do!
But that's because I have a severly modified, VERY naked carb!
If you are rebuilding and emissions is a critical concern, you may be better off not modding the carb in any way what so ever. I simply do not know what will effect emissions testing. There are several types of testing with different criterium, and I can only make educated guesses as to what mods will effect what; and all in theory at that.
Emissions are a PITA. Good thing we're all socked with the ****, and not our nearest coal burning production plant.
This is why everyone subjected to this bueracratic bullshit should have two carbs - one to please Whitman, and one to please you!
When asking guys here about carb modding advice (or giving it), it's very important that you say whether that **** is in place or not.
A naked carb is MUCH easier to mess around with. In fact, it's practically impossible to swap out jets on a carb without stripping half the emissions crap off just to get to them.
When I talk about swapping jets, ect, I may write as if I simply "pop in jets" whenever I feel like it. -Well, I do!
But that's because I have a severly modified, VERY naked carb!
If you are rebuilding and emissions is a critical concern, you may be better off not modding the carb in any way what so ever. I simply do not know what will effect emissions testing. There are several types of testing with different criterium, and I can only make educated guesses as to what mods will effect what; and all in theory at that.
Emissions are a PITA. Good thing we're all socked with the ****, and not our nearest coal burning production plant.
This is why everyone subjected to this bueracratic bullshit should have two carbs - one to please Whitman, and one to please you!
02-13-03, 03:19 PM
#12
Junior Member
Join Date: Dec 2002
Location: PA
Posts: 11
Likes: 0
Received 0 Likes
on
0 Posts
Call around. I couldn't get anyone local to touch my import carb (actually, the response was usually much more harsh). If you do convince someone to do it... well then it's hit or miss. I vote to send it out.
Before you do anything, check your local emissions laws. If you look hard enough, you can usually find ways around these things. You'll be much happier w/o all that **** cluttering up your engine bay. I'll agree with carl and sterling. W/o emissions, jet/float changes are a snap. With them, well, have fun!
Before you do anything, check your local emissions laws. If you look hard enough, you can usually find ways around these things. You'll be much happier w/o all that **** cluttering up your engine bay. I'll agree with carl and sterling. W/o emissions, jet/float changes are a snap. With them, well, have fun!
02-14-03, 07:37 AM
#14
Airflow is my life
I agree totally Sterling. 82, just have 2 setups. 
If not, its actually easier to do it Felixs way. Which is to disassemble the carb on the car. See my sig for his website.
If not, its actually easier to do it Felixs way. Which is to disassemble the carb on the car. See my sig for his website.
Thread
Thread Starter
Forum
Replies
Last Post
thecody59
1st Generation Specific (1979-1985)
40
08-23-15 06:41 PM