News:

Due to a technical issue, some recently uploaded pictures have been lost. We are investigating why this happened but the issue has been resolved so that future uploads should be safe.  You can also Modify your post (MORE...) and re-upload the pictures in your post.

Main Menu

First Time Rochester Rebuild

Started by 71 Fleetwood, August 13, 2021, 06:15:53 PM

Previous topic - Next topic

0 Members and 1 Guest are viewing this topic.

71 Fleetwood

I did consider giving it a go and doing it myself.   I was cautioned by the guy in MO, whom I thought was a reputable and knowledgeable, that particular carb was not one for a first time rebuilder.

  I'm about to the point where I want to order a rebuild kit for my Rochester.  I have no experience with this carburetor.  Am I crazy  :o to try it?


1971 Fleetwood Sixty Special Brougham

fishnjim

Only if you've never done one or don't know how to rebuild carbs and don't want to learn.
You'll need somethings.  Place suitable to do it.   A container big enough to soak in "carb cleaner" and enough carb cleaner to cover, circa 2 gallons.  There's usually a small parts container in the carb cleaner can.  small scrub brushes.   A 2-3 gallon rectangular PE tub from swimming pool chemicals work good w/lid.   "Parts cleaner" also works.
Compressed air.   Small tools.  rubber gloves, shop rags, paper towels, steel wool, etc.  Sink and running water to wash off cleaner.   Bead blaster cabinet is nice for appearance, but not necessary.
A clean covered work bench big enough to take it apart and line out all the parts for re-assembly.   I use a flat tub, water heater drip pan when fluids, piece of carpet foam, for parts retention, etc. so nothing spills or roll off the bench.   Newspaper is messy and parts can roll under the sheets.   I have roll paper I use.   One set-up for dissassembly and another for clean and reassembly.
Good set of instructions.   I have the rochester one copied below.   May not be exact, but search for your number carb.

TJ Hopland

If you have done various other carbs even small engine ones these are not that crazy.   If you have never done any sort of carb and don't really know any of the bits or how they work then one of these may be a little much. 

Working in some sort of tray is an excellent idea,  keeps small parts from rolling away.   I use one of the purple de greasers to do most of the cleaning of the big main body parts.  A can of carb spray for the rest.   Wear safety glasses when you squirt the cleaner or air in various passages,  you never know where they may exit,  could be right in your face. 

What is wrong with your existing one?    If its really screwed up or there are any signs that its been abused you would be better off taking to an expert that can spot the issues or abuse.   Since you won't know what you are looking at you will likely end up putting it back the same wrong way the last person did.     If yours is just dirty and weepy then give it a go.   
StPaul/Mpls, MN USA

73 Eldo convert w/FiTech EFI
80 Eldo Diesel
90 CDV
And other assorted stuff I keep buying for some reason

wheikkila

I have not checked but have you looked on you tube on how to rebuild this carb. It would be the first place to start. I would start looking for somewhere to send it to just incase you chose to send it out. If you decide to do it yourself. Find a manual for the carb you have. You will need it.
Thanks Wayne   

TD Alex

Thanks y' all going to go for it!!
1967 Sedan DeVille
2007 Jaguar XK Conv
1998 Land Rover Range Rover
1992 Alfa Romeo 164LS
1989 Alfa Romeo Spider
1985 Cadillac Eldorado
1972 Chevorlet Caprice Classic Convertable
1972 Buick Electra Custom Limited
1970 1/2 Volkswagon Karmen Ghia Convertable
1967 Ford LTD
1967 Volkswagon Micro Bus step thru
1965 Volkswago Fastback

V63

#5
some suggestions for a first time ...assuming your carburetor was reasonably in service, with maybe an accelerator pump issue?

Best mindset on this project should be effectively just clean and replace the supplied parts.

I would use a spray carburetor cleaner vs a soaking

I would avoid removing idle mixture screws. There are overwhelming 'adjustments' and measurements that 'less is more' and I typically ignore unless a specific issue needs attention.

The trickiest part is There is a 'Sputnik' looking assembly with 2 dangling needles that upper part protrudes thru the gasket. They must 'seat' with a bit of a spring tension. It's a challenge holding them seated AND lowering the top cover. A thin strap of metal is helpful. maybe a thin wood coffee stir stick.

I use ATF Or marvel to assemble and lubricate the parts,  moreover I put a splash  in the bowls  for initial start up to mix with the fuel. I prime the carb with a few ounces of fuel thru the vent stacks for initial start up.

The last kit I received had zero instructions, I guess a 5 cent xerox copy just overwhelming the costs🤦🏻‍♂️🙄

TJ Hopland

You really should remove the idle mixture screws to aid in the cleaning of their passages.   Trick is before you remove them you count the number of turns it takes to seat them so you can put them back to that point as your starting point.   Usually you would count in half turns.
StPaul/Mpls, MN USA

73 Eldo convert w/FiTech EFI
80 Eldo Diesel
90 CDV
And other assorted stuff I keep buying for some reason

The Tassie Devil(le)

The other secret to rebuilding any carby, is to remember NOT to lose any ball bearingsa that are in the passageways.   The Rochester has them, and I have had no trouble rebuilding them when I have had to.

But, never had any bad enough to require re-bushing the throttle shafts.

Bruce. >:D
'72 Eldorado Convertible (LHD)
'70 Ranchero Squire (RHD)
'74 Chris Craft Gull Wing (SH)
'02 VX Series II Holden Commodore SS Sedan
(Past President Modified Chapter)

Past Cars of significance - to me
1935 Ford 3 Window Coupe
1936 Ford 5 Window Coupe
1937 Chevrolet Sports Coupe
1955 Chevrolet Convertible
1959 Ford Fairlane Ranch Wagon
1960 Cadillac CDV
1972 Cadillac Eldorado Coupe

"Cadillac Kid" Greg Surfas 15364

Richard,
My suggestion would be to buy a "core" carburetor and practice taking it apart and putting it back together before you work on yours.
Greg Surfas
Cadillac Kid-Greg Surfas
Director Modified Chapter CLC
CLC #15364
66 Coupe deVille (now gone to the UK)
72 Eldo Cpe  (now cruising the sands in Quatar)
73 Coupe deVille
75 Coupe deElegance
76 Coupe deVille
79 Coupe de ville with "Paris" (pick up) option and 472 motor
514 inch motor now in '73-

Roman Z

I had issues with my Rochester as well. I took it apart 4 times same idling issues. I sent it to an outfit in Georgia they had it back to me in about two weeks. No issues after that.
https://www.carbs.us/
A little pricey but was worth it to me.

TJ Hopland

Ya if it was just dirty with dried out gaskets and such and its never been abused most of us can get one clean and back together without too much trouble.   Problem comes in if there is a real problem or the last person did something dumb or wrong.   Most of just just don't know what we are looking at.   We don't know where every passage is or isn't supposed to connect.   We can't tell just by looking if the holes are the right sizes.  We can even miss simple things like does it have the right gasket?
StPaul/Mpls, MN USA

73 Eldo convert w/FiTech EFI
80 Eldo Diesel
90 CDV
And other assorted stuff I keep buying for some reason

wheikkila

You just hit the nail on the head. That is the big question. If it is a virgin carburetor then you don't have a problem with gaskets or is it assembled properly. But if it has been worked on by who know how. But, when you send it to someone that only rebuilds these carbs. They know them well and they work like new when they are done.
Thanks Wayne   

fishnjim

If you're going to rebuild the carb, rebuild it, don't play around with internet jive.  If nto, buy a new aftermarket one.   
The idle screws come out to clean the passages.   The seats have to be checked for damage from wear and overtightening.   Wiping off the outside, won't do the job.   Not rocket science.   Look at the exploded diagrams and follow the procedure.   The linkages can sometimes go on backward, so take pictures before disassembly.   There's online sources too.   I never lubricate the inside of the carb.   

Cadman-iac

#13
  Another thing that you should be aware of is how easy it is to bend the primary rods if you don't get them lined up with the jets as you are installing the power piston.
This step is done after the plastic filler piece goes in place. It blocks your view of the jets somewhat, but not completely.
I'm not positive that the earliest quadrajets have to have this piece installed first, but later ones do. So if it does have to be installed first, and you will be able to tell by the size and shape of the hole in the center, then you can use a small flashlight to see down into the bowl and view the jets as you're lowering the rods into place. Once they're in the jets, make sure you don't let the piston come back up before you get the retainer in place. If memory serves, the early design retainer was a metal ring that wrapped around the tower the piston goes into, and it has a couple of small tabs that extend inward over the piston to keep it from coming out.
The later design has a small plastic ring that drops down into a groove at the top of the piston tower, and it's a slight press fit, or should be if it's not worn out.
And before you install the piston and rods, make sure that you put the spring back in place below the piston, or you will be doing this all over again. That spring is what raises the piston and rods up as the engine requires more fuel. The high vacuum at idle keeps the piston down, but as vacuum drops off, the piston rises to meet the needs of the engine.
But my main point is just be careful not to damage those rods. They are sometimes hard to find, and there are a bunch of different ones. If you have to find another one or pair, there's a number and letter code stamped into the side of the rod.
Those can range from something like 37 up to 50 something. I'd have to look it up to give you the complete range.
Also, when you get to the jets, make sure that you have a screwdriver with a wide enough tip in good condition, or they can be damaged trying to remove them.

As was mentioned in an earlier post, you may want to find another quadrajet to practice on before you attempt to repair yours. Especially if you have the original carburetor that is supposed to be on your car, and you intend to keep the car original.

Rick
CLC# 32373
1956 Coupe Deville A/C car "Norma Jean"

TomJudd

 General tip......lots of pictures!! You will never remember what u think u will. Specifics notes as to the order of disassembly. MORE PICS.....Clear a large bench and sweep floor well first. Good odds u will drop small parts.. GOOD LUCK

fishnjim

This could have been rebuilt by now!!!!