I have a '72 Olds 98 with a 455 and Rochester Quadrajet that I'd like to get a rebuild kit for. I assume, like most all other carbs, I need to find the precise kit for my carb. I can see, vertically, to the right of where it says "Rochester Quadraject" on the drivers' side, the numbers: 70412251 RE and then a 1312 below.

Can anyone tell me how to look up this exact carb for a rebuild kit?

Thank you!!!!

 

check Mike out I have used them several times. https://www.carburetor-parts.com/ They can help you.

 

Give the parts store the number you found and get the kit, new float and fuel filter.

Any more carb kits cover multiple applications, but the parts in the kit are generic to all of them. Kit will include new gaskets, pump, needle and seat, check ***** and linkage clips. Float is sold separately.

Do a good teardown, cleaning and inspection, then reassemble using the 1972 factory Chassis Service Manual. You may have to tweak the new float arm to set float level correctly.

 

70412251 is the carb number. I still use Hygrade kits for most of my rebuilds. I also suggest replacing the plastic float as a preventative measure.

 

Compare the old gaskets to the new, they must have the same holes. Lay one on top of the other and compare both sides old-to-new, once the correct gaskets are identified remove the other gaskets supplied in the kit from the work/assembly area. I learned this the hard way.

Good luck!!!

 

I worked at auto parts stores through the 80s and 90s, and as rocketraider said the kits are universal and cover multiple applications.

The Hygrade kit Joe mentioned is very good and is what I have used over the years. NAPA has been my go-to for carb kits for decades.

I use spray can carb cleaner to blast through the passages to ensure there’s no blockages.

 

I'm a true dinosaur. I still have a 5 gallon bucket of carb and parts cleaner, and several metal parts baskets. The good stinky stuff that has gotten hard to find and that you have to remember to not put plastic parts in!

Then a triple water rinse and about 50psi of compressed air to blow out all the passages. Wearing safety glasses of course.

 

I don't think you could go wrong with the rebuild kits from Cliff Ruggles (he wrote a pretty good book on the QJet as well):

https://cliffshighperformance.com/pr...t-rebuild-kits

The accelerator pump seems to be the weak spot in the cheaper kits and I know the ones Cliff sells are really good quality.

 

SInce the owner of Quadrajetparts.com passed away about a year ago I have bought three kits from these guys:

https://quadrajetpower.com/

Very complete kits and they have the updated accelerator pumps that will survive the Ethanol in the fuel. I have been very happy with them. You can look up your carb number on their site.

I would stay away from parts store kits. Most of them have been sitting on the shelf for years and the gaskets are dried up and they will not have the newer pump material.

 

Thank you, and others, for options on which kits to buy. My biggest question was knowing how to get the RIGHT kit that fits or matches mine. I trust there are many different Rochester designs, sizes etc so I’m not sure how to find a kit that Matches mine.

 

As previously stated (Post #3 - rocketraider) kits will include various parts/pieces. Use the ones specific to your carburetor. Even when you purchase a kit specific to a select carb. # there will be some parts in the kit which fit select variants of that specific carb. It's pretty easy really - match the parts you need.

 

Ahhhhh. Now I get it. Thank you

 

I've found having a flat surface to work on makes for an easier rebuild, etc. when working on a carburetor.. Grab a piece of 2"x4", cut & secure into four pieces, drill a couple holes for the mounting bolts of the carburetor, fasten down the bolts and you have a great mounting stand to work on. The interior base of the carburetor nestles into the center of the 2"x4" void. Nice platform to work from quick/easy to build.

 

I guess this depends on if you are a woodworker or a metal worker. I've found it easier to just use hardware store bolts and nuts. I have to be honest, I rarely have the carb apart long enough to even take the time to put these in.

 

I think we agree a stable platform lends itself to a more suitable work environment.

 

Using the resources noted in posts 3, 4, 6, 8, and others - CONTACT the seller and tell them which carb you have (post #4) and any of the reputable sources listed will get you what you need.

 

Don't get hung up on that. A Ninety Eight 455's kit is no different from a Cutlass 350's.

Give the parts store the 704xxxx number you've found at the left rear corner of the float bowl. It's that simple. The kits include parts for multiple applications as a matter of consolidation and economics. The big thing is the kits include multiple air horn, venturi cluster and throttle plate gaskets. Rebuilder is expected to match the correct new gasket to the carburetor and toss the unused ones.

Here's the 1974 FACTORY parts book info on this repair kit, which Oldsmobile calls an "OFF-KAR" kit.

Group 3.725 p/n 7039258, 71-74 4BC.

This means the FACTORY sourced Rochester kit includes parts for ALL 1971-1974 QuadraJet four-barrel carbs, on both 350 and 455 engines.

That p/n is long obsolete and if you find one it will be decades old. In that time the gaskets and pump diaphram will have dried out/curled up and won't be worth the effort to install. Been there.

If you're still unsure about the advice we've given you, send the carburetor to Sparky's Carbs, QuadraJet Power or other reputable carb specialist. They'll tear it down, assess condition, clean it, reassemble it using ethanol-resistant components and set everything to factory specifications.

 

So, I am happy to report that I've been working with the guy at Quadrajetpower and bought a complete rebuild kit. He's actually been great getting back to me on questions. But I'm stuck on 2 things (at the moment) and hoping you good folks may know:

The kit included a Power Piston Retainer, a little white plastic bushing (see first pic attached) - I know where it goes on the Power Piston but no idea how to get it there. Can't slide it up from the bottom, nor down over top ...unless I'm supposed to pull out (somehow) the "T" at the top that supports the rods.
The kit also included 2 Choke Shaft Seals, the little black rubber seals (see second pic). . I put one of them inside the larger black plastic "disc" that the choke shaft arm goes through an into the carb itself. But I don't know where the other one goes

If anyone can shed light on these for me, I'd be grateful. Thanks all!!!!

Jay​​​​​​​

 

The ring is spilt so it can be opened and put onto the shaft:

https://quadrajetpower.com/power-piston-retainer-new/

 

Thank you. That's what I thought - but didn't want to slice it only to find out I shouldn't have. :-)

 

All set on these, folks. Thank you. The guy at Quadra Jet Power has been incredibly helpful (emailing me multiple times). Can recommend him/them enough!!!

Jay

 

Thanks for the info and recommendation. It’s helpful to get first-hand information about dealing with a company on the internet. Otherwise it’s just another web page. Good to know these folks are knowledgeable and response. 👍

 

I'll second Cliff's kits. I understand he's out of the rebuilding business himself but the kits he supplies are the best