The Stovebolt Site Forums The Shop Area Engine Shop Rochesters....leak from throttle linkage?

As a newbie, here is another post. After lots of reading (this site is great) it seems that these one barrels will start to wear out around the shaft that runs through them.

My current carb is spitting a bit of gas out that linkage right onto the intake.

I read that there is supposedly a bearing that should be fixed, but rarely is, in the rebuilds.

How do I go about fixing this?

Thanks
Sablesurfer

The throttle body can be opened up and have shaft bushings installed but that's pretty involved. Find a rebuilt one at an auto parts store. In my area the core charge is $50.00 so you'll need yours for a trade in anyway.

Curt B.

That happens when you shut off the motor & the trapped fuel pressure in the pump to carb. line rises due to heat & overpowers the float valve in the carb., spills over, drops onto the butterfly, runs across its shaft & out where you describe. Has to be some clearance there for it to operate. If the shaft/base wear too much you will know it by it not being able to idle down to a normal RPM due to the air (vacuum) leaking in. Try lowering your float level a bit, that helps usually. When its really wore out as stated before you need a rebuilt one. Good luck finding one in the store thats been rebushed. May be more easy to find another old one in better shape, all you need is the base part. Some of these have sat for many years & never got worn much. I've gambled on some ebay ones for a cheap price & got lucky before. Doug

Don't waste your time with 1bbl Rochesters...switch to Carters and enjoy driving again. Just read the loads of posts on this issue using the "search" feature of this site.

Gas can,t run out of there unless it is flooding for some reason. It could be perculation like Dessert dog says or a bad needle & seat or incorrect float level.

Well, I would dig into it to check/reset the float, but neither O'Reily or AutoZone can find a rebuild kit.

No one seems to be sure where to look on the carb for the correct number.

If I get a rebuilt one...is there anything in particular I need to look for...company wise?

Still looking into the Carter YF thing.

NAPA here would get a reman based on year and application - the generic ol rochester kit will have all you need, they cover the whole range of models for the small parts/gaskets

Bill

Instead of getting a remanufactured rochester, I suggest considering switching to the 2 barrel Holley-Webber sold by Langdon's Stovebolt. The money would be almost the same but the performance would be better, and the gas consumption would be less.

Now then with all said,I read somewhere here on one of these here posts where it was recomended to set the the float 1/16" of an inch less then the manufactures specs.Ok,then what would be the setting for the 1 barrel rochester float setting? Thank you.

I agree with NM51....I fought with a worn out Rochester, bought an Azone rebuilt...it was in worse shape than my old one. The Holley/Weber is absolutely great...right out of the box!!! More power, smoother idle, better mileage and no more gas fumes.

However, I had a friend who removed the Rochester throttle shaft, drilled a shallow hole on each side of the base....found an "O" ring that fit snuggly on the throttle shaft and then used epoxy glue to hold a little cover plate that kept the rings from popping out. Used double gaskets on the top horn, reset his float level.....it still ran like crap but at least it didn't leak out the side.....just into the intake.

Be happy...go with the Holley/Weber!!!!

The Rochester is not a bad design, only a victim of poor procedures. I have run them for many years, never had one to leak or run rich. I bother to tune them properly, with the right jetting. On a 1954 with 235 engine I have regularly achieved 24 m.p.g. and held the record at several drag strips for stock class with the same vehicle. My 1953 with 235 Rochester carb. and Fenton headers ran a 16.15 e.t. at 79.65 m.p.h. I don't know of a stock 235 that ever went any faster, and have several trophies to prove it. I am running two Rochester carbs on my 1954 GMC 248 pickup and mileage is good and it runs great. It's not necessary to change carbs to make your 235 run good, just a little patience.

Chevman, it's good to hear you say that. The Rochesters are trashed a LOT in this club. My builder agrees with you. He swears he can make dual Rochesters work as well as any other carb that will fit my intake. It just takes know how from a skilled old timer who has done a few. The problem is that most guys who know how to tune them properly are retiring or getting buried.
And... as I've mentioned before, I'm currently running a single Rochester on a mostly stock 235 w/hei and fentons. It runs great, doesn't leak, and I can get over 20mpg if I keep my foot light on the pedal. When my 261 is finished, I'll be running 2 NOS Rochesters on an Edelbrock intake.

Hey Sablesurfer. Try Carquest for that kit. They should be able to supply it by application. Also Classic Parts & L.M.C. are in our area & have good over the counter service. You can probably o-haul it yourself or bring it by my shop & i,ll do it for you. E-mail georgec2434@yahoo.com

That leaking out thing just happened to me today. Ok so where do I find instructions to stop the leaking or adjust the float? Mine is a newly rebuilt carb that was running fine until about an hour ago.

Like others in the forum, I've got a Carter YF and it is a much better carb. Is it original for mine? Not even close, but that is one sacrifice to stock I'll take so it runs well.

I'm not even sure what type is even on the truck.

i bought a bebuild kit at oreilly for about $5 a couple of years ago. i bet if you talked to the right person they have it.

I futzed with the Rot-Pot B for years on my Bel-Air. If they're not leaking, the car is out of gas. Forget keeping one dry on the outside. Its an exercise in frustration. I switched to a Holley 4bbl on a Clifford manifold about 5 years ago. Its great.

Orielly caries the kit for your carb just tell the clerk to forget the computer and look in the books. They have a lot of the parts for the older cars and trucks if you can get them to spend a little time to look for them. If you have a Bumper to Bumper in KC they have access to a great deal of hard to get parts for older trucks.

Thanks. After searching and reading many posts on the Stovebolt, I'm going to pull the top off the carb to see if the float is stuck.

You may have mentioned it already and I just missed it, but just in case ... you do have the insulator installed between the carburetor and the manifold, right? That slows the heat transfer and reduces the likelihood of percolation.

Yes.

In all seriousness, here's what slowed down the leaks for me:

Install a good carb kit. Set float level slightly lower than what is called for. This can help to keep fuel level from sitting right at the airhorn gasket. Bush the throttle shafts, this helps reduce fuel and vacuum leaks around the shaft. Don't overtighten the air horn, stagger tighten the screws like you would a head gasket. Use carb insulator to reduce fuel percolation. Use a good fuel filter to keep trash from sticking the main needle & seat.

Today, I found the float to be incorrectly set which allowed gasoline to run out of the firetruck. I set it at 1.75" and tried to start it again. It started but didn't leak like before. I did get some seapage around the horngasket when the truck was shut off. I'll set it a little lower on Monday and try it again. Thanks for the advice in addressing this issue.

Greetings all.

Just a quick note on the Rochester, in the vintage Land Rover world the Rochester is an UPGRADE from the Zenith or Solex. I have a 1966 2.25 iron lump pushing along some very square aluminum. Now I'm starting to wonder what else is out there for us.....

Now for the stovebolt content. I just aquired the family 1937 PU, and it's time to get that up and running once again.

Well, since we're still talking Rochester I'll put my .02 worth in. I don't understand the knock on the "rot-pots". I've used them for years. My 235 starts right up (unless it's been sitting for a week), idles good, accelerates good, no hesitation, no leaks, no problems. I rebuild them with quality parts, use care in assembling and adjusting. I guess I could go out and spend some more $$ for a "better" carb but what for?

I don't know 'nuttin' about leaking Rochesters, but I will say this...if you are lucky enough to live anywhere near Lenexa, Kansas you have your own Mr. Goodwrench-bender Ret. There isn't a week that goes by on this forum that he doesn't volunteer his shop and his experience to help one of his Stovebolt neighbors. He must still love to 'wrench'!

Stuart

causes,,,high float setting,,,needle leaking by,,,,also check heatriser valve be sure it is working is stuck closed it will cause over heating of carb causing gas perc and flodding after shut down....doc

Thanks for the info. Since I adjusted the float, it has stopped leaking.

Probably a couple of different issues running in this thread:

Assuming proper float adjustment, fuel leaking from around the throttle shaft is normally caused by fuel expansion once the engine has been shut off. The underhood heat expands the fuel in the fuel lines, creating pressure that the float cannot stop, and dumps fuel into the carb. This raise the fuel level above the main discharge nozzles, and the fuel runs out the discharge nozzle down on to the throttle plate which is closed. It then runs out of the throttle body by the throttle shaft and onto the manifold. THIS ISSUE IS NOT LIMITED TO ROCHESTER CARBS. The issue may be be minimized by installing a "return line" to the tank.

Now as to the Rochesters: Crazyfish, I would certainly agree that the Rochester is an upgrade to the Solex carbs and I would also agree with Chevman32 that they CAN be made to run (although I think Chevman32 could do even better with a different carb). I have been one of those who has said bad things concerning the Rochester B's, but with lots of experience. We used to restore a few here in the shop (never many, because the cost was WAY TOO HIGH for any except those building show cars); and we could make them work, and work well.......for a while. The absolute metering design of the Rochesters is not bad (although I personally think the Carter, Stromberg and Zenith are superior). Crazyfish - the Zenith to which I refer is the USA-built Zenith, not the all pot metal British version you mentioned. The problem of the Rochester B arises in the use of only 4 screws holding the airhorn to the bowl. This leads to warpage. For best results, the warpage MUST be removed. This is done using heat and pressure, never the removal of metal. This process is labor intensive, and thus drives up the cost of the restoration. The problem is that the warpage reoccurs after a few years. And then has to be straightened again!!! I am just lazy enough to believe that a carburetor should deliver at least 100,000 miles of trouble-free operation, assuming the operator changes the air and fuel filters at recommended intervals. The above sentance does not describe the Rochester B.

Oh, and to emphasize that last point, I put a Carter AFB on my six cylinder shop truck of a different brand when I bought the truck used at 140,000 miles. The truck logged another 400,000 WITH NO CARBURETOR SERVICE before the Missouri rust bugs ate the body the third time; and we retired the truck.

Do it right once, and then enjoy it!

Jon.

Nice post Jon,
Makes me start thinking again about the three Carters Quads I got off ebay with the intent of building one working one.

Hmmmmm......so much to do.

EFI !! I got tired of always fooling with the Carb. I Installed a GM throttle body and haven't had a single problem since...
but really Carter is the way to go if it's got to be carburated "hope I spelled that right"
Good luck