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66x3 06-28-2021 11:49 AM

Rochester two barrel
 
My 66 283 sometimes dumps fuel onto intake after being parked after driving. Float sticking? I'm sure carb needs rebuilt but curious as to what's going on with it. Seems to run ok without a lot of hesitation or missing.

notsolo 06-28-2021 12:10 PM

Re: Rochester two barrel
 
Yep, float sticks open and fuel comes out the top angled tube you see near the center air cleaner bolt. Not to bad taking the top of carb off to clean.

66x3 06-28-2021 06:07 PM

Re: Rochester two barrel
 
Yep, thanks . Picked up a rebuild kit from napa today.

geezer#99 06-28-2021 07:25 PM

Re: Rochester two barrel
 
Are you sure it’s not just the fuel boiling in the bowl.
Might need a heat insulator.

AcampoDave 06-28-2021 07:36 PM

Re: Rochester two barrel
 
Quote:

Originally Posted by geezer#99 (Post 8937901)
Are you sure it’s not just the fuel boiling in the bowl.
Might need a heat insulator.

this reminds me....
My 283 has the two exhaust ports on the intake flange and the carb has a cast Iron base which gets plenty hot too. An application like mine even requires a special carb base gasket which is constructed like an exhaust manifold gasket. If I ever remove the intake, I think Im going to block those holes off. I doubt they do me much good in California anyhow.

geezer#99 06-28-2021 08:12 PM

Re: Rochester two barrel
 
Quote:

Originally Posted by AcampoDave (Post 8937905)
this reminds me....
My 283 has the two exhaust ports on the intake flange and the carb has a cast Iron base which gets plenty hot too. An application like mine even requires a special carb base gasket which is constructed like an exhaust manifold gasket. If I ever remove the intake, I think Im going to block those holes off. I doubt they do me much good in California anyhow.

They called that the hot slot intake.
Used on 2 and 4bbl intakes.
And it does need a sandwiched gasket with a metal plate.

66x3 06-28-2021 11:25 PM

Re: Rochester two barrel
 
The carb does have the cast iron base. I have had the carb off before but don't believe it had an insulator along with the gasket but that is sure something to think about. Anybody know of a place I could get one? Thinking probably napa and ask them to look for one for maybe a C60 327 with two barrel. Also it did not used to have this issue, quite possibly until after i had carb off so maybe operator error!

geezer#99 06-29-2021 08:14 AM

Re: Rochester two barrel
 
Look here.
This one is for the small base carb.
Search on there if yours is the big base carb.



http://hotrodcarbs.com/store/small-b...nsulating.html

66x3 06-29-2021 08:30 AM

Re: Rochester two barrel
 
Man thats pricey for just an insulator! Glad I don't have three deuces! But I guess if ya need it ya need it. I know for sure there wasn't one on there before, maybe today's gas. Isn't the big base carb the later model rochester two barrel?

geezer#99 06-29-2021 08:51 AM

Re: Rochester two barrel
 
I don’t know which you have.
Yup they aren’t cheap.
Depends on what your time is worth and your available tools.
I made my first heat spacer from a piece of 3/4 inch oak. Wood is the best insulator.
Or look for heat insulating material at the hardware store and make a gasket.

Or look here.



https://www.carburetor-parts.com/Gaskets_c_572.html

Or here.



https://quadrajetparts.com/rochester..._80_82_97.html

vince1 06-29-2021 08:53 AM

Re: Rochester two barrel
 
Make sure your tank is not pressurizing. Some of the caps they sell only vent one way.

AcampoDave 06-29-2021 09:35 AM

Re: Rochester two barrel
 
Maybe it's just getting old and after you rebuild it, it will work fine.

66x3 06-29-2021 11:32 AM

Re: Rochester two barrel
 
Ok guys, thoughts on this. Digging through old parts stash found an aluminum carb adapter from old style rochester to a bigger two barrel ,not sure what. Looks like this would also work as a spacer between manifold and carb . Need a gasket between manifold and spacer and another between spacer and carb, correct? Checked to make sure all lines, linkage etc. clears. I appreciate the help

AcampoDave 06-29-2021 08:20 PM

Re: Rochester two barrel
 
Quote:

Originally Posted by 66x3 (Post 8938158)
Ok guys, thoughts on this. Digging through old parts stash found an aluminum carb adapter from old style rochester to a bigger two barrel ,not sure what. Looks like this would also work as a spacer between manifold and carb . Need a gasket between manifold and spacer and another between spacer and carb, correct? Checked to make sure all lines, linkage etc. clears. I appreciate the help

my 283 runs fine without a spacer of any kind and it's a "hot slot" manifold. I would rebuild the carb first and try it out before improvising.

66x3 06-29-2021 11:27 PM

Re: Rochester two barrel
 
Yes, you are right. I'll rebuild and go from there. But a question- what is a " hot slot" manifold ?

geezer#99 06-30-2021 12:13 AM

Re: Rochester two barrel
 
Try this.


https://www.67-72chevytrucks.com/vbo...d.php?t=762751

66x3 06-30-2021 10:38 PM

Re: Rochester two barrel
 
I do have the "hot slots" in the carb base and in the manifold about a 1/2" hole on each side which I guess is the passage for the heat. You can tell on the carb base that the gases have eaten away on it. Interesting information in the threads .I never knew what those holes were for or that they could be a source for vacuum leaks if using the wrong gaskets.

AcampoDave 07-01-2021 06:38 PM

Re: Rochester two barrel
 
I know, I found that to be a suprise on my own manifold too. The first time I pulled my carb I noticed those holes and they were all plugged up with carbon. I should have left them that way but I was pulling the intake anyhow so I had the local engine guy hot tank it for a repaint. I figure the most effective way to block them is with a high performance intake gasket which seals off the crossover port on the heads like this... https://www.summitracing.com/parts/f...hoClMEQAvD_BwE and I would do it too but (apart from needing a new carb base gasket every now and then), it really runs just fine like that.

66x3 07-01-2021 10:38 PM

Re: Rochester two barrel
 
Well, I haven't rebuilt the rochester yet but think I've found the problem. Some idiot (me) last time had the carb off left the round gasket that goes on the fuel filter inlet off. Pretty sure it still could stand a rebuild but I want to have some fun with the truck this weekend and don't wanna take a chance on truck being down. Went to the local cruise-in yesterday evening, smelled gas all the way home. Got home ,popped the hood and air cleaner and saw gas all over by the inlet. At least I was smart enough to bring my fire ext. with me!

AcampoDave 07-01-2021 10:53 PM

Re: Rochester two barrel
 
Good thing you're not in California. You could have burned the whole state down!


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