The Stovebolt Site Forums The Shop Area Engine Shop Carburetor Problem

I was having problems with my Rochestor carburetor after a rebuild. I had several recommendations from you guys. I finally got to work on it 4/23/07. I used some fine sandpaper to polish the power piston and the hole. I took a small wire and cleaned out the four holes in the throttle body. I blew them out with air. I adjusted the float so it would have to move up 1/16 inches higher that the specs. I noticed that the gasket between the carbureter and the intake manifold was blocking a hole in the throttle body. I cut it so it would allow a vacuum to be pulled on that hole. I reassembled and put the carburetor back on the engine. I cranked it and with a few adjustments I got it to idle. It is still running rough. I'll have to make more repairs on it. At least the carburetor seems to be working OK. Thanks to all that contributed ideas.
Melvin

You may have to remove your spark plugs & clean them. Running rich will put black soot on the plugs & make it run rough.

Wrenchbender Ret. Thanks for all the help. I'll have to clean or replace the plugs and check the points. Then I will have to check the timing. I need to have the valves adjusted. I don't know how to do that, so I'll have to find a mechanic that can do it. Thanks

I'll take a stab at it. It's been years since I've rebuilt a carb. and they were of the four barrel type. My 61 Apache's model "B" (manual choke) Rochester was leaking gas so I rebuilt it and everything works great now, amazingly. However during assembly when I got to the part of the flange gasket "between the carb and intake" the instructions say "chevrolet 6 cyl. with heat insulator block does not require a flange gasket. Mine had the block so I did not use the gasket. Are all of them "6 cyl" designed to have the block. It seems the additional heigth of the carb. would not only keep heat off it but possible allow for more of a venturi effect for the draw of fuel for idling.

I need to have the valves adjusted. I don't know how to do that, so I'll have to find a mechanic that can do it. Thanks [/QB][/QUOTE]

You can adjust the valves yourself. There has been plenty of posts on this. Do a search & if you have anymore questions post them & we will help.

side shot of dad\'s 1953 half ton chevy truck


I found this in the Tech Tips:


http://www.stovebolt.com/faq.html#valves

http://www.stovebolt.com/techtips/valveadjustment.htm


do those cover everything?

then there is the '57 shop manual :


http://www.stovebolt.com/bboard/cgi-bin//ultimatebb.cgi?ubb=get_topic;f=2;t=013444#000004


What are we missing?

-W