Carb Question

[Nima]

First of all, thanks for all the info about my previous thread about interior/exterior colors. I am amazes how detailed some of them was.
Now, this weekend I plan to do some basic maintenance and one of them is seriving/adjusting the carburator. I have a 327 engine with 2 barrel Rochester on it which previous owner put it on therefore I don't know if it is original. My problem is engine stalls for couple of seconds when I press the Gas but recovers shortly. It works fine on idle or after intial stall. It starts perfect too. Any ideas?

[MACKL]

It sounds to me like the accelerator pump is weak or not working. You can do a quick check to determine the condition of the pump. With the engine turned OFF and the air cleaner removed, look down into the throat of the carb with a light. Now open the throtle at a slow to moderate speed. You should see a continious "squirt" of fuel into the venturi of the carb as you open the throtle. It is ok if the "squirt" peters out toward the end of the throtle movement. But it must be strong at the begining and middle areas. If it is weak, you can replace the pump alone but if you are that far into the carb, you should go ahead and perform a complete rebuild. You may also want to check your vacuum advance on the distributor to make sure it works. It will cause a lack of acceleration as well. Hope this helps!!!

[Nima]

Thanks for the tip. I'll try it.

[9footfan]

nima-i just replaced defective vacuum advance on my 67s 283 with a rebuilt rochester 2bbl that was having same trbl. truck runs great now w/no hesitation. let us know what you find.

[Nima]

I didn't get a chance to work on it today. I'll try it tomorrow and let you know. Thanks for info thogh. By the way, I never rebuild a carb before. Is it too difficult?

[9footfan]

if you don't have any experience rebuilding carbs i and you really want to try i suggest purchasing a newly rebuilt one from someone like jc whitney or lmc truck. i've been very impressed with both of the carbs i've purchased from each one of those suppliers. when you make your purchase have your carb id # from the one on your truck now and purchase an extra rebuild kit with your new carb. when you get your new carb install it and take the old one off. use the kit to rebuild the old one. take your time and have patience. this way your truck runs,you gain some experience with your carb(s), and eventually you will have a backup carb. i do suggest trying the rebuild though you can take the carb to a reputable carb shop who should not have any problems with your carb. i personally have screwed up most of my carbs at least once before i get it right. so what i tend to prefer now is let a pro rebuild it and use my spare while the other carb is in the shop. if your 67 c-20 is a six cylinder it should have a 1bbl carb and these are the absolute easiest to rebuild and you may want to try the rebuild yourself. if you have a 283 v-8 you should have a rochester 2bbl, if a 327 v-8 it should have a 4bbl. good luck have fun and patience!

[Nima]

If I need to buy another carb to keep my truck running while I rebuild this one (which make sence, since I don't have any experience), isn't it better to buy an upgraded carb such as edlebrock 4bb 600-650cfm ? ofcourse if I can afford it!.
By the way, what it the difference between manual choke and electric choke? Can they be replaced instead of each other?

[Nelson]

If you have a digital camera, take lots of pic for reference. I just rebuilt my first carb last week, and the pics help alot. The carb wasn't a Rocherster thou, its was a Holley Q-Jet 4bbl. Good luck!

[72C203503ONTHETREE]

Rebuilding a carb is easy, I even rebuilt some Japanese carbs and those are difficult with all the ball bearings. Q Jets are so simple a first timer can do them in a day easy. The two barrel Rochester is even easier since theres less parts to worry about. Just make sure you use the right gaskets and dont lose the accelerator pump check ball. It would be easier and better to upgrade to a new four barrel and intake but that will cost $400($120-150 for intake, $220 or so for a carb, and the rest for gaskets and other things). If you can find a used one in good shape on e bay you can get it for half price.