The Stovebolt Site Forums The Shop Area Engine Shop rebuilt rochester

I'm new to the stovebolt page and could sure use some help with my rochester problem. I've got a 1958 chevy 3100 with 235 inline six, I just rebuilt a rochester model b because of the inability to start the truck without using starting fluid. After rebuilding and replacing the carb I still can't get the thing to start without adding gas manually or spraying in some starting fluid. I have seen in other postings that another option is to go with a tom langdon holley weber carb or a carter yf, any suggestions?

welcome to the shop Frank - if you fiddled the carb and the problem hasn't changed, have you checked everything else? like ignition resistor, and the bypassing of it when starter's engaged? is it cranking at a decent speed or slow? fuel pump supplying a good flow?

the only time I've had any problems starting w/ the rochester is when the truck sits long enuff, the carb goes dry, but full choke and lotsa pumps on the pedal always works pretty quick

Bill

These carburetors generally work fine and are used on thousands of OEM applications. You should only have to choke it once and fire it up. You may have other problems such as the ignition system, timing, plugs, wires, and/or compression. Also, check the fuel pump pressure and the filter. I would go lightly with the starting fluid unless you are trying to start it in sub zero temperatures, that stuff is volatile and can cause more problems than it helps. After checking the aforementioned, I would take another look at the carb and make sure everything went back in the correct order. It has 2 balls of different sizes and it won't run with them mixed up. I hope this helps, Fred

Might not be a bad idea to check the plugs for fouling, either. I'd suspect some sort of spark gremlin, or possibly compression, before going for carb/manifold swaps.
If the ignition checks out, check to make sure that the accellerator pump works in the carb, shoul have a solid stream when the throttle is actuated.

CALIPATRIA! We used to get off the train there in route to Brawley!

If it runs by pouring in gas, it has a bad pump, clogged fuel line, old gas or crap in the tank etc. I've seen guys make a little temp gas tank with a gas can/hose going straight into the carb, should make it run. Don't set it on fire!

Thanks for the suggestions fellas, I will get a chance to tinker with the truck over the holiday weekend. The one thing that I did notice the other night was that I was not getting a prime for starting. I guess that the carb must still be dirty, anyone dealt with a carb that wouldn't prime? Thanks

What you refere to as prime is called the accelerator pump. Look down the throat of the carb & move the throttle. You should get a squirt of gas each time you open the throttle. If not you need to go back into the carb. It could be like rfs says if you mix up those balls it won,t work & can ruin the carb. if you can,t get it out.

Also check float level, may be too low.

To answer your question about Langdon's Holly/Weber 5200 carb/adaptor/linkage....I have one on my stock 235 and it eliminated all the typical problems you encounter with a Rochester.

My truck is driven daily, the engine has good compression, was starting and running fine but was leak-prone and throttle shaft was sloppy. Typical idle problems and driveability wasn't up to par. The Holly/Weber, out of the box, eliminated all my carb problems, improved my mileage, and makes it a pleasure to drive.

Once you've followed the guys suggestions and have a sound engine with good compression, IMHO you would find the Holly/Weber a vast improvement over the Rochester. Hope this helps.

Happy New Year everyone!! After a weekend of tearing apart the rochester, it seems as though I may have gotten to the problem(s). I guess that when I rebuilt the carb, I never paid really close attention to a tiny hole coming from the vicinity of the power piston. As a result I never noticed that it was dirty and not allowing any fuel to be pumped in for start up. So after some really close observation, I was able to identify and clean that little port. I thought that I was done. So I rebuilt the carb again and reistalled it back on the intake. It started up instantly!! I allowed it to warm up and made some adjustments to idle and air fuel mixture and got it running pretty well. I took it out for a drive around town and was surprised that it ran so well. I got back home and relaxed the rest of the day. Later that evening, feeling really good because the carb problem had been all resolved, I tried to start the truck again. Well the carb was not quite done with me. It turns out that the carb was flooding all over the intake and exhaust. After sleeping on what had happened, I took the rochester apart for what was probably the 10th time in a week. After close observation and measuring the float drop, checking for debris that could have made the carb flood, I was at a loss. Then I grabbed the float and placed it in the full fuel bowl to see if maybe it was sticking somewhere on the sides. I got it!! One of the floats had a tiny hole and had filled with fuel, so it sank down to the bottom of the fuel bowl, so of coarse the valve was going to continue to think that there was no fuel in the fuel bowl. After replacing the float with another float from one of my other donors, I rebuilt the rochester again. I installed it back on the intake and it started right up and no longer flooded!!!!! Victory was mine!! Anyway, thanks to everyone that took the time to post a reply, I am pretty sure that this will not be the last time that I ask for help.

Hey Frank; Nice going. That's what I call stickin' to it! I have a "B" on my 235, carefully rebuilt it and set it up, haven't had any problems for 6 months now. Starts right up (unless it's been sitting for a week, then it takes some pumping) idles good, accelerates good. Don't know why this carb has such a bad rep.