Hi, I'm having problems getting the 216 on my 1948 Chevy 3800 (1 ton) to run. When I got the truck it ran, but the carb leaked like crazy out of the accelerator pump, so I threw a rebuild kit and new floats in it. For some reason I just cannot get it to run. It has to have the choke 3/4 closed and the rpm's cranked up, otherwise it just dies. If I back the idle adjust screw to the point of having slop in the throttle blade It will sit and barely run if I'm lucky, eventually dying. As soon as you think about giving it a crack it just dies. The timing has not changed since I got it, advance is working, and I have good spark. The fuel pump got replaced also, and I have confirmed that it is working. I've tried moving the idle mix screw in and out (starting at 1.5 turns out) and it doesn't seem to care what you do to it. I even tried raising the float position a bit to no effect. I have had it apart multiple times now and cannot figure out what is going on with it. Does anybody have any suggestions or thoughts? Thanks.
I dont know what your problem is, but in my opinion your best bet is to search on the web and get some good info and teardown pics on the b carb. Then tear the carb down piece by piece following the breakdown and I am sure you will find what went wrong. Also pay particular attention to the carb spacer and all the ball check valves and gaskets.
There is a 216 group here on the HAMB - http://www.jalopyjournal.com/forum/group.php?groupid=653 - it's slow in there tho. If you don't get a quick response try stovebolt.com or inliners.org ... the stovebolt site is all trucks. They were key in helping me get my 216 running when I was having fuel issues.
Here's what I think with only your information available. Assuming the float level is close, open the idle mixture screw 2 turns from seated position and check for vacuum leaks. Recheck to see if you have the correct carburetor base to manifilod gasket. Sounds like a vacuum leak to me.
Pulled it apart again and gave it a good look over. All passages are free and clear, so the thing really should be pulling fuel through. I was looking at the diagram on this page: http://www.oldcarmanualproject.com/manuals/Carbs/Rochester/B/1951-B/MCarbRoch1951-B_0007.htm and everything seems to be correct, except for I do not have ball check #5 or a detent for one to go into. There is a passage that has a hole coming through the bottom corner of the pump well. When I took it apart there was no ball down there to the best of my knowledge. Page 5 of this service bulletin does not appear to have this ball check valve shown: http://www.newagemetal.com/pages/ServiceProcedures/B/1964/64ModelBmanual.pdf So it looks like they had a couple different designs in regards to this feature? Other than that all ball check valves are in place. The accelerator pump does function though. Any good ideas on checking for vacuum leaks with it not running? Hook up a hose, cap off the carb with my hand and start sucking?