JRX111

Hi all,
(Stock Nikki) After sitting for a few weeks I took it out for a drive - after a mile or so it bogged down, ran really rough and died. Pulled air cleaner off and tried restarting- noticed fuel pooling a little on top of both secondary butterflies. Was finally able to start it and drive it home but if I let off the throttle pedal completely it would die. Ran really rough and blew lots of white smoke with a little blue mixed in. Thinking it was time for a carb rebuild I went ahead and did it (Adkins rotary kit). Tried to be careful about float adjust. The floats seemed ok so I reused them. Unfortunately same problem when I got it all together- when I got it to start it ran ok for maybe half a minute then ran rough, bogged down and died - lots of white smoke. Was hard to see in the sight glasses. Seemed like for both bowls either the glasses were fully covered or fully uncovered.... I just couldn’t see a line showing a fuel level. Thoughts? Thanks for any advice!

GSLSEforme

Seems you may not have identified cause of original problem. Did you check the fuel filter for dirt/rust or change it when you rebuilt the carb? Was there signs of dirt in carb on disassembly,how far did you disassemble carb,how did you clean it?Does car have full rats nest/all emissions equipment?
Did you reuse the original needles and seats or replace with what came in the kit,did you save the originals? Did you attempt to adjust the floats,reason being,factory set floats are near 100% right on til someone adjusts them...Pull dipstick,does oil smell like gas,what condition are spark plugs?

How about some history on the car,miles,etc... where in Md are you located?

mazdaverx713b

iTrader: (91)

When the floats stick in the float bowls, the carb will fill up with gas. Nothing else that I can think of will cause that issue. Unless I suppose, you have a cracked or dented float and gas is able to continue to fill the bowls as the floats are not rising properly.

JRX111

Thanks much for the replies....(to GSLSEFForme, I’m in Catonsville). Some more details- my FB has 95,000 miles and still has all stock emissions and rats nest. Fuel I’m sure is a little stale (about 4 mos old) but doesn’t seem too bad to me. I used the new float needles and seats from the Atkins kit but reused the old crush washers. One thing that I wonder about is that after engine shutdown when I looked at the float bowls it appeared that both floats were below the sight glasses. Not sure if that’s a symptom that the floats are stuck, or bad. They are 36 yr old floats but during the rebuild they seemed empty and I could see no bubbles when I submerged them. The float measurements with respect to the air horn were in spec. I’m wondering if the significant fuel pooling on top of the secondary butterfly valves is a key symptom. If it’s a stuck float is there a trick to installing them so they don’t stick?

GSLSEforme

If you have the original needles/seats reinstall them. Again,float adjustment from factory 99.99% of time is correct and needs no adjustment. Replacement needles/seats in most of these rebuild kits are of poor quality,poorly machined and can cause symptoms you are experiencing.
Readjusting floats can be a painstaking process. Float height is correct when fuel level is 1/2 way up sight glass.
Usually dirt/rust is responsible for initial flooding in carb. What did you find in carb when disassembled,did you check contents of fuel filter and replace it? As these cars age,rust and gunk in fuel tank becomes an issue. Gas in oil,plugs fouled?