THansenite

Hello All

I am new to this board and come needing assistance from carb gurus. Here is my tale:



I have wanted an RX-7 ever since I knew what one was. A couple of months ago, one presented itself for me. It was a 79 RX-7 with a manual transmission. The car didn't run at the time, but for $200, I couldn't say no. So I trailered the car up to my parents' house for me to work on during the weekends. Except for the underbody and the interior, the car is in pretty good condition considering its age.



The first thing I did when I got a chance to work on it was to get a carb rebuild kit. I spent a Saturday cleaning every part with carb cleaner and a toothbrush. I checked the float levels and put it back together with all new gaskets making sure everything was on correctly. I got a new battery and tried firing it up. Lo and behold, it fired and amid much smoking, idled. It was late at night when I finally got it running so I called it a night and figured I would pick up working on it the next day.



I was so excited to finally take it out for a drive the next day. I went out and fired it up. With a rough idle, it was alive. I pushed in the clutch and shifted into reverse. To my surprise, I did a 6in burnout and the car died. No clutch fluid. So I got that taken care of and tried to fire it up again. No luck.



The car has not run since. The only way it will run is if gas is poured through the carb. I have replaced the fuel filter. Fuel is getting to the carb fine. With the fuel lines disconnected from the carb, fuel pumps out with the key on. I can see the fuel is a little over halfway up on the float sight glass. However, no fuel makes it to the venturis. When I press down on the accelerator, there is no squirt of gas.



I have disassembled the carb 4-5 times since. Thoroughly cleaning, checking, and double-checking everything. I have blown carb cleaner through every hole I can find in the carb until the cleaner flows through. I don't know what to do. I am almost ready to buy a used carb to put on. This is a last ditch effort to get the carb working before I take that step.



Sorry for writing a book, but I am desperate to get this car running. I want to feel the power of the rotary. I have had the car for about 3 months and have yet to drive it. Please help a fellow rotary enthusiast. Thank you.

Option6

If it ran before but you're suddenly not getting fuel through the carb, you may have plugged the fuel needles or screen. Did you clean them all while rebuilding your carb? I did the stock Nikki carb on my '79 last March and had to clean out 25 years of sludge. It was at the bottom of the float bowls, coating & plugging the needles, and and the fine mesh screens. Maybe your carb had a stroke and some grunge has blocked up something. I cleaned all the passageways with carb cleaner and compressed air.



If you are really careful not to drop anything down the venturis (I'd stuff a rag down them just to be sure), you could always just pop off the air cleaner and pull out the jets and needles to check them one at a time.



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I'm no carb expert by any stretch of the imagination, but I'm really good at taking stuff apart, cleaning it, and having it still work on reassembly! Hopefully others will have some insight for you too.



Other things to check would be the accelerator pump. Can you get a healthy squirt of fuel by operating the linkage by hand? If you get nothing, your firewall side bowl is either empty (solution: run the car in start for a few seconds), the check ball is blocked, the diaphragm is dried out or torn (due to age or sitting dry for too long), or the accelerator pump circuit or orifices are clogged. I'd check them in that order.



Good info:

http://www.rx7club.com/showthread.ph...hreadid=238028

http://pbandjracing.com/adjusting_th...ator_pump.html

http://www.mazspeed.com/carburetorfacts.htm

http://www.geocities.com/mazdarx05/carby1.htm



Good luck!

j9fd3s

i had the exact thing happen, it turned out to be a peice of air pump stuck in the air control valve causing a HUGE vacuum leak. no vacuum in the intake = no fuel going thru the carb.



if you've been thru the carb and everything looks good, look elsewhere. intake gakset, carb base gasket, the vacuum advance cannisters, acv.....

Rx7carl

You wont see fuel comming out of the venturi at idle. The ports for idle fuel are under the throttle plate.



It wont start if your pumping the throttle either?