FAJS CARB Won't run
05-22-20, 03:17 PM
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FAJS CARB Won't run
The Weber Knockoff (48 DCOE) floods with gas coming out both horns. then car stops running like it runs out of gas. What do you think my problem maybe? the car actually start running with the gas flooding from Horns.
05-22-20, 03:40 PM
#2
Sounds like it stops because there's too much gas.
Likely the floats are stuck, or they're not set at the correct height. Get the fuel to quit spilling out first.
There's a couple of Weber books in PDF form at the bottom of the manuals section at foxed.ca , they'll show how to set the float height.
Likely the floats are stuck, or they're not set at the correct height. Get the fuel to quit spilling out first.
There's a couple of Weber books in PDF form at the bottom of the manuals section at foxed.ca , they'll show how to set the float height.
05-22-20, 03:45 PM
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if it drips from the horns with the fuel pump running, the float level is too high. you should be able to have the fuel pump on, with the engine not running it should not drip, if you push on the fender or rock the car, a drip is acceptable.
05-23-20, 10:15 PM
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. Thank you. I will look at the float and verify the settings. The FAJS 48 DCOE carb is idling but won't progress from idle to full operation. Carb chokes out and acts likes it's starving for gas. Any thoughts?
05-24-20, 08:14 AM
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05-24-20, 02:02 PM
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did you fix the gas coming form the horns? that is first. then you start with the idle and work your way up to full throttle.
with the correct float level, see dripping from the horns, the idle screw half turn out is about right. this is telling you that the idle jet is about right.
with the correct float level, see dripping from the horns, the idle screw half turn out is about right. this is telling you that the idle jet is about right.
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05-25-20, 07:25 PM
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j9fdI3s, I took the top off the carb and found the needle valve was loose. The needle valve was so loose it hindered the movement of the float. The float's pin is very loose and can move from side to side. I can't find the right float adjustment for the 48 DCOE but will continue to search. Hopefully, this will fix the flooding and the progressing issue.
05-26-20, 10:08 AM
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j9fdI3s, I took the top off the carb and found the needle valve was loose. The needle valve was so loose it hindered the movement of the float. The float's pin is very loose and can move from side to side. I can't find the right float adjustment for the 48 DCOE but will continue to search. Hopefully, this will fix the flooding and the progressing issue.
05-26-20, 11:59 AM
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j9fdI3s,
I put it back together this morning and it work great. Car started, idle, progress from idle to run fine. I was able to test drive the car for the first time. It ran good. No more flooding. It gave a few drops from the horns when I shut it down. Thank you for your guidance and expert help. I will continue to tune as I test drive.
I put it back together this morning and it work great. Car started, idle, progress from idle to run fine. I was able to test drive the car for the first time. It ran good. No more flooding. It gave a few drops from the horns when I shut it down. Thank you for your guidance and expert help. I will continue to tune as I test drive.
05-26-20, 07:32 PM
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sweet! tuning these things is a process, and it can be kind of long, but when its dialed, it'll pretty much stay that was
05-26-20, 08:01 PM
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I took a test drive and what I thought was a rattle is carb spitting and coughing. If I easy off the gas it goes away and if I try to accelerate the rattle and beat the band noise comes back. It sounds like a loose exhaust pipe beating the car from underneath. What you think?
05-27-20, 09:37 AM
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that is not good. you might check for stuff that is physically loose, but if not it is probably too lean
05-31-20, 08:40 AM
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I adjusted the mixture screws from a half turn out to one whole turn out. The car accelerate more freely with less spitting and knocking of the carb. Car idles smoothly and without any intervention. It struggles with load from acceleration and going up hills. I will continue to make small mixture screws adjustments to eliminated bogging of carb performance.
05-31-20, 09:02 AM
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next step is to pull the jets, see what they are and order bigger ones
05-31-20, 02:22 PM
#17
I have an IDA I'm putting on my new motor when it goes in. I poured through all the threads I could find here on RX7club.com until I found what worked best for the same 48IDA on a similar build as mine (engine size, port style, gearing, etc).
I can tell you the stock carb jetting is absolutely not right for your motor and you are in a crash-course of carb tuning. Google as much as you can on that carb (the Weber carb it is cloned from) and copy what worked for others with the same engine/exhaust as you. That will be an excellent baseline to start from. 100's of other rx7 owners have done the ground work for you already... find the threads and copy what worked for them. Fine tune from there.
This can be very frustrating but in the end it will make you a better (home) mechanic and give you that "I built it myself" satisfaction.
I can tell you the stock carb jetting is absolutely not right for your motor and you are in a crash-course of carb tuning. Google as much as you can on that carb (the Weber carb it is cloned from) and copy what worked for others with the same engine/exhaust as you. That will be an excellent baseline to start from. 100's of other rx7 owners have done the ground work for you already... find the threads and copy what worked for them. Fine tune from there.
This can be very frustrating but in the end it will make you a better (home) mechanic and give you that "I built it myself" satisfaction.
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