Nikki carb floods, running rich

DIT

MEMBER
1991 MAZDA B2200
186,000 MILES

Hey, hope this works and is actually free. Been working on my 91 b2200 carburator, have done many things and all seem to be in good order. EXCEPT, she starts fine cold, fast idle no problem, float level fine, but when I blip the idle to kick it down, the float bowl immediately fills up and starts running rich; black smoke, rough idle etc. Ideas?

Monday, September 17th, 2012 AT 12:43 AM

5 Replies

ASEMASTER6371

MECHANIC
52,796 POSTS

Make sure the needle valve and seat are tight in the body. Did you blow out all the vents? Did you soak it in carb cleaner? Is the float copper or plastic and did you replace it?

Roy

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Monday, September 17th, 2012 AT 12:46 AM

DIT

MEMBER
3 POSTS

Hey great, thanks for the quick response. Rebuilt the carb a few years back, most recently had it off completely once and have taken the top off more times than I can count to blow out all the ports and such, has plastic float which I recently put the old one I had from the rebuild back on, same with the float needle. Pulled out the air mix screw and blew that out as well with carb cleaner. The only lead I have right now is that perhaps the fuel pressure could be too high, dont have a way to test it.

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Monday, September 17th, 2012 AT 12:56 AM

CJ MEDEVAC

MECHANIC
11,004 POSTS

THIS WORKS FOR ME. SEE MY PICS

IT WAS ABOUT $12 FOR THE GAUGE--THE REGULATOR WAS MAYBE.$20

THIS IS ON MY '77 JEEP CJ 5 258 CID STRAIGHT 6 W/ A HOLLEY 390 4 BBL ON IT. OTHER IS A '46 WILLYS

MY PICS WERE INTENDED TO AID THE CJer IN GETTING STUFF BACK CORRECT---WHOSE JEEP HAS BEEN RIGGED OVER THE PAST YEARS 26-36 YEARS. SOMETIMES DUMMIES START BY ELIMINATING THE RETURN TO THE TANK (MAYBE BECAUSE A "IN AND OUT" FILTER IS CHEAPER?). THE ORIGINAL SET-UP RELIEVES TOO MUCH PRESSURE GOING TO THE CARB

I'M MOSTLY IN TUNE WITH THE CJs, I HAVE ANSWERED MOST SINCE JAN 2010 HERE AT 2CAR.I'VE MADE LOTS OF PICS

MAYBE YOU NEED A CJ?

I ANSWERED YOU SINCE I HAVE SOME BASIC CARB EXPERIENCE

DOES YOUR FLOAT HAVE FUEL INSIDE OF IT?

THE PRESSURE GOING IN SHOULD BE THE 1ST THING YOU CHECK

NEED MORE INFO?--LET ME KNOW

THE MEDIC

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Monday, September 17th, 2012 AT 1:32 AM

DIT

MEMBER
3 POSTS

Hey there. Looks like I got it, replying to this post for anyone who ends up having this same problem. Turns out it was what is being called the slow fuel cut solenoid. It was shot, got one at a junkyard and she runs great now. Good info on this carb here;
http://www.mazdatrucking.com/B2200/OEMCarb.html
Also turns out I may have an 81 CJ with a pacmule trailer available to me in the near future so funny you should mention it. Remember; feedback carburators are fun! Good luck!

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Wednesday, September 19th, 2012 AT 1:51 PM

CJ MEDEVAC

MECHANIC
11,004 POSTS

GLAD YOU GOT IT!

YOUR CARB IS A BIT MORE COMPLICATED THAN A CJ

MAYBE YOU OUGHTA SWAP THE MAZDA FOR THE CJ?

ANY CJ QUESTIONS, JUST POST 'EM

THE MEDIC

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