Author Topic: nikki two barrel carb problems  (Read 2872 times)

0 Members and 1 Guest are viewing this topic.

Offline crazycraftsman

  • Turf Warrior
  • **
  • Posts: 864
  • Karma: 1
  • Gender: Male
    • View Profile
    • owen
nikki two barrel carb problems
« on: July 21, 2014, 11:02:55 PM »
My carb has a aluminum bowl with all lows and high side jets in bowl. Adjustable low needles on top,straight up coming down. Two 12mm plugs in bowl over mains. I need a carb kit and can't find part numbers. It's of a 35 cube vanny i was told. Ive looked up tons of repair manuals online and can't seem to find the right one. Need a needle , bowl gasket and float. Worth a try runnung like    . Any help would be great.Thanks
owen


owen
Lawnmower Racing in B.C   Canada
www.lawnmowerracingfv@blogspot.com
WMWS points cup winner BP 2016

Offline crazycraftsman

  • Turf Warrior
  • **
  • Posts: 864
  • Karma: 1
  • Gender: Male
    • View Profile
    • owen
Re: nikki two barrel carb
« Reply #1 on: July 22, 2014, 07:01:23 PM »
Found the carb kit and ordered it. 90 bucks. get the rebuild kit tommorrow . My vanny is running rich and puffing out black randomly  .What inside carb could cause it to do this all of a sudden. Cleaned and cleaned it and all holes,jets  seem good. Any ideas of the problem ?
Owen.
owen
Lawnmower Racing in B.C   Canada
www.lawnmowerracingfv@blogspot.com
WMWS points cup winner BP 2016

Offline BIG AL 202

  • Highly Mowtivated
  • ****
  • Posts: 3126
  • Karma: 8
  • Gender: Male
  • LET'S GO FIND A NEW PLACE TO RACE MOWERS!
    • View Profile
Re: nikki two barrel carb problems
« Reply #2 on: July 22, 2014, 08:16:22 PM »
FLOAT LEVEL
ALWAYS VOTE FOR ED!   FONGS BROTHER FROM ANOTHER MOTHER!


Offline crazycraftsman

  • Turf Warrior
  • **
  • Posts: 864
  • Karma: 1
  • Gender: Male
    • View Profile
    • owen
Re: nikki two barrel carb problems
« Reply #3 on: July 22, 2014, 10:54:15 PM »
Thanks for the reply big al . It's plastic and is not adjustable. Needle does not seem to be sticking at all and needle is only one piece not like the later style. Do these have problems with the rubber float bowl gasket cross leaking? There,s 2  welch plugs on top of carb for the lows? should i take them out,clean and replace or will they have anything to do with a rich issue? Thanks for any help hopfully this rebuild kit fixes it. lost a bunch of points last week in the twin class and racing this saturday.
owen
Lawnmower Racing in B.C   Canada
www.lawnmowerracingfv@blogspot.com
WMWS points cup winner BP 2016

Offline Jim Knutson

  • Mow-Forum Junkie
  • ***
  • Posts: 1320
  • Karma: 10
  • Gender: Male
  • i didnt break it......i modified it!
    • View Profile
Re: nikki two barrel carb problems
« Reply #4 on: July 23, 2014, 07:32:53 AM »
Is it the oval 2 screw aluminum bowl, or the 4 sc4ew rectangle looking bowl?
If you quit when you're behind, you will never win.

Offline crazycraftsman

  • Turf Warrior
  • **
  • Posts: 864
  • Karma: 1
  • Gender: Male
    • View Profile
    • owen
Re: nikki two barrel carb problems
« Reply #5 on: July 23, 2014, 08:20:55 AM »
4 bolt .
owen
Lawnmower Racing in B.C   Canada
www.lawnmowerracingfv@blogspot.com
WMWS points cup winner BP 2016

Offline Jim Knutson

  • Mow-Forum Junkie
  • ***
  • Posts: 1320
  • Karma: 10
  • Gender: Male
  • i didnt break it......i modified it!
    • View Profile
Re: nikki two barrel carb problems
« Reply #6 on: July 23, 2014, 03:03:02 PM »
The rubber gasket for those has to be in perfect shape, or else....I actually preffer the nikki with the tin 2 screw bowl, much easier to deal with, and plenty adequate.
If you quit when you're behind, you will never win.


Offline crazycraftsman

  • Turf Warrior
  • **
  • Posts: 864
  • Karma: 1
  • Gender: Male
    • View Profile
    • owen
Re: nikki two barrel carb problems
« Reply #7 on: July 23, 2014, 10:55:24 PM »
Got a back up carb from my buddy,the competition. When i received my carb kit it shows two different main jets, then found one has a larger feed hole in it then the other main jet. Then found out i put it on the wrong side. lol Why is there two different size main jets?R and L, in the nikki carbs.35 and 38 cube vanny and intec carbs. The intake looks same length left to right. WHY?
owen
owen
Lawnmower Racing in B.C   Canada
www.lawnmowerracingfv@blogspot.com
WMWS points cup winner BP 2016

Offline Jim Knutson

  • Mow-Forum Junkie
  • ***
  • Posts: 1320
  • Karma: 10
  • Gender: Male
  • i didnt break it......i modified it!
    • View Profile
Re: nikki two barrel carb problems
« Reply #8 on: July 23, 2014, 11:03:11 PM »
They are close in length, but 1 leg is slightly longer, to accomidate the cylinder offset for crank journal alignment of connecting rods. I make them equal jetting, and forget it....or use the nikki with steel bowl, and high side needle, both cylinders get same mixture.
If you quit when you're behind, you will never win.

Offline more4les

  • Mow-Forum Junkie
  • ***
  • Posts: 1212
  • Karma: 15
  • Gender: Male
  • FatBoyZ Racing - Mowin' Down the Competition!
    • View Profile
    • Northern  NY Lawn Mower Racing
Re: nikki two barrel carb problems
« Reply #9 on: July 24, 2014, 07:43:20 AM »
Fuel is naturally pulled to the bottom cylinder by gravity so it will run richer than the top. So they use a smaller jet to the bottom cylinder. At higher rpm it is less prevalent so equal jetting works as well. There are other things that can be done to take advantage of this extra fuel....

Lester 
2012 & 2014 Sportsman Champion (Builder/Owner), 2013 2nd.
2011 - 2014 Pro-Mod Champion, 2011, 2014 2nd Builder/Owner
2008-2013 Pro-Stock Champion (2009-13 Builder/Owner)
2007 Pro-Mod Champion
Founder of NNYLMR
http://sports.groups.yahoo.com/group/NNYLMR/
Front Yard Chassis
Impact Racing Engines
http://www.facebook.com/groups/NNYLMR/
SKYPE ME: more4les

Offline crazycraftsman

  • Turf Warrior
  • **
  • Posts: 864
  • Karma: 1
  • Gender: Male
    • View Profile
    • owen
Re: nikki two barrel carb problems
« Reply #10 on: July 24, 2014, 10:04:43 PM »
Thanks Jim and Lester for the info and explaining it. I put the back up carb and installed kit in it. Runs way better. I found the metal 2 screw bowl with black feed  tube in it. I got some gaskets coming for it and will swap my throttle to other side of engine next week. Has anyone made 2 adjustable jets for the mains on the 4 screw carb. I like the thought of being able to adjust highs and lows.
owen
owen
Lawnmower Racing in B.C   Canada
www.lawnmowerracingfv@blogspot.com
WMWS points cup winner BP 2016

Offline crazycraftsman

  • Turf Warrior
  • **
  • Posts: 864
  • Karma: 1
  • Gender: Male
    • View Profile
    • owen
Re: nikki two barrel carb problems
« Reply #11 on: July 25, 2014, 10:43:17 PM »
Thanks for the info. Went to test the newer carb out, made it one lap and the right side welch plug fell out. Just my luck. Lol . Got a new one in. What sealent do you guys use over welch plugs ? Seal all?
Thanks
Owen
owen
Lawnmower Racing in B.C   Canada
www.lawnmowerracingfv@blogspot.com
WMWS points cup winner BP 2016

Offline crazycraftsman

  • Turf Warrior
  • **
  • Posts: 864
  • Karma: 1
  • Gender: Male
    • View Profile
    • owen
Re: nikki two barrel carb problems
« Reply #12 on: July 27, 2014, 09:36:25 AM »
After getting the carb welch plugs sealed . I went out and tested it and it ran crappy again. Coughing and wanting to try and stall coming off throttle. My pump with line off pumped a nice stream of gas but I guess not enough.  My problem ended up being the fuel pump.Took the aluminum pump apart and the pulse diaphragm was sucked in on one side. I guess it was sucking gas to intake pulse , then showing plugs rich. Runs perfect now.
owen
owen
Lawnmower Racing in B.C   Canada
www.lawnmowerracingfv@blogspot.com
WMWS points cup winner BP 2016