Thread: Why do Novi carbs overfuel?
10-12-2007, 02:58 AM #1
Why do Novi carbs overfuel?
Ive just installed 44mm Novi's on a gpr but one carb overfuels badly!!!!! ive swapped the carb from one cylinder to the next with exactly the same result on the next cylinder, and that carb runs soooo rich that it wont even fire and chunders black fuel and oil out the exhaust! Ive put a whole new kit through the carb! Nothing!!! All carbs are set up identical, same highs and lows, same needle and seat, same springs! Ive checked the pop off pressure of them.... All the same! Ive stripped it like 10 times........What the hell is going on?
10-12-2007, 07:40 AM #2
It sounds like you have a bad N/S but you checked the popoff. Sometimes you must double up the clear valve on the kidney to stop this on the tripple pipe boats. What was the popoff set at?
10-12-2007, 07:51 AM #3
check that the needle arm pin is seated properly
sounds like a dribbler, but cause will be a bit harder to track down
10-12-2007, 08:32 AM #4
- Join Date
- Jul 2007
I also had a problem like this. The diaphram was stretched out in the carb. When the motor is started the vibration and turbulance of the motor was sucking the diaphram in holding the N/S wide open. Double check the diaphrams as well and replace them when you go through the carbs.
Like the other guys said, get a popoff gague and check your popoff
10-12-2007, 11:15 PM #5
After many removal and replacments of the problem carb I am pleased to tell you all i have found the problem! And it is a problem that maybe you should all be aware of! Please see the attached pic, and the grub screw marked that blocks the low speed adj gallery........ Well it wasnt there?????? (please dont ask me where it was) hence the large amount of fuel that was being delivered to the cylinder!
But.............. I didnt stop there, I removed the other 2 carbs and found that in both of the other carbs the grub screws were there but were loose! And in my opinion would have been passing a small amount of fuel past the screws!
Could be an issue that a few of you have that have been saying that your carb settings are erratic?
Cheers anyone for the input!
10-13-2007, 02:56 AM #6
Sorry had to post again it wouldnt let me attach it to the last message
Users Browsing this Thread
There are currently 1 users browsing this thread. (0 members and 1 guests)
By pdxrealtor in forum 2-Stroke PerformanceReplies: 4Last Post: 05-11-2008, 12:42 AM
By zrtman in forum Yamaha PWC Performance (2-stroke)Replies: 10Last Post: 01-06-2008, 07:16 PM
By Skips313 in forum Kawasaki Tech Tips and InfoReplies: 0Last Post: 12-23-2007, 08:42 AM
By ABBOTT in forum Yamaha How To & FAQsReplies: 0Last Post: 05-26-2006, 08:09 PM
By ABBOTT in forum Yamaha How To & FAQsReplies: 6Last Post: 01-08-2006, 12:27 PM