Page 2 of 3
Re: Flooding
Posted: Tue Nov 09, 2010 1:06 pm
by TROUBLED OTTER
superlite wrote:TROUBLED OTTER wrote:The guy who sonic cleaned the carbs set them up as well which is a bit worrying. It runs great when the tank is disconnected and the carbs are running on the fuel that is in them all ready.
I don't want to sound like a smart arse, but unlesss the guy that set them up is familiar with V4 carbs, I'd give them a good going over - NC35 carbs are a law unto themselves when compared with the usual in-line 4s, etc.
I think it's just a case of going over everything and checking the settings against the specs in the Haynes manual (for a start)
You say it runs well when without the tank on - when you've tried this have you had the airbox fully assembled as it should be?
yes, I'm going to check everything again tonight as the bible says.It runs great with the air box on and off.
Thanks again for the help guys.
Re: Flooding
Posted: Tue Nov 09, 2010 1:12 pm
by TROUBLED OTTER
Neosophist wrote:TROUBLED OTTER wrote:I got no problems with stripping the carbs but I just don't understand how carbs work. I did set the floats to 12 mm when I stripped them the first time. The guy who did the carbs has about 40 old fully restored bikes so he seems pritty good at what he does. I'm going to give it one more go tomorrow and have a good look at all the settings again. Do you guys always get these issues with carbs or is it that once there set there set?
The float height is 6.8mm.
How / where are you measuring the float height from.. it sounds like there overfilling and running rubbish, then as the fuel drains out it starts to run better.
I got the float height out of the hainze bible and I am prity sure it said 12mm. I may be wrong though, I will check tonight when I stip it again.I set the height from the edge of the bowl were the gasket sits to the top of the floats.
Thanks again guys for the help.
Re: Flooding
Posted: Wed Nov 10, 2010 6:39 am
by superlite
TROUBLED OTTER wrote:I got the float height out of the hainze bible and I am prity sure it said 12mm. I may be wrong though, I will check tonight when I stip it again.I set the height from the edge of the bowl were the gasket sits to the top of the floats.
12.5 mm for NC35 (12 mm wouldn't give you any ill effects though IMO).
Re: Flooding
Posted: Thu Nov 11, 2010 8:29 am
by TROUBLED OTTER
[img][IMG]
http://i1001.photobucket.com/albums/af1 ... cat009.jpg[/img][/img]
Dont think I can get this any cleaner.Totally stripped the carbs again and checked everything.Float height is spot on 12.5mm.
Put it all back together and got the same result.
When fuel tap is on the on position it floods the carbs and pours out of the overflow tubes.
Turn tap to off position and she runs spot on, Tick over 1000rpm,no flat spots on reving or hunting.Then it uses all the fuel in the carbs and stops.
I checked the oil cos I was a bit worryed about petrol in the sump after flooding and theres loads in there so will have to drop the oil tonight.
I thought it may have been the fuel tap but if I disconnect the pipes no fuel leeks out so the diaphram must be working.
Any ideas guys.

Re: Flooding
Posted: Thu Nov 11, 2010 9:25 am
by superlite
I think your image is too big to post - but they do look like clean carbs

That's a big bonus!
Sounds like you've got the float heights sorted (assuming they move freely). You say the carbs have been ultra-sonically cleaned, so you shouldn't have any problems with gunk. But have you checked that the float needles and the passages beneath them are free of fuel varnish? That's what I'd be checking first - have a good poke around in that area and check carefully I reckon.
Re: Flooding
Posted: Thu Nov 11, 2010 10:29 am
by TROUBLED OTTER
superlite wrote:I think your image is too big to post - but they do look like clean carbs

That's a big bonus!
Sounds like you've got the float heights sorted (assuming they move freely). You say the carbs have been ultra-sonically cleaned, so you shouldn't have any problems with gunk. But have you checked that the float needles and the passages beneath them are free of fuel varnish? That's what I'd be checking first - have a good poke around in that area and check carefully I reckon.
Yes I checked them and they are spottless.Its a strange one this.I spent 3 hours last night getting the floats spot on and cleaning and checking everything.

Re: Flooding
Posted: Thu Nov 11, 2010 10:57 am
by hunter
are they still flooding.
Re: Flooding
Posted: Thu Nov 11, 2010 11:52 am
by TROUBLED OTTER
Yes, but I dont know if its just one,two,three or all of them.When I took the carbs off, the back left valve port on the head was full to the top with petrol.

Thats what made me check the oil.
Re: Flooding
Posted: Thu Nov 11, 2010 1:20 pm
by TROUBLED OTTER
Better pic for you.

Re: Flooding
Posted: Thu Nov 11, 2010 5:30 pm
by hunter
If you have set the floats then it has got to be float needles,get some new ones.