blowing in vent lines help it start??

[dark7068]

if I blow into the vent lines, the bike will start.. no tank or petcock, filling the bowls and line till its full,, blow in the lines then seems like it stops taking air, then it will run for a minute or so. once the air is gone it wont run.. what am I doin wrong

[Agemax]

have you plugged the vacuum port on the carbs? this will be open to atmosphere if the tank and petcock is removed

[dark7068]

yes I have. its the twin carbs so 2 carbs and 1 vac. line and its plugged.

[Agemax]

does it run ok with the tank on?

[dark7068]

I haven't tried that. I just got a petcock yesterday and will button up some wiring tomorrow and put the tank on and give it a shot. I did get it running a few times tonite.


very strange. I cleaned the carbs and put in all new O-rings in them, and the carb mounts, installed them, filled them up and it fired first crack and ran great, still not using a tank. then wouldnt the next day. took the carbs off about 10 times to check every thing. still wouldn't run.. decided to blow in the vents tonite and it fired right up. I will put the tank on and put some gas in it tomorrow and see if it runs.

[JEEPRUSTY]

You are blowing fuel into the intake orifice of the carbs when you do the blowing.
Basically you are drip feeding the engine.

[dark7068]

I understand that, but I don't understand why its not working like it did when I first rebuilt the carbs,

[Agemax]

check your float heights

[dark7068]

thanx,, the floats were low. still not running right but at least starts almost every time without blowing in the vent lines. I will button up the wiring and put the tank on and try again.

[dark7068]

I set the floats to 20.5mm (+ or _) at the top of the floats with the carbs inverted. I cant really make out the online manual to where the floats should be set from.. it is the halfway line on the float or top of float? the halfway line sure seems pretty high if it is.

[Agemax]

set the float height from the gasket surface of the float bowl (without the gasket) to the top of the float.
i think you are almost there, just check them correctly.
spec is 20.5mm +or- 0.5 so set them to 20mm and you should be good to go

[dark7068]

I did that,, I got them to 20.5ish. now to adjust the air screws and idle and good to go., thanx a lot

Rick