Petcock Vacuum line, where too

[smurf]

So while removing my fuel tank I noticed on the petcock that there is a vacuum line, how over I dont see where to connect it too. the carbs I tied together with a vacuum line behind each carb, can I Tee into there?

Thanks for any help with my newb questionn

 

[16VGTIDave]

Yes, you can install a T-fitting into the vacuum line that you have installed, then connect to the petcock. I'd suggest centering the T-fitting between the vacuum fittings so you don't throw off the carb balance.

The stock setup is to cap the vacuum fitting furthest from the petcock, and connect the petcock to the closer.

 

[smurf]

Awesome that is what I thought I should do but didn't want to break anything.

 

[ChrisValentine]

So it there supposed to be a T into both those vacuum lines? Or does it just go to one and the other gets capped off.

I swear I just read that it only goes to one of them, now I'm confused.

 

[smurf]

from factory it goes to the closest carb, the furthest is capped.

i teed into the line in the middle and connect the petcock vacuum line. either or will work, I assume you will get better results from tee'ing into it IMO

 

[xschris]

The left gets capped and the line goes to the right one. Stock setup for the sohc xs400.

 

[jaeg]

The left gets capped and the line goes to the right one. Stock setup for the sohc xs400.

Thank you for pointing this out! I had set it up incorrectly when I’d rebuilt my carbs based on photos I’d seen. The motorcycle wasn’t running well prior to the rebuild and I had thought that was maybe one of the reasons why. I’m so glad you made mention of this!

Do you think this (vacuum line connected to left carb) would lead to what seems to be lack of fuel in the right cylinder when the engine is hot? I got myself stranded yesterday and prior to the bike completely giving up I’d lost my right cylinder for a bit.

I since checked my plugs and they look near perfect. Far better than they have in quite some time so I feel my mix/jetting/carbs are fine.

 

[xschris]

The line being plugged into the other air barb wont cause a cylinder to run rich unless fuel is being pulled into it. My guess is tuning or some other thing has caused this. It really could be anything from bad rings to timing off or carb setup .........

 

[jaeg]

The line being plugged into the other air barb wont cause a cylinder to run rich unless fuel is being pulled into it. My guess is tuning or some other thing has caused this. It really could be anything from bad rings to timing off or carb setup .........

Oh okay then. I guess the saga continues!
Thanks