vacuum & fuel lines

[mraaaaaaaaaa]

Hi, trying again to post. I need routing for the vacxuum & fuel lines for a 1978 xs 11e, thanks, Andy B.

[TopCatGr58]

Hey Andy,

Glad to see you finally got thru the registration process!!

The vacuum lines are from the Intake manifolds #1 and #4 and one goes to each petcock on that side. Then, the fuel line from each petcock goes to a pair of carbs. The OTHER vacuum line that comes from the left engine case Vacuum Advance pot goes to the #2 carb BODY, small metal port on the actual carb, NOT the Intake BOOT!! Hope this helps!
T.C.

[DiverRay]

Andy,
TC is close, but I have one of those bikes.
The petcock vacuum for the right side is off #3 carb, left side is off #2 carb. #1&4 carb s have caps on the vacuum ports. These are ALL the ports ON THE MANIFOLD, and NOT the carb itself. On #2 CARB BODY, there is a small, about 1/8" pipe that the vacuum advance connects.
The fuel lines should be connected as follows.
Right side, fuel line goes to BOTTOM "T" on carbs 1&2, left side of bike.
Left side, fuel lines go to BOTTOM "T", on carbs 3&4, right side of bike.
Top "T" on both sides go to front of air box. This is the breather for the float chamber in the carbs.

[mraaaaaaaaaa]

vacuum & fuel lines

Thanks T.C.,

Info makes sense to Me, & will do.

Have some more nipples that are uncovered :

Above fuel line from petcocks,

On the airbox; three; 1 big 1 that I think goes to the back top of the engine. the other two on the box goes where, maybe to the carbs , above fuel line, or is this wrong ?

Oh, on the engine back where the big nipple is, there is a small round thingy with a nipple on it also, which, stumps Me, lol.
Maybe it goes to a tee, and the big hose, & it connect together before the big hose goes to the airbox ???

Sorta wish the book would cover this, lol !!

Anyway, I think this is it for awile, tomorrow, going to hookup the carb, put some premium unleaded in the tank, & see if it kickes over.

Gunna say a prayer to the scooter god tonight, LOL

Take care, & thanks in advance, LTR, Andy B.

[mraaaaaaaaaa]

Vacuum & fuel lines

Thank You Diverray,

Got it, & will do, Makes sense !!!

Now, about the nipples on the back of the engine, LOL!!



TY in advance, ltr, Andy B.

[TopCatGr58]

Thanks Ray for that Clarification. I'm more familiar with Specials! I didn't think it mattered which Carb Boot port the petcocks were on as long as they were on the boot ports, there are 4, for synching, guess the inner ones keep the looks cleaner??

The small vent on the engine is the vent for the Middle Gear case, you have checked it for proper oil haven't you?? It just has a hose connected to it, and vents to AIR up under the tank. The larger hose you found goes to the larger Engine vent just behind the starter on the right of the engine. The other small ports on the air box are for the upper T's on the carbs, those are just vents, not FUEL lines. CHeck to make sure the air box ports are open, not clogged, same for the hoses on the upper T's, try blowing into them to see if you can, not hard, just enough to ensure air is flowing in.

If you will go to the LINKs section from the MAIN FORUM PAGE, and scroll IIRC to the 2nd page, you'll find a thread that will allow you to D/L a PDF copy of an owner's manual, complete with photos. IT's of an 81H/SH, but the engine is essentially the same, the carbs are a little different, but it's an Owner's manual, not a service one, just covers routine maintainance, but will show you about the middle and final drive oil levels and type which is different than the engine oil! (Hypoid 80-90wt)
T.C.

[Cosmo]

Andy, this may or may not apply but be sure the vacuum advance hose is in good repair and not split as was mine. The bike would not start and almost drove me crazy. After routing the vent hoses properly the bike ran fine. I have put several hundred miles on it and it runs better every day...Cosmo