ok I got some questions

[dodjh]

I made a vaccum guage and Y I C S tool as mentioned in this forum.

Tool in-- gauge hooked up-- (for sychronizing)

1 valve open --10 psi: 2 open--8 psi.
I adjust 2 to get close to 1. Turn 2 valve off open 1--reads 9
adjust and by this method they are both become 8 1/2.

go to 4 reads 6, close 4 open 3 it reads 11. close 3 open up 4 adjust to 9. close 4 open 3 reads 8. close 3 open 4 adjust and
get 9, close 4 open 3 get 7 (both 3 and 4 =7)

Do I adjust 1 and 2 for 7 or what is close to 7 and go back to 4 and adjust it to get to what 1 and 2 are which happens to be what 3 is also?
dodjh

[TopCatGr58]

Dude, you're almost there!!!

The actual values don't really matter, just that you are getting them to the same levels.

Now, do 2 and 3, and because 1 and 4 will adjust with 2 and 3, so when you get them reading the same, whether it be 6,7,8, as long as they are the same, then 1 and 4 will also be the same!
Good Job!!!
T.C.

[skids]

Re: ok I got some questions

If you see the way the linkages are fixed, No 3 is your control. You adjust No. 4 to the same pressure as 3 and you adjust No. 2 to read the same pressure as No 3. No 1 is the farthest away from No. 3 and needs to be adjusted to read the same as No. 2.

ie,
4 to 3
2 to 3
1 to 2
Then check again to ensure none of the adjustments drifted as you were making adjustments.

[pggg]

This YICS thing is way over my head, but, is connecting 2's vacuum to 3's vacuum and connecting 1's vacuum to 4's vacuum not just another way to get 'YICS'?

[renegade_xs11g]

Clymers says...

3 to 4 then
1 to 2 then
2 to 3 .....

I'd double check after all are done

[Ken Talbot]

Originally posted by pggg
This YICS thing is way over my head, but, is connecting 2's vacuum to 3's vacuum and connecting 1's vacuum to 4's vacuum not just another way to get 'YICS'?

Not really, pggg The YICS gallery on an XJ effectively joins all four intake manifiolds together. Without using a YICS tool to plug the passages that connect the four manifolds, a vacuum reading from any one manifold is actually that manifold's plus a bit from each of the other three. You could have all four carbs completely out of sync, but still have apparently the same vacuum reading at each.

[pggg]

Ken, if I balance all 4 carbs individually on my non YICS XS motor, then connect all 4 intake manifolds together via rubber hoses(with 'T' connectors to still run the petcocks) then I'll be getting the YICS effect then? My 78E is actually setup that way now, and runs sweet, although I've got 1 & 4 seperate from 2 & 3, as each piston pair is rising/falling in unison anyway, and each cylinder is still being 'scavanged' by it's opposite.