The vaccuum hoses to the 2 and 3 way valves were removed by the mechanic who installed webers onto my 250c. I need a schematic or description of which hoses go where from the valves..
Thanks,

Patrick

Doe you still need this? I am travelling until Monday, but can send you one after that.

Why do you want to hook the valves back up? It is best just to run a single vaccuum line to the advance side of the distributor.

Chuck

I was told that without the valves the distributor was fighting itself, with the advance and retard (dual vaccuum dist.) going against one another. True or not? I'm just trying to make the car run better. Weber 32/36 carbs... Any help would be appreciated. Thanks. Patrick Originally posted by ctaylor738:
Doe you still need this? I am travelling until Monday, but can send you one after that.

Why do you want to hook the valves back up? It is best just to run a single vaccuum line to the advance side of the distributor.

Chuck[/QUOTE]

PC:

I have a 250C with Webers. My advice is also to use the single advance line. Front Weber to the ADVANCE side of the distributor. Disconnect the retard side. Since the Weber has true "s-port" vacuum you will not have any vacuum at idle. I reset my ignition timing to 10 degrees BEFORE TDC at an idle of 900RPM.

When I got my car the two/three way's were not working and it had the stock carbs so I never used the valving anyhow. I believe (this may not be correct but "logic" tends to make me think this) that the original configuration was an early attempt at emissions control. At idle, vacuum was applied to the retard side then when going off idle vacuum to the redard side was killed and started to apply to the advance side. I tend to think that when the A/C was on and/or engine temp got a little high the same situation happened. Net result would have been an increase in timing and hence an increase in idle speed.

My car runs fine with the added advance and only the vacuum line from the front Weber to the distributor advance. Try it - see how it works.

My .02

Dan

__________________
Dan Taylor/ Tulsa, OK MBCA
'84 300D/'90 Jaguar XJ6/XJ40

Thank-you so much, I will give it a try. Does it matter if the retard end of the distributor is plugged or left open?

Patrick

PC:

I left mine uncapped so that vacuum applied to the advance side of the diaphram did not have to work against a partial vacuum caused by moving the diaphram away from the discharge chamber. I don't really know if it makes any difference or not - works for me.

Dan

__________________
Dan Taylor/ Tulsa, OK MBCA
'84 300D/'90 Jaguar XJ6/XJ40

Dan's da man! He knows his Zeniths. Actually the retard and advance is controlled by the temperature of the coolant to improve emissions as the engine was warming up. I believe that it was retarded until the engine warmed up, thus the higher idle required when cold.

Chuck

BTW - if the car is running OK, do not attempt to adjust the carbs.