1969 LeMans Vacuum Hose Routing Question

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dheupel

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I bought a 1969 LeMans last year. None of the vacuum lines are attached, and the ports have been blocked off. It idles very poorly. Can someone please tell me how to hook up the lines? I've seen several links to diagrams of old Chilton's manuals, and they don't help. The photos are too small to make out any details.

Currently, the input in the front on the Manifold is attached to the air filter housing, but that's about it. If someone could tell me that "Port X" (from my photo) should be attached to " TVS port YY" (for example), that would be very helpful.

I've attached a photo of my original equipment carb (Rochester 2bbl, Auto Trans, no power brakes, 350ci). The photo includes an inset photo of the vacuum switch, with the labels:

TVS Port Identifiers:
DR - Distributor Retard
CA - Carb Advance
M1 - Manifold
CR - Carb Retard
DA - Distributor Advance

Thanks!
 
is there a reason why you want the emission controls to work? The easiest thing is you need vacuum to port C for the choke pulloff so just attach it to port B or D, whichever port provides vacuum at idle. You say port A is already connected to the air cleaner, that is the correct location. Is you distributor vacuum advance hooked up, if not attach it to either port B or D whichever port provides no vacuum at idle but does have vacuum as you increase the engine speed. None of this may be the cause of your poor idle. Have you checked if the points are burnt? Have you checked the dwell? Have you checked the initial timing? Have you attempted to adjust the idle mixture screws?
 
The points, plugs, wires, distributor cap were all changed recently. Dwell, gap, and timing are set at spec. I've tried the carb mixture screws at several levels, and they are now currently about 3.5 turns out each, which seems to give the highest idle.

My distributor advance is hooked up (I assume this is the bell-shaped device at the bottom of the distributor, excuse my ignorance).

So I will try hooking up C with (D or B). If this doesn't seem to help, my next step might be a carb rebuild. Thanks for your help.
 
In your photo where is the large 3/8" hose in the back of the carburetor going? Yes the bell shaped device is the vacuum advance. If you want to spring for more bucks the best manual is the factory version which might be available from www.amesperf.com , look at the GTO catalog.
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Connecting those 2 ports with a hose made a big difference. It idles smoothly now. The hose in the back routes to the power booster near the master cylinder (which must mean it has power brakes). Thanks for your help.
 
I thought that hose was for the power brakes but was puzzled why you said you didnt have them. Good to hear you solved your problem.
 
dheupel said:
Connecting those 2 ports with a hose made a big difference. It idles smoothly now. The hose in the back routes to the power booster near the master cylinder (which must mean it has power brakes). Thanks for your help.
Click to expand...

In my 69 Ports C and B are connected. Port A is connected but not sure where that goes (no to the Thermal Switch though). Did you connect DA to D then? Did you connect any of the other ports on the Thermal Switch - none on mine are connected to anything.
 
Other than for originalty, is there a reason why you want to hook up lines to the thermal switch?
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I found some similarly equipped 350ci 2bbl Pontiacs at a show a couple of weeks ago, and was able to finally get it hooked up correctly (how it would have originally been hooked up). My car runs great.


DR - Distributor Retard - this is plugged (not used)
CA - Carb Advance - goes to the bell-shaped vacuum advance that is below/near the distributor cap
M1 - Manifold - attaches to the curved metal vacuum line coming out of the carb. Can see part of it at 9:00 on the far left of my photo
CR - Carb Retard - this is plugged (not used)
DA - Distributor Advance - goes to line coming out of back of carb (I have marked as "port D" on my photo)
 
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